var mathcolor = "blue";        // change it to "" (to inherit) or another color
var mathfontsize = "1em";      // change to e.g. 1.2em for larger math
var mathfontfamily = "serif";  // change to "" to inherit (works in IE) 
                               // or another family (e.g. "arial")
var automathrecognize = false; // writing "amath" on page makes this true
var checkForMathML = true;     // check if browser can display MathML
var notifyIfNoMathML = true;   // display note at top if no MathML capability
var alertIfNoMathML = false;   // show alert box if no MathML capability
var translateOnLoad = true;    // set to false to do call translators from js 
var translateLaTeX = true;     // false to preserve $..$, $$..$$
var translateLaTeXformatting = true; // false to preserve \emph,\begin{},\end{}
var translateASCIIMath = true; // false to preserve `..`
var translateASCIIsvg = true;  // false to preserve agraph.., \begin{graph}..
var avoidinnerHTML = false;   // set true if assigning to innerHTML gives error
var displaystyle = true;      // puts limits above and below large operators
var showasciiformulaonhover = true; // helps students learn ASCIIMath
var decimalsign = ".";        // change to "," if you like, beware of `(1,2)`!
var AMdelimiter1 = "`", AMescape1 = "\\\\`"; // can use other characters
var AMdocumentId = "wikitext" // PmWiki element containing math (default=body)
var checkforprocessasciimathinmoodle = false; // true for systems like Moodle
var dsvglocation = ""; // path to d.svg (blank if same as ASCIIMathML.js loc)

var isIE = document.createElementNS==null;

if (document.getElementById==null) 
  alert("This webpage requires a recent browser such as\
\nMozilla/Netscape 7+ or Internet Explorer 6+MathPlayer")

// all further ASCIIMathML global variables start with "AM"

function AMcreateElementXHTML(t) {
  if (isIE) return document.createElement(t);
  else return document.createElementNS("http://www.w3.org/1999/xhtml",t);
}

function AMnoMathMLNote() {
  var nd = AMcreateElementXHTML("");
  nd.setAttribute("","")
  nd.appendChild(AMcreateElementXHTML(""));
  nd.appendChild(document.createTextNode(""));
  var an = AMcreateElementXHTML("");
  an.appendChild(document.createTextNode(""));
  an.setAttribute("");
  nd.appendChild(an);
  nd.appendChild(document.createTextNode(""));  
  an = AMcreateElementXHTML("");
  an.appendChild(document.createTextNode(""));
  an.setAttribute("","");
  nd.appendChild(an);
  nd.appendChild(document.createTextNode(""));
  nd.appendChild(AMcreateElementXHTML(""));
  return nd;
}

function AMisMathMLavailable() {
  if (navigator.appName.slice(0,8)=="Netscape") 
    if (navigator.appVersion.slice(0,1)>="5") return null;
    else return AMnoMathMLNote();
  else if (navigator.appName.slice(0,9)=="Microsoft")
    try {
        var ActiveX = new ActiveXObject("MathPlayer.Factory.1");
        return null;
    } catch (e) {
        return AMnoMathMLNote();
    }
  else return AMnoMathMLNote();
}

// character lists for Mozilla/Netscape fonts
var AMcal = [0xEF35,0x212C,0xEF36,0xEF37,0x2130,0x2131,0xEF38,0x210B,0x2110,0xEF39,0xEF3A,0x2112,0x2133,0xEF3B,0xEF3C,0xEF3D,0xEF3E,0x211B,0xEF3F,0xEF40,0xEF41,0xEF42,0xEF43,0xEF44,0xEF45,0xEF46];
var AMfrk = [0xEF5D,0xEF5E,0x212D,0xEF5F,0xEF60,0xEF61,0xEF62,0x210C,0x2111,0xEF63,0xEF64,0xEF65,0xEF66,0xEF67,0xEF68,0xEF69,0xEF6A,0x211C,0xEF6B,0xEF6C,0xEF6D,0xEF6E,0xEF6F,0xEF70,0xEF71,0x2128];
var AMbbb = [0xEF8C,0xEF8D,0x2102,0xEF8E,0xEF8F,0xEF90,0xEF91,0x210D,0xEF92,0xEF93,0xEF94,0xEF95,0xEF96,0x2115,0xEF97,0x2119,0x211A,0x211D,0xEF98,0xEF99,0xEF9A,0xEF9B,0xEF9C,0xEF9D,0xEF9E,0x2124];

var CONST = 0, UNARY = 1, BINARY = 2, INFIX = 3, LEFTBRACKET = 4, 
    RIGHTBRACKET = 5, SPACE = 6, UNDEROVER = 7, DEFINITION = 8,
    LEFTRIGHT = 9, TEXT = 10; // token types

var AMsqrt = {input:"sqrt", tag:"msqrt", output:"sqrt", tex:null, ttype:UNARY},
  AMroot  = {input:"root", tag:"mroot", output:"root", tex:null, ttype:BINARY},
  AMfrac  = {input:"frac", tag:"mfrac", output:"/",    tex:null, ttype:BINARY},
  AMdiv   = {input:"/",    tag:"mfrac", output:"/",    tex:null, ttype:INFIX},
  AMover  = {input:"stackrel", tag:"mover", output:"stackrel", tex:null, ttype:BINARY},
  AMsub   = {input:"_",    tag:"msub",  output:"_",    tex:null, ttype:INFIX},
  AMsup   = {input:"^",    tag:"msup",  output:"^",    tex:null, ttype:INFIX},
  AMtext  = {input:"text", tag:"mtext", output:"text", tex:null, ttype:TEXT},
  AMmbox  = {input:"mbox", tag:"mtext", output:"mbox", tex:null, ttype:TEXT},
  AMquote = {input:"\"",   tag:"mtext", output:"mbox", tex:null, ttype:TEXT};

var AMsymbols = [
//some greek symbols
{input:"alpha",  tag:"mi", output:"\u03B1", tex:null, ttype:CONST},
{input:"beta",   tag:"mi", output:"\u03B2", tex:null, ttype:CONST},
{input:"chi",    tag:"mi", output:"\u03C7", tex:null, ttype:CONST},
{input:"delta",  tag:"mi", output:"\u03B4", tex:null, ttype:CONST},
{input:"Delta",  tag:"mo", output:"\u0394", tex:null, ttype:CONST},
{input:"epsi",   tag:"mi", output:"\u03B5", tex:"epsilon", ttype:CONST},
{input:"varepsilon", tag:"mi", output:"\u025B", tex:null, ttype:CONST},
{input:"eta",    tag:"mi", output:"\u03B7", tex:null, ttype:CONST},
{input:"gamma",  tag:"mi", output:"\u03B3", tex:null, ttype:CONST},
{input:"Gamma",  tag:"mo", output:"\u0393", tex:null, ttype:CONST},
{input:"iota",   tag:"mi", output:"\u03B9", tex:null, ttype:CONST},
{input:"kappa",  tag:"mi", output:"\u03BA", tex:null, ttype:CONST},
{input:"lambda", tag:"mi", output:"\u03BB", tex:null, ttype:CONST},
{input:"Lambda", tag:"mo", output:"\u039B", tex:null, ttype:CONST},
{input:"mu",     tag:"mi", output:"\u03BC", tex:null, ttype:CONST},
{input:"nu",     tag:"mi", output:"\u03BD", tex:null, ttype:CONST},
{input:"omega",  tag:"mi", output:"\u03C9", tex:null, ttype:CONST},
{input:"Omega",  tag:"mo", output:"\u03A9", tex:null, ttype:CONST},
{input:"phi",    tag:"mi", output:"\u03C6", tex:null, ttype:CONST},
{input:"varphi", tag:"mi", output:"\u03D5", tex:null, ttype:CONST},
{input:"Phi",    tag:"mo", output:"\u03A6", tex:null, ttype:CONST},
{input:"pi",     tag:"mi", output:"\u03C0", tex:null, ttype:CONST},
{input:"Pi",     tag:"mo", output:"\u03A0", tex:null, ttype:CONST},
{input:"psi",    tag:"mi", output:"\u03C8", tex:null, ttype:CONST},
{input:"Psi",    tag:"mi", output:"\u03A8", tex:null, ttype:CONST},
{input:"rho",    tag:"mi", output:"\u03C1", tex:null, ttype:CONST},
{input:"sigma",  tag:"mi", output:"\u03C3", tex:null, ttype:CONST},
{input:"Sigma",  tag:"mo", output:"\u03A3", tex:null, ttype:CONST},
{input:"tau",    tag:"mi", output:"\u03C4", tex:null, ttype:CONST},
{input:"theta",  tag:"mi", output:"\u03B8", tex:null, ttype:CONST},
{input:"vartheta", tag:"mi", output:"\u03D1", tex:null, ttype:CONST},
{input:"Theta",  tag:"mo", output:"\u0398", tex:null, ttype:CONST},
{input:"upsilon", tag:"mi", output:"\u03C5", tex:null, ttype:CONST},
{input:"xi",     tag:"mi", output:"\u03BE", tex:null, ttype:CONST},
{input:"Xi",     tag:"mo", output:"\u039E", tex:null, ttype:CONST},
{input:"zeta",   tag:"mi", output:"\u03B6", tex:null, ttype:CONST},

//binary operation symbols
//{input:"-",  tag:"mo", output:"\u0096", tex:null, ttype:CONST},
{input:"*",  tag:"mo", output:"\u22C5", tex:"cdot", ttype:CONST},
{input:"**", tag:"mo", output:"\u22C6", tex:"star", ttype:CONST},
{input:"//", tag:"mo", output:"/",      tex:null, ttype:CONST},
{input:"\\\\", tag:"mo", output:"\\",   tex:"backslash", ttype:CONST},
{input:"setminus", tag:"mo", output:"\\", tex:null, ttype:CONST},
{input:"xx", tag:"mo", output:"\u00D7", tex:"times", ttype:CONST},
{input:"-:", tag:"mo", output:"\u00F7", tex:"divide", ttype:CONST},
{input:"@",  tag:"mo", output:"\u2218", tex:"circ", ttype:CONST},
{input:"o+", tag:"mo", output:"\u2295", tex:"oplus", ttype:CONST},
{input:"ox", tag:"mo", output:"\u2297", tex:"otimes", ttype:CONST},
{input:"o.", tag:"mo", output:"\u2299", tex:"odot", ttype:CONST},
{input:"sum", tag:"mo", output:"\u2211", tex:null, ttype:UNDEROVER},
{input:"prod", tag:"mo", output:"\u220F", tex:null, ttype:UNDEROVER},
{input:"^^",  tag:"mo", output:"\u2227", tex:"wedge", ttype:CONST},
{input:"^^^", tag:"mo", output:"\u22C0", tex:"bigwedge", ttype:UNDEROVER},
{input:"vv",  tag:"mo", output:"\u2228", tex:"vee", ttype:CONST},
{input:"vvv", tag:"mo", output:"\u22C1", tex:"bigvee", ttype:UNDEROVER},
{input:"nn",  tag:"mo", output:"\u2229", tex:"cap", ttype:CONST},
{input:"nnn", tag:"mo", output:"\u22C2", tex:"bigcap", ttype:UNDEROVER},
{input:"uu",  tag:"mo", output:"\u222A", tex:"cup", ttype:CONST},
{input:"uuu", tag:"mo", output:"\u22C3", tex:"bigcup", ttype:UNDEROVER},

//binary relation symbols
{input:"!=",  tag:"mo", output:"\u2260", tex:"ne", ttype:CONST},
{input:":=",  tag:"mo", output:":=",     tex:null, ttype:CONST},
{input:"lt",  tag:"mo", output:"<",      tex:null, ttype:CONST},
{input:"<=",  tag:"mo", output:"\u2264", tex:"le", ttype:CONST},
{input:"lt=", tag:"mo", output:"\u2264", tex:"leq", ttype:CONST},
{input:">=",  tag:"mo", output:"\u2265", tex:"ge", ttype:CONST},
{input:"geq", tag:"mo", output:"\u2265", tex:null, ttype:CONST},
{input:"-<",  tag:"mo", output:"\u227A", tex:"prec", ttype:CONST},
{input:"-lt", tag:"mo", output:"\u227A", tex:null, ttype:CONST},
{input:">-",  tag:"mo", output:"\u227B", tex:"succ", ttype:CONST},
{input:"-<=", tag:"mo", output:"\u2AAF", tex:"preceq", ttype:CONST},
{input:">-=", tag:"mo", output:"\u2AB0", tex:"succeq", ttype:CONST},
{input:"in",  tag:"mo", output:"\u2208", tex:null, ttype:CONST},
{input:"!in", tag:"mo", output:"\u2209", tex:"notin", ttype:CONST},
{input:"sub", tag:"mo", output:"\u2282", tex:"subset", ttype:CONST},
{input:"sup", tag:"mo", output:"\u2283", tex:"supset", ttype:CONST},
{input:"sube", tag:"mo", output:"\u2286", tex:"subseteq", ttype:CONST},
{input:"supe", tag:"mo", output:"\u2287", tex:"supseteq", ttype:CONST},
{input:"-=",  tag:"mo", output:"\u2261", tex:"equiv", ttype:CONST},
{input:"~=",  tag:"mo", output:"\u2245", tex:"cong", ttype:CONST},
{input:"~~",  tag:"mo", output:"\u2248", tex:"approx", ttype:CONST},
{input:"prop", tag:"mo", output:"\u221D", tex:"propto", ttype:CONST},

//logical symbols
{input:"and", tag:"mtext", output:"and", tex:null, ttype:SPACE},
{input:"or",  tag:"mtext", output:"or",  tex:null, ttype:SPACE},
{input:"not", tag:"mo", output:"\u00AC", tex:"neg", ttype:CONST},
{input:"=>",  tag:"mo", output:"\u21D2", tex:"implies", ttype:CONST},
{input:"if",  tag:"mo", output:"if",     tex:null, ttype:SPACE},
{input:"<=>", tag:"mo", output:"\u21D4", tex:"iff", ttype:CONST},
{input:"AA",  tag:"mo", output:"\u2200", tex:"forall", ttype:CONST},
{input:"EE",  tag:"mo", output:"\u2203", tex:"exists", ttype:CONST},
{input:"_|_", tag:"mo", output:"\u22A5", tex:"bot", ttype:CONST},
{input:"TT",  tag:"mo", output:"\u22A4", tex:"top", ttype:CONST},
{input:"|--",  tag:"mo", output:"\u22A2", tex:"vdash", ttype:CONST},
{input:"|==",  tag:"mo", output:"\u22A8", tex:"models", ttype:CONST},

//grouping brackets
{input:"(", tag:"mo", output:"(", tex:null, ttype:LEFTBRACKET},
{input:")", tag:"mo", output:")", tex:null, ttype:RIGHTBRACKET},
{input:"[", tag:"mo", output:"[", tex:null, ttype:LEFTBRACKET},
{input:"]", tag:"mo", output:"]", tex:null, ttype:RIGHTBRACKET},
{input:"{", tag:"mo", output:"{", tex:null, ttype:LEFTBRACKET},
{input:"}", tag:"mo", output:"}", tex:null, ttype:RIGHTBRACKET},
{input:"|", tag:"mo", output:"|", tex:null, ttype:LEFTRIGHT},
//{input:"||", tag:"mo", output:"||", tex:null, ttype:LEFTRIGHT},
{input:"(:", tag:"mo", output:"\u2329", tex:"langle", ttype:LEFTBRACKET},
{input:":)", tag:"mo", output:"\u232A", tex:"rangle", ttype:RIGHTBRACKET},
{input:"<<", tag:"mo", output:"\u2329", tex:null, ttype:LEFTBRACKET},
{input:">>", tag:"mo", output:"\u232A", tex:null, ttype:RIGHTBRACKET},
{input:"{:", tag:"mo", output:"{:", tex:null, ttype:LEFTBRACKET, invisible:true},
{input:":}", tag:"mo", output:":}", tex:null, ttype:RIGHTBRACKET, invisible:true},

//miscellaneous symbols
{input:"int",  tag:"mo", output:"\u222B", tex:null, ttype:CONST},
{input:"dx",   tag:"mi", output:"{:d x:}", tex:null, ttype:DEFINITION},
{input:"dy",   tag:"mi", output:"{:d y:}", tex:null, ttype:DEFINITION},
{input:"dz",   tag:"mi", output:"{:d z:}", tex:null, ttype:DEFINITION},
{input:"dt",   tag:"mi", output:"{:d t:}", tex:null, ttype:DEFINITION},
{input:"oint", tag:"mo", output:"\u222E", tex:null, ttype:CONST},
{input:"del",  tag:"mo", output:"\u2202", tex:"partial", ttype:CONST},
{input:"grad", tag:"mo", output:"\u2207", tex:"nabla", ttype:CONST},
{input:"+-",   tag:"mo", output:"\u00B1", tex:"pm", ttype:CONST},
{input:"O/",   tag:"mo", output:"\u2205", tex:"emptyset", ttype:CONST},
{input:"oo",   tag:"mo", output:"\u221E", tex:"infty", ttype:CONST},
{input:"aleph", tag:"mo", output:"\u2135", tex:null, ttype:CONST},
{input:"...",  tag:"mo", output:"...",    tex:"ldots", ttype:CONST},
{input:":.",  tag:"mo", output:"\u2234",  tex:"therefore", ttype:CONST},
{input:"/_",  tag:"mo", output:"\u2220",  tex:"angle", ttype:CONST},
{input:"\\ ",  tag:"mo", output:"\u00A0", tex:null, ttype:CONST},
{input:"quad", tag:"mo", output:"\u00A0\u00A0", tex:null, ttype:CONST},
{input:"qquad", tag:"mo", output:"\u00A0\u00A0\u00A0\u00A0", tex:null, ttype:CONST},
{input:"cdots", tag:"mo", output:"\u22EF", tex:null, ttype:CONST},
{input:"vdots", tag:"mo", output:"\u22EE", tex:null, ttype:CONST},
{input:"ddots", tag:"mo", output:"\u22F1", tex:null, ttype:CONST},
{input:"diamond", tag:"mo", output:"\u22C4", tex:null, ttype:CONST},
{input:"square", tag:"mo", output:"\u25A1", tex:null, ttype:CONST},
{input:"|__", tag:"mo", output:"\u230A",  tex:"lfloor", ttype:CONST},
{input:"__|", tag:"mo", output:"\u230B",  tex:"rfloor", ttype:CONST},
{input:"|~", tag:"mo", output:"\u2308",  tex:"lceiling", ttype:CONST},
{input:"~|", tag:"mo", output:"\u2309",  tex:"rceiling", ttype:CONST},
{input:"CC",  tag:"mo", output:"\u2102", tex:null, ttype:CONST},
{input:"NN",  tag:"mo", output:"\u2115", tex:null, ttype:CONST},
{input:"QQ",  tag:"mo", output:"\u211A", tex:null, ttype:CONST},
{input:"RR",  tag:"mo", output:"\u211D", tex:null, ttype:CONST},
{input:"ZZ",  tag:"mo", output:"\u2124", tex:null, ttype:CONST},
{input:"f",   tag:"mi", output:"f",      tex:null, ttype:UNARY, func:true},
{input:"g",   tag:"mi", output:"g",      tex:null, ttype:UNARY, func:true},

//standard functions
{input:"lim",  tag:"mo", output:"lim", tex:null, ttype:UNDEROVER},
{input:"Lim",  tag:"mo", output:"Lim", tex:null, ttype:UNDEROVER},
{input:"sin",  tag:"mo", output:"sin", tex:null, ttype:UNARY, func:true},
{input:"cos",  tag:"mo", output:"cos", tex:null, ttype:UNARY, func:true},
{input:"tan",  tag:"mo", output:"tan", tex:null, ttype:UNARY, func:true},
{input:"sinh", tag:"mo", output:"sinh", tex:null, ttype:UNARY, func:true},
{input:"cosh", tag:"mo", output:"cosh", tex:null, ttype:UNARY, func:true},
{input:"tanh", tag:"mo", output:"tanh", tex:null, ttype:UNARY, func:true},
{input:"cot",  tag:"mo", output:"cot", tex:null, ttype:UNARY, func:true},
{input:"sec",  tag:"mo", output:"sec", tex:null, ttype:UNARY, func:true},
{input:"csc",  tag:"mo", output:"csc", tex:null, ttype:UNARY, func:true},
{input:"log",  tag:"mo", output:"log", tex:null, ttype:UNARY, func:true},
{input:"ln",   tag:"mo", output:"ln",  tex:null, ttype:UNARY, func:true},
{input:"det",  tag:"mo", output:"det", tex:null, ttype:UNARY, func:true},
{input:"dim",  tag:"mo", output:"dim", tex:null, ttype:CONST},
{input:"mod",  tag:"mo", output:"mod", tex:null, ttype:CONST},
{input:"gcd",  tag:"mo", output:"gcd", tex:null, ttype:UNARY, func:true},
{input:"lcm",  tag:"mo", output:"lcm", tex:null, ttype:UNARY, func:true},
{input:"lub",  tag:"mo", output:"lub", tex:null, ttype:CONST},
{input:"glb",  tag:"mo", output:"glb", tex:null, ttype:CONST},
{input:"min",  tag:"mo", output:"min", tex:null, ttype:UNDEROVER},
{input:"max",  tag:"mo", output:"max", tex:null, ttype:UNDEROVER},

//arrows
{input:"uarr", tag:"mo", output:"\u2191", tex:"uparrow", ttype:CONST},
{input:"darr", tag:"mo", output:"\u2193", tex:"downarrow", ttype:CONST},
{input:"rarr", tag:"mo", output:"\u2192", tex:"rightarrow", ttype:CONST},
{input:"->",   tag:"mo", output:"\u2192", tex:"to", ttype:CONST},
{input:"|->",  tag:"mo", output:"\u21A6", tex:"mapsto", ttype:CONST},
{input:"larr", tag:"mo", output:"\u2190", tex:"leftarrow", ttype:CONST},
{input:"harr", tag:"mo", output:"\u2194", tex:"leftrightarrow", ttype:CONST},
{input:"rArr", tag:"mo", output:"\u21D2", tex:"Rightarrow", ttype:CONST},
{input:"lArr", tag:"mo", output:"\u21D0", tex:"Leftarrow", ttype:CONST},
{input:"hArr", tag:"mo", output:"\u21D4", tex:"Leftrightarrow", ttype:CONST},

//commands with argument
AMsqrt, AMroot, AMfrac, AMdiv, AMover, AMsub, AMsup,
{input:"hat", tag:"mover", output:"\u005E", tex:null, ttype:UNARY, acc:true},
{input:"bar", tag:"mover", output:"\u00AF", tex:"overline", ttype:UNARY, acc:true},
{input:"vec", tag:"mover", output:"\u2192", tex:null, ttype:UNARY, acc:true},
{input:"dot", tag:"mover", output:".",      tex:null, ttype:UNARY, acc:true},
{input:"ddot", tag:"mover", output:"..",    tex:null, ttype:UNARY, acc:true},
{input:"ul", tag:"munder", output:"\u0332", tex:"underline", ttype:UNARY, acc:true},
AMtext, AMmbox, AMquote,
{input:"bb", tag:"mstyle", atname:"fontweight", atval:"bold", output:"bb", tex:null, ttype:UNARY},
{input:"mathbf", tag:"mstyle", atname:"fontweight", atval:"bold", output:"mathbf", tex:null, ttype:UNARY},
{input:"sf", tag:"mstyle", atname:"fontfamily", atval:"sans-serif", output:"sf", tex:null, ttype:UNARY},
{input:"mathsf", tag:"mstyle", atname:"fontfamily", atval:"sans-serif", output:"mathsf", tex:null, ttype:UNARY},
{input:"bbb", tag:"mstyle", atname:"mathvariant", atval:"double-struck", output:"bbb", tex:null, ttype:UNARY, codes:AMbbb},
{input:"mathbb", tag:"mstyle", atname:"mathvariant", atval:"double-struck", output:"mathbb", tex:null, ttype:UNARY, codes:AMbbb},
{input:"cc",  tag:"mstyle", atname:"mathvariant", atval:"script", output:"cc", tex:null, ttype:UNARY, codes:AMcal},
{input:"mathcal", tag:"mstyle", atname:"mathvariant", atval:"script", output:"mathcal", tex:null, ttype:UNARY, codes:AMcal},
{input:"tt",  tag:"mstyle", atname:"fontfamily", atval:"monospace", output:"tt", tex:null, ttype:UNARY},
{input:"mathtt", tag:"mstyle", atname:"fontfamily", atval:"monospace", output:"mathtt", tex:null, ttype:UNARY},
{input:"fr",  tag:"mstyle", atname:"mathvariant", atval:"fraktur", output:"fr", tex:null, ttype:UNARY, codes:AMfrk},
{input:"mathfrak",  tag:"mstyle", atname:"mathvariant", atval:"fraktur", output:"mathfrak", tex:null, ttype:UNARY, codes:AMfrk}
];

function compareNames(s1,s2) {
  if (s1.input > s2.input) return 1
  else return -1;
}

var AMnames = []; //list of input symbols

function AMinitSymbols() {
  var texsymbols = [], i;
  for (i=0; i<AMsymbols.length; i++)
    if (AMsymbols[i].tex) 
      texsymbols[texsymbols.length] = {input:AMsymbols[i].tex, 
        tag:AMsymbols[i].tag, output:AMsymbols[i].output, ttype:AMsymbols[i].ttype};
  AMsymbols = AMsymbols.concat(texsymbols);
  AMsymbols.sort(compareNames);
  for (i=0; i<AMsymbols.length; i++) AMnames[i] = AMsymbols[i].input;
}

var AMmathml = "http://www.w3.org/1998/Math/MathML";

function AMcreateElementMathML(t) {
  if (isIE) return document.createElement("m:"+t);
  else return document.createElementNS(AMmathml,t);
}

function AMcreateMmlNode(t,frag) {
//  var node = AMcreateElementMathML(name);
  if (isIE) var node = document.createElement("m:"+t);
  else var node = document.createElementNS(AMmathml,t);
  node.appendChild(frag);
  return node;
}

function define(oldstr,newstr) {
  AMsymbols = AMsymbols.concat([{input:oldstr, tag:"mo", output:newstr, 
                                 tex:null, ttype:DEFINITION}]);
  AMsymbols.sort(compareNames);
  for (i=0; i<AMsymbols.length; i++) AMnames[i] = AMsymbols[i].input;
}

function AMremoveCharsAndBlanks(str,n) {
//remove n characters and any following blanks
  var st;
  if (str.charAt(n)=="\\" && str.charAt(n+1)!="\\" && str.charAt(n+1)!=" ") 
    st = str.slice(n+1);
  else st = str.slice(n);
  for (var i=0; i<st.length && st.charCodeAt(i)<=32; i=i+1);
  return st.slice(i);
}

function AMposition(arr, str, n) { 
// return position >=n where str appears or would be inserted
// assumes arr is sorted
  if (n==0) {
    var h,m;
    n = -1;
    h = arr.length;
    while (n+1<h) {
      m = (n+h) >> 1;
      if (arr[m]<str) n = m; else h = m;
    }
    return h;
  } else
    for (var i=n; i<arr.length && arr[i]<str; i++);
  return i; // i=arr.length || arr[i]>=str
}

function AMgetSymbol(str) {
//return maximal initial substring of str that appears in names
//return null if there is none
  var k = 0; //new pos
  var j = 0; //old pos
  var mk; //match pos
  var st;
  var tagst;
  var match = "";
  var more = true;
  for (var i=1; i<=str.length && more; i++) {
    st = str.slice(0,i); //initial substring of length i
    j = k;
    k = AMposition(AMnames, st, j);
    if (k<AMnames.length && str.slice(0,AMnames[k].length)==AMnames[k]){
      match = AMnames[k];
      mk = k;
      i = match.length;
    }
    more = k<AMnames.length && str.slice(0,AMnames[k].length)>=AMnames[k];
  }
  AMpreviousSymbol=AMcurrentSymbol;
  if (match!=""){
    AMcurrentSymbol=AMsymbols[mk].ttype;
    return AMsymbols[mk]; 
  }
// if str[0] is a digit or - return maxsubstring of digits.digits
  AMcurrentSymbol=CONST;
  k = 1;
  st = str.slice(0,1);
  var integ = true;
  while ("0"<=st && st<="9" && k<=str.length) {
    st = str.slice(k,k+1);
    k++;
  }
  if (st == decimalsign) {
    st = str.slice(k,k+1);
    if ("0"<=st && st<="9") {
      integ = false;
      k++;
      while ("0"<=st && st<="9" && k<=str.length) {
        st = str.slice(k,k+1);
        k++;
      }
    }
  }
  if ((integ && k>1) || k>2) {
    st = str.slice(0,k-1);
    tagst = "mn";
  } else {
    k = 2;
    st = str.slice(0,1); //take 1 character
    tagst = (("A">st || st>"Z") && ("a">st || st>"z")?"mo":"mi");
  }
  if (st=="-" && AMpreviousSymbol==INFIX) {
    AMcurrentSymbol = INFIX;  //trick "/" into recognizing "-" on second parse
    return {input:st, tag:tagst, output:st, ttype:UNARY, func:true};
  }
  return {input:st, tag:tagst, output:st, ttype:CONST};
}

function AMremoveBrackets(node) {
  var st;
  if (node.nodeName=="mrow") {
    st = node.firstChild.firstChild.nodeValue;
    if (st=="(" || st=="[" || st=="{") node.removeChild(node.firstChild);
  }
  if (node.nodeName=="mrow") {
    st = node.lastChild.firstChild.nodeValue;
    if (st==")" || st=="]" || st=="}") node.removeChild(node.lastChild);
  }
}

/*Parsing ASCII math expressions with the following grammar
v ::= [A-Za-z] | greek letters | numbers | other constant symbols
u ::= sqrt | text | bb | other unary symbols for font commands
b ::= frac | root | stackrel         binary symbols
l ::= ( | [ | { | (: | {:            left brackets
r ::= ) | ] | } | :) | :}            right brackets
S ::= v | lEr | uS | bSS             Simple expression
I ::= S_S | S^S | S_S^S | S          Intermediate expression
E ::= IE | I/I                       Expression
Each terminal symbol is translated into a corresponding mathml node.*/

var AMnestingDepth,AMpreviousSymbol,AMcurrentSymbol;

function AMparseSexpr(str) { //parses str and returns [node,tailstr]
  var symbol, node, result, i, st,// rightvert = false,
    newFrag = document.createDocumentFragment();
  str = AMremoveCharsAndBlanks(str,0);
  symbol = AMgetSymbol(str);             //either a token or a bracket or empty
  if (symbol == null || symbol.ttype == RIGHTBRACKET && AMnestingDepth > 0) {
    return [null,str];
  }
  if (symbol.ttype == DEFINITION) {
    str = symbol.output+AMremoveCharsAndBlanks(str,symbol.input.length); 
    symbol = AMgetSymbol(str);
  }
  switch (symbol.ttype) {
  case UNDEROVER:
  case CONST:
    str = AMremoveCharsAndBlanks(str,symbol.input.length); 
    return [AMcreateMmlNode(symbol.tag,        //its a constant
                             document.createTextNode(symbol.output)),str];
  case LEFTBRACKET:   //read (expr+)
    AMnestingDepth++;
    str = AMremoveCharsAndBlanks(str,symbol.input.length); 
    result = AMparseExpr(str,true);
    AMnestingDepth--;
    if (typeof symbol.invisible == "boolean" && symbol.invisible) 
      node = AMcreateMmlNode("mrow",result[0]);
    else {
      node = AMcreateMmlNode("mo",document.createTextNode(symbol.output));
      node = AMcreateMmlNode("mrow",node);
      node.appendChild(result[0]);
    }
    return [node,result[1]];
  case TEXT:
      if (symbol!=AMquote) str = AMremoveCharsAndBlanks(str,symbol.input.length);
      if (str.charAt(0)=="{") i=str.indexOf("}");
      else if (str.charAt(0)=="(") i=str.indexOf(")");
      else if (str.charAt(0)=="[") i=str.indexOf("]");
      else if (symbol==AMquote) i=str.slice(1).indexOf("\"")+1;
      else i = 0;
      if (i==-1) i = str.length;
      st = str.slice(1,i);
      if (st.charAt(0) == " ") {
        node = AMcreateElementMathML("mspace");
        node.setAttribute("width","1ex");
        newFrag.appendChild(node);
      }
      newFrag.appendChild(
        AMcreateMmlNode(symbol.tag,document.createTextNode(st)));
      if (st.charAt(st.length-1) == " ") {
        node = AMcreateElementMathML("mspace");
        node.setAttribute("width","1ex");
        newFrag.appendChild(node);
      }
      str = AMremoveCharsAndBlanks(str,i+1);
      return [AMcreateMmlNode("mrow",newFrag),str];
  case UNARY:
      str = AMremoveCharsAndBlanks(str,symbol.input.length); 
      result = AMparseSexpr(str);
      if (result[0]==null) return [AMcreateMmlNode(symbol.tag,
                             document.createTextNode(symbol.output)),str];
      if (typeof symbol.func == "boolean" && symbol.func) { // functions hack
        st = str.charAt(0);
        if (st=="^" || st=="_" || st=="/" || st=="|" || st==",") {
          return [AMcreateMmlNode(symbol.tag,
                    document.createTextNode(symbol.output)),str];
        } else {
          node = AMcreateMmlNode("mrow",
           AMcreateMmlNode(symbol.tag,document.createTextNode(symbol.output)));
          node.appendChild(result[0]);
          return [node,result[1]];
        }
      }
      AMremoveBrackets(result[0]);
      if (symbol.input == "sqrt") {           // sqrt
        return [AMcreateMmlNode(symbol.tag,result[0]),result[1]];
      } else if (typeof symbol.acc == "boolean" && symbol.acc) {   // accent
        node = AMcreateMmlNode(symbol.tag,result[0]);
        node.appendChild(AMcreateMmlNode("mo",document.createTextNode(symbol.output)));
        return [node,result[1]];
      } else {                        // font change command
        if (!isIE && typeof symbol.codes != "undefined") {
          for (i=0; i<result[0].childNodes.length; i++)
            if (result[0].childNodes[i].nodeName=="mi" || result[0].nodeName=="mi") {
              st = (result[0].nodeName=="mi"?result[0].firstChild.nodeValue:
                              result[0].childNodes[i].firstChild.nodeValue);
              var newst = [];
              for (var j=0; j<st.length; j++)
                if (st.charCodeAt(j)>64 && st.charCodeAt(j)<91) newst = newst +
                  String.fromCharCode(symbol.codes[st.charCodeAt(j)-65]);
                else newst = newst + st.charAt(j);
              if (result[0].nodeName=="mi")
                result[0]=AMcreateElementMathML("mo").
                          appendChild(document.createTextNode(newst));
              else result[0].replaceChild(AMcreateElementMathML("mo").
          appendChild(document.createTextNode(newst)),result[0].childNodes[i]);
            }
        }
        node = AMcreateMmlNode(symbol.tag,result[0]);
        node.setAttribute(symbol.atname,symbol.atval);
        return [node,result[1]];
      }
  case BINARY:
    str = AMremoveCharsAndBlanks(str,symbol.input.length); 
    result = AMparseSexpr(str);
    if (result[0]==null) return [AMcreateMmlNode("mo",
                           document.createTextNode(symbol.input)),str];
    AMremoveBrackets(result[0]);
    var result2 = AMparseSexpr(result[1]);
    if (result2[0]==null) return [AMcreateMmlNode("mo",
                           document.createTextNode(symbol.input)),str];
    AMremoveBrackets(result2[0]);
    if (symbol.input=="root" || symbol.input=="stackrel") 
      newFrag.appendChild(result2[0]);
    newFrag.appendChild(result[0]);
    if (symbol.input=="frac") newFrag.appendChild(result2[0]);
    return [AMcreateMmlNode(symbol.tag,newFrag),result2[1]];
  case INFIX:
    str = AMremoveCharsAndBlanks(str,symbol.input.length); 
    return [AMcreateMmlNode("mo",document.createTextNode(symbol.output)),str];
  case SPACE:
    str = AMremoveCharsAndBlanks(str,symbol.input.length); 
    node = AMcreateElementMathML("mspace");
    node.setAttribute("width","1ex");
    newFrag.appendChild(node);
    newFrag.appendChild(
      AMcreateMmlNode(symbol.tag,document.createTextNode(symbol.output)));
    node = AMcreateElementMathML("mspace");
    node.setAttribute("width","1ex");
    newFrag.appendChild(node);
    return [AMcreateMmlNode("mrow",newFrag),str];
  case LEFTRIGHT:
//    if (rightvert) return [null,str]; else rightvert = true;
    AMnestingDepth++;
    str = AMremoveCharsAndBlanks(str,symbol.input.length); 
    result = AMparseExpr(str,false);
    AMnestingDepth--;
    var st = "";
    if (result[0].lastChild!=null)
      st = result[0].lastChild.firstChild.nodeValue;
    if (st == "|") { // its an absolute value subterm
      node = AMcreateMmlNode("mo",document.createTextNode(symbol.output));
      node = AMcreateMmlNode("mrow",node);
      node.appendChild(result[0]);
      return [node,result[1]];
    } else { // the "|" is a \mid
      node = AMcreateMmlNode("mo",document.createTextNode(symbol.output));
      node = AMcreateMmlNode("mrow",node);
      return [node,str];
    }
  default:
//alert("default");
    str = AMremoveCharsAndBlanks(str,symbol.input.length); 
    return [AMcreateMmlNode(symbol.tag,        //its a constant
                             document.createTextNode(symbol.output)),str];
  }
}

function AMparseIexpr(str) {
  var symbol, sym1, sym2, node, result, underover;
  str = AMremoveCharsAndBlanks(str,0);
  sym1 = AMgetSymbol(str);
  result = AMparseSexpr(str);
  node = result[0];
  str = result[1];
  symbol = AMgetSymbol(str);
  if (symbol.ttype == INFIX && symbol.input != "/") {
    str = AMremoveCharsAndBlanks(str,symbol.input.length);
//    if (symbol.input == "/") result = AMparseIexpr(str); else ...
    result = AMparseSexpr(str);
    if (result[0] == null) // show box in place of missing argument
      result[0] = AMcreateMmlNode("mo",document.createTextNode("\u25A1"));
    else AMremoveBrackets(result[0]);
    str = result[1];
//    if (symbol.input == "/") AMremoveBrackets(node);
    if (symbol.input == "_") {
      sym2 = AMgetSymbol(str);
      underover = (sym1.ttype == UNDEROVER);
      if (sym2.input == "^") {
        str = AMremoveCharsAndBlanks(str,sym2.input.length);
        var res2 = AMparseSexpr(str);
        AMremoveBrackets(res2[0]);
        str = res2[1];
        node = AMcreateMmlNode((underover?"munderover":"msubsup"),node);
        node.appendChild(result[0]);
        node.appendChild(res2[0]);
        node = AMcreateMmlNode("mrow",node); // so sum does not stretch
      } else {
        node = AMcreateMmlNode((underover?"munder":"msub"),node);
        node.appendChild(result[0]);
      }
    } else {
      node = AMcreateMmlNode(symbol.tag,node);
      node.appendChild(result[0]);
    }
  }
  return [node,str];
}

function AMparseExpr(str,rightbracket) {
  var symbol, node, result, i, nodeList = [],
  newFrag = document.createDocumentFragment();
  do {
    str = AMremoveCharsAndBlanks(str,0);
    result = AMparseIexpr(str);
    node = result[0];
    str = result[1];
    symbol = AMgetSymbol(str);
    if (symbol.ttype == INFIX && symbol.input == "/") {
      str = AMremoveCharsAndBlanks(str,symbol.input.length);
      result = AMparseIexpr(str);
      if (result[0] == null) // show box in place of missing argument
        result[0] = AMcreateMmlNode("mo",document.createTextNode("\u25A1"));
      else AMremoveBrackets(result[0]);
      str = result[1];
      AMremoveBrackets(node);
      node = AMcreateMmlNode(symbol.tag,node);
      node.appendChild(result[0]);
      newFrag.appendChild(node);
      symbol = AMgetSymbol(str);
    } 
    else if (node!=undefined) newFrag.appendChild(node);
  } while ((symbol.ttype != RIGHTBRACKET && 
           (symbol.ttype != LEFTRIGHT || rightbracket)
           || AMnestingDepth == 0) && symbol!=null && symbol.output!="");
  if (symbol.ttype == RIGHTBRACKET || symbol.ttype == LEFTRIGHT) {
//    if (AMnestingDepth > 0) AMnestingDepth--;
    var len = newFrag.childNodes.length;
    if (len>0 && newFrag.childNodes[len-1].nodeName == "mrow" && len>1 &&
      newFrag.childNodes[len-2].nodeName == "mo" &&
      newFrag.childNodes[len-2].firstChild.nodeValue == ",") { //matrix
      var right = newFrag.childNodes[len-1].lastChild.firstChild.nodeValue;
      if (right==")" || right=="]") {
        var left = newFrag.childNodes[len-1].firstChild.firstChild.nodeValue;
        if (left=="(" && right==")" && symbol.output != "}" || 
            left=="[" && right=="]") {
        var pos = []; // positions of commas
        var matrix = true;
        var m = newFrag.childNodes.length;
        for (i=0; matrix && i<m; i=i+2) {
          pos[i] = [];
          node = newFrag.childNodes[i];
          if (matrix) matrix = node.nodeName=="mrow" && 
            (i==m-1 || node.nextSibling.nodeName=="mo" && 
            node.nextSibling.firstChild.nodeValue==",")&&
            node.firstChild.firstChild.nodeValue==left &&
            node.lastChild.firstChild.nodeValue==right;
          if (matrix) 
            for (var j=0; j<node.childNodes.length; j++)
              if (node.childNodes[j].firstChild.nodeValue==",")
                pos[i][pos[i].length]=j;
          if (matrix && i>1) matrix = pos[i].length == pos[i-2].length;
        }
        if (matrix) {
          var row, frag, n, k, table = document.createDocumentFragment();
          for (i=0; i<m; i=i+2) {
            row = document.createDocumentFragment();
            frag = document.createDocumentFragment();
            node = newFrag.firstChild; // <mrow>(-,-,...,-,-)</mrow>
            n = node.childNodes.length;
            k = 0;
            node.removeChild(node.firstChild); //remove (
            for (j=1; j<n-1; j++) {
              if (typeof pos[i][k] != "undefined" && j==pos[i][k]){
                node.removeChild(node.firstChild); //remove ,
                row.appendChild(AMcreateMmlNode("mtd",frag));
                k++;
              } else frag.appendChild(node.firstChild);
            }
            row.appendChild(AMcreateMmlNode("mtd",frag));
            if (newFrag.childNodes.length>2) {
              newFrag.removeChild(newFrag.firstChild); //remove <mrow>)</mrow>
              newFrag.removeChild(newFrag.firstChild); //remove <mo>,</mo>
            }
            table.appendChild(AMcreateMmlNode("mtr",row));
          }
          node = AMcreateMmlNode("mtable",table);
          if (typeof symbol.invisible == "boolean" && symbol.invisible) node.setAttribute("columnalign","left");
          newFrag.replaceChild(node,newFrag.firstChild);
        }
       }
      }
    }
    str = AMremoveCharsAndBlanks(str,symbol.input.length);
    if (typeof symbol.invisible != "boolean" || !symbol.invisible) {
      node = AMcreateMmlNode("mo",document.createTextNode(symbol.output));
      newFrag.appendChild(node);
    }
  }
  return [newFrag,str];
}

function AMparseMath(str) {
  var result, node = AMcreateElementMathML("mstyle");
  if (mathcolor != "") node.setAttribute("mathcolor",mathcolor);
  if (displaystyle) node.setAttribute("displaystyle","true");
  if (mathfontfamily != "") node.setAttribute("fontfamily",mathfontfamily);
  AMnestingDepth = 0;
  node.appendChild(AMparseExpr(str.replace(/^\s+/g,""),false)[0]);
  node = AMcreateMmlNode("math",node);
  if (showasciiformulaonhover)                      //fixed by djhsu so newline
    node.setAttribute("title",str.replace(/\s+/g," "));//does not show in Gecko
  var fnode = AMcreateElementXHTML("span");
  fnode.style.fontSize = mathfontsize;
  if (mathfontfamily != "") fnode.style.fontFamily = mathfontfamily;
  fnode.appendChild(node);
  return fnode;
}

function AMstrarr2docFrag(arr, linebreaks) {
  var newFrag=document.createDocumentFragment();
  var expr = false;
  for (var i=0; i<arr.length; i++) {
    if (expr) newFrag.appendChild(AMparseMath(arr[i]));
    else {
      var arri = (linebreaks ? arr[i].split("\n\n") : [arr[i]]);
      newFrag.appendChild(AMcreateElementXHTML("span").
      appendChild(document.createTextNode(arri[0])));
      for (var j=1; j<arri.length; j++) {
        newFrag.appendChild(AMcreateElementXHTML("p"));
        newFrag.appendChild(AMcreateElementXHTML("span").
        appendChild(document.createTextNode(arri[j])));
      }
    }
    expr = !expr;
  }
  return newFrag;
}

function AMautomathrec(str) {
//formula is a space (or start of str) followed by a maximal sequence of *two* or more tokens, possibly separated by runs of digits and/or space.
//tokens are single letters (except a, A, I) and ASCIIMathML tokens
  var texcommand = "\\\\[a-zA-Z]+|\\\\\\s|";
  var ambigAMtoken = "\\b(?:oo|lim|ln|int|oint|del|grad|aleph|prod|prop|sinh|cosh|tanh|cos|sec|pi|tt|fr|sf|sube|supe|sub|sup|det|mod|gcd|lcm|min|max|vec|ddot|ul|chi|eta|nu|mu)(?![a-z])|";
  var englishAMtoken = "\\b(?:sum|ox|log|sin|tan|dim|hat|bar|dot)(?![a-z])|";
  var secondenglishAMtoken = "|\\bI\\b|\\bin\\b|\\btext\\b"; // took if and or not out
  var simpleAMtoken = "NN|ZZ|QQ|RR|CC|TT|AA|EE|sqrt|dx|dy|dz|dt|xx|vv|uu|nn|bb|cc|csc|cot|alpha|beta|delta|Delta|epsilon|gamma|Gamma|kappa|lambda|Lambda|omega|phi|Phi|Pi|psi|Psi|rho|sigma|Sigma|tau|theta|Theta|xi|Xi|zeta"; // uuu nnn?
  var letter = "[a-zA-HJ-Z](?=(?:[^a-zA-Z]|$|"+ambigAMtoken+englishAMtoken+simpleAMtoken+"))|";
  var token = letter+texcommand+"\\d+|[-()[\\]{}+=*&^_%@/<>,\\|!:;'~]|\\.(?!(?:\x20|$))|"+ambigAMtoken+englishAMtoken+simpleAMtoken;
  var re = new RegExp("(^|\\s)((("+token+")\\s?)(("+token+secondenglishAMtoken+")\\s?)+)([,.?]?(?=\\s|$))","g");
  str = str.replace(re," `$2`$7");
  var arr = str.split(AMdelimiter1);
  var re1 = new RegExp("(^|\\s)([b-zB-HJ-Z+*<>]|"+texcommand+ambigAMtoken+simpleAMtoken+")(\\s|\\n|$)","g");
  var re2 = new RegExp("(^|\\s)([a-z]|"+texcommand+ambigAMtoken+simpleAMtoken+")([,.])","g"); // removed |\d+ for now
  for (i=0; i<arr.length; i++)   //single nonenglish tokens
    if (i%2==0) {
      arr[i] = arr[i].replace(re1," `$2`$3");
      arr[i] = arr[i].replace(re2," `$2`$3");
      arr[i] = arr[i].replace(/([{}[\]])/,"`$1`");
    }
  str = arr.join(AMdelimiter1);
  str = str.replace(/(\([a-zA-Z]{2,}.*?)\)`/g,"$1`)");  //fix parentheses
  str = str.replace(/`(\((a\s|in\s))(.*?[a-zA-Z]{2,}\))/g,"$1`$3");  //fix parentheses
  str = str.replace(/\sin`/g,"` in");
  str = str.replace(/`(\(\w\)[,.]?(\s|\n|$))/g,"$1`");
  str = str.replace(/`([0-9.]+|e.g)`(\\.)/gi,"$1$2");
  str = str.replace(/`([0-9.]:)`/g,"$1");
  return str;
}

function AMprocessNodeR(n, linebreaks) {
  var mtch, str, arr, frg, i;
  if (n.childNodes.length == 0) {
   if ((n.nodeType!=8 || linebreaks) &&
    n.parentNode.nodeName!="form" && n.parentNode.nodeName!="FORM" &&
    n.parentNode.nodeName!="textarea" && n.parentNode.nodeName!="TEXTAREA" &&
    n.parentNode.nodeName!="pre" && n.parentNode.nodeName!="PRE") {
    str = n.nodeValue;
    if (!(str == null)) {
      str = str.replace(/\r\n\r\n/g,"\n\n");
      str = str.replace(/\x20+/g," ");
      str = str.replace(/\s*\r\n/g," ");
      mtch = false;
      str = str.replace(new RegExp(AMescape1, "g"),
              function(){mtch = true; return "AMescape1"});
      str = str.replace(/\\?end{?a?math}?/i,
              function(){automathrecognize = false; mtch = true; return ""});
      str = str.replace(/amath|\\begin{a?math}/i,
              function(){automathrecognize = true; mtch = true; return ""});
      arr = str.split(AMdelimiter1);
      if (automathrecognize)
        for (i=0; i<arr.length; i++)
          if (i%2==0) arr[i] = AMautomathrec(arr[i]);
      str = arr.join(AMdelimiter1);
      arr = str.split(AMdelimiter1);
      for (i=0; i<arr.length; i++) // this is a problem ************
        arr[i]=arr[i].replace(/AMescape1/g,AMdelimiter1);
      if (arr.length>1 || mtch) {
        if (checkForMathML) {
          checkForMathML = false;
          var nd = AMisMathMLavailable();
          AMnoMathML = nd != null;
          if (AMnoMathML && notifyIfNoMathML) 
            if (alertIfNoMathML)
              alert("To view the ASCIIMathML notation use Internet Explorer 6 +\nMathPlayer (free from www.dessci.com)\n\
                or Firefox/Mozilla/Netscape");
            //else AMbody.insertBefore(nd,AMbody.childNodes[0]);
        }
        if (!AMnoMathML) {
          frg = AMstrarr2docFrag(arr,n.nodeType==8);
          var len = frg.childNodes.length;
          n.parentNode.replaceChild(frg,n);
          return len-1;
        } else return 0;
      }
    }
   } else return 0;
  } else if (n.nodeName!="math") {
    for (i=0; i<n.childNodes.length; i++)
      i += AMprocessNodeR(n.childNodes[i], linebreaks);
  }
  return 0;
}

function AMprocessNode(n, linebreaks, spanclassAM) {
  var frag,st;
  if (spanclassAM!=null) {
    frag = document.getElementsByTagName("span")
    for (var i=0;i<frag.length;i++)
      if (frag[i].className == "AM")
        AMprocessNodeR(frag[i],linebreaks);
  } else {
    try {
      st = n.innerHTML; // look for AMdelimiter on page
    } catch(err) {}
    if (st==null || /amath|\\begin{a?math}/i.test(st) ||
      st.indexOf(AMdelimiter1+" ")!=-1 || st.slice(-1)==AMdelimiter1 ||
      st.indexOf(AMdelimiter1+"<")!=-1 || st.indexOf(AMdelimiter1+"\n")!=-1) {
      AMprocessNodeR(n,linebreaks);
    }
  }
  if (isIE) { //needed to match size and font of formula to surrounding text
    frag = document.getElementsByTagName('math');
    for (var i=0;i<frag.length;i++) frag[i].update()
  }
}

var AMbody;
var AMnoMathML = false, AMtranslated = false;

function translate(spanclassAM) {
  if (!AMtranslated) { // run this only once
    AMtranslated = true;
    AMbody = document.getElementsByTagName("body")[0];
    var processN = document.getElementById(AMdocumentId);
//    var processN = getElementsByClass(AMbody,"div",AMdocumentClass);
    AMprocessNode((processN!=null?processN:AMbody), false, spanclassAM);
  }
}

AMinitSymbols();


var LMcheckForMathML = true;   // check if browser can display MathML
var LMnotifyIfNoMathML = true; // display note if no MathML capability
var LMalertIfNoMathML = false;  // show alert box if no MathML capability
var LMmathcolor = "";	     // "" (to inherit) or change to another color
var LMmathfontfamily = "serif"; // change to "" to inherit (works in IE)
                                // or another family (e.g. "arial")
var LMshowasciiformulaonhover = true; // helps students learn LaTeX

// all further global variables start with "LM"

function LMcreateElementXHTML(t) {
  if (isIE) return document.createElement(t);
  else return document.createElementNS("http://www.w3.org/1999/xhtml",t);
}

function LMnoMathMLNote() {
  var nd = LMcreateElementXHTML("");
  nd.setAttribute("","")
  nd.appendChild(LMcreateElementXHTML(""));
  nd.appendChild(document.createTextNode(""));
  var an = LMcreateElementXHTML("");
  an.appendChild(document.createTextNode(""));
  an.setAttribute("","");
  nd.appendChild(an);
  nd.appendChild(document.createTextNode("")); 
  an = LMcreateElementXHTML("");
  an.appendChild(document.createTextNode(""));
  an.setAttribute("","");
  nd.appendChild(an);
  nd.appendChild(document.createTextNode(""));
  nd.appendChild(LMcreateElementXHTML(""));
  return nd;
}

function LMisMathMLavailable() {
  if (navigator.appName.slice(0,8)=="Netscape")
    if (navigator.appVersion.slice(0,1)>="5") return null;
    else return LMnoMathMLNote();
  else if (navigator.appName.slice(0,9)=="Microsoft")
    try {
        var ActiveX = new ActiveXObject("MathPlayer.Factory.1");
        return null;
    } catch (e) {
        return LMnoMathMLNote();
    }
  else return LMnoMathMLNote();
}

// character lists for Mozilla/Netscape fonts
var LMcal = [0xEF35,0x212C,0xEF36,0xEF37,0x2130,0x2131,0xEF38,0x210B,0x2110,0xEF39,0xEF3A,0x2112,0x2133,0xEF3B,0xEF3C,0xEF3D,0xEF3E,0x211B,0xEF3F,0xEF40,0xEF41,0xEF42,0xEF43,0xEF44,0xEF45,0xEF46];
var LMfrk = [0xEF5D,0xEF5E,0x212D,0xEF5F,0xEF60,0xEF61,0xEF62,0x210C,0x2111,0xEF63,0xEF64,0xEF65,0xEF66,0xEF67,0xEF68,0xEF69,0xEF6A,0x211C,0xEF6B,0xEF6C,0xEF6D,0xEF6E,0xEF6F,0xEF70,0xEF71,0x2128];
var LMbbb = [0xEF8C,0xEF8D,0x2102,0xEF8E,0xEF8F,0xEF90,0xEF91,0x210D,0xEF92,0xEF93,0xEF94,0xEF95,0xEF96,0x2115,0xEF97,0x2119,0x211A,0x211D,0xEF98,0xEF99,0xEF9A,0xEF9B,0xEF9C,0xEF9D,0xEF9E,0x2124];

//var CONST = 0, UNARY = 1, BINARY = 2, INFIX = 3, LEFTBRACKET = 4,
//    RIGHTBRACKET = 5, SPACE = 6, UNDEROVER = 7, DEFINITION = 8, TEXT = 10, 
var BIG = 11, LONG = 12, STRETCHY = 13, MATRIX = 14; // token types

var LMsqrt = {input:"\\sqrt",	tag:"msqrt", output:"sqrt",	ttype:UNARY},
  LMroot = {input:"\\root",	tag:"mroot", output:"root",	ttype:BINARY},
  LMfrac = {input:"\\frac",	tag:"mfrac", output:"/",	ttype:BINARY},
  LMover = {input:"\\stackrel", tag:"mover", output:"stackrel", ttype:BINARY},
  LMatop = {input:"\\atop",	tag:"mfrac", output:"",		ttype:INFIX},
  LMchoose = {input:"\\choose", tag:"mfrac", output:"",		ttype:INFIX},
  LMsub  = {input:"_",		tag:"msub",  output:"_",	ttype:INFIX},
  LMsup  = {input:"^",		tag:"msup",  output:"^",	ttype:INFIX},
  LMtext = {input:"\\mathrm",	tag:"mtext", output:"text",	ttype:TEXT},
  LMmbox = {input:"\\mbox",	tag:"mtext", output:"mbox",	ttype:TEXT};

// Commented out by DRW to prevent 1/2 turning into a 2-line fraction
// LMdiv   = {input:"/",	 tag:"mfrac", output:"/",    ttype:INFIX},
// Commented out by DRW so that " prints literally in equations
// LMquote = {input:"\"",	 tag:"mtext", output:"mbox", ttype:TEXT};

var LMsymbols = [
//Greek letters
{input:"\\alpha",	tag:"mi", output:"\u03B1", ttype:CONST},
{input:"\\beta",	tag:"mi", output:"\u03B2", ttype:CONST},
{input:"\\gamma",	tag:"mi", output:"\u03B3", ttype:CONST},
{input:"\\delta",	tag:"mi", output:"\u03B4", ttype:CONST},
{input:"\\epsilon",	tag:"mi", output:"\u03B5", ttype:CONST},
{input:"\\varepsilon",  tag:"mi", output:"\u025B", ttype:CONST},
{input:"\\zeta",	tag:"mi", output:"\u03B6", ttype:CONST},
{input:"\\eta",		tag:"mi", output:"\u03B7", ttype:CONST},
{input:"\\theta",	tag:"mi", output:"\u03B8", ttype:CONST},
{input:"\\vartheta",	tag:"mi", output:"\u03D1", ttype:CONST},
{input:"\\iota",	tag:"mi", output:"\u03B9", ttype:CONST},
{input:"\\kappa",	tag:"mi", output:"\u03BA", ttype:CONST},
{input:"\\lambda",	tag:"mi", output:"\u03BB", ttype:CONST},
{input:"\\mu",		tag:"mi", output:"\u03BC", ttype:CONST},
{input:"\\nu",		tag:"mi", output:"\u03BD", ttype:CONST},
{input:"\\xi",		tag:"mi", output:"\u03BE", ttype:CONST},
{input:"\\pi",		tag:"mi", output:"\u03C0", ttype:CONST},
{input:"\\varpi",	tag:"mi", output:"\u03D6", ttype:CONST},
{input:"\\rho",		tag:"mi", output:"\u03C1", ttype:CONST},
{input:"\\varrho",	tag:"mi", output:"\u03F1", ttype:CONST},
{input:"\\varsigma",	tag:"mi", output:"\u03C2", ttype:CONST},
{input:"\\sigma",	tag:"mi", output:"\u03C3", ttype:CONST},
{input:"\\tau",		tag:"mi", output:"\u03C4", ttype:CONST},
{input:"\\upsilon",	tag:"mi", output:"\u03C5", ttype:CONST},
{input:"\\phi",		tag:"mi", output:"\u03C6", ttype:CONST},
{input:"\\varphi",	tag:"mi", output:"\u03D5", ttype:CONST},
{input:"\\chi",		tag:"mi", output:"\u03C7", ttype:CONST},
{input:"\\psi",		tag:"mi", output:"\u03C8", ttype:CONST},
{input:"\\omega",	tag:"mi", output:"\u03C9", ttype:CONST},
{input:"\\Gamma",	tag:"mo", output:"\u0393", ttype:CONST},
{input:"\\Delta",	tag:"mo", output:"\u0394", ttype:CONST},
{input:"\\Theta",	tag:"mo", output:"\u0398", ttype:CONST},
{input:"\\Lambda",	tag:"mo", output:"\u039B", ttype:CONST},
{input:"\\Xi",		tag:"mo", output:"\u039E", ttype:CONST},
{input:"\\Pi",		tag:"mo", output:"\u03A0", ttype:CONST},
{input:"\\Sigma",	tag:"mo", output:"\u03A3", ttype:CONST},
{input:"\\Upsilon",	tag:"mo", output:"\u03A5", ttype:CONST},
{input:"\\Phi",		tag:"mo", output:"\u03A6", ttype:CONST},
{input:"\\Psi",		tag:"mo", output:"\u03A8", ttype:CONST},
{input:"\\Omega",	tag:"mo", output:"\u03A9", ttype:CONST},

//fractions
{input:"\\frac12",	tag:"mo", output:"\u00BD", ttype:CONST},
{input:"\\frac14",	tag:"mo", output:"\u00BC", ttype:CONST},
{input:"\\frac34",	tag:"mo", output:"\u00BE", ttype:CONST},
{input:"\\frac13",	tag:"mo", output:"\u2153", ttype:CONST},
{input:"\\frac23",	tag:"mo", output:"\u2154", ttype:CONST},
{input:"\\frac15",	tag:"mo", output:"\u2155", ttype:CONST},
{input:"\\frac25",	tag:"mo", output:"\u2156", ttype:CONST},
{input:"\\frac35",	tag:"mo", output:"\u2157", ttype:CONST},
{input:"\\frac45",	tag:"mo", output:"\u2158", ttype:CONST},
{input:"\\frac16",	tag:"mo", output:"\u2159", ttype:CONST},
{input:"\\frac56",	tag:"mo", output:"\u215A", ttype:CONST},
{input:"\\frac18",	tag:"mo", output:"\u215B", ttype:CONST},
{input:"\\frac38",	tag:"mo", output:"\u215C", ttype:CONST},
{input:"\\frac58",	tag:"mo", output:"\u215D", ttype:CONST},
{input:"\\frac78",	tag:"mo", output:"\u215E", ttype:CONST},

//binary operation symbols
{input:"\\pm",		tag:"mo", output:"\u00B1", ttype:CONST},
{input:"\\mp",		tag:"mo", output:"\u2213", ttype:CONST},
{input:"\\triangleleft",tag:"mo", output:"\u22B2", ttype:CONST},
{input:"\\triangleright",tag:"mo",output:"\u22B3", ttype:CONST},
{input:"\\cdot",	tag:"mo", output:"\u22C5", ttype:CONST},
{input:"\\star",	tag:"mo", output:"\u22C6", ttype:CONST},
{input:"\\ast",		tag:"mo", output:"\u002A", ttype:CONST},
{input:"\\times",	tag:"mo", output:"\u00D7", ttype:CONST},
{input:"\\div",		tag:"mo", output:"\u00F7", ttype:CONST},
{input:"\\circ",	tag:"mo", output:"\u2218", ttype:CONST},
//{input:"\\bullet",	  tag:"mo", output:"\u2219", ttype:CONST},
{input:"\\bullet",	tag:"mo", output:"\u2022", ttype:CONST},
{input:"\\oplus",	tag:"mo", output:"\u2295", ttype:CONST},
{input:"\\ominus",	tag:"mo", output:"\u2296", ttype:CONST},
{input:"\\otimes",	tag:"mo", output:"\u2297", ttype:CONST},
{input:"\\bigcirc",	tag:"mo", output:"\u25CB", ttype:CONST},
{input:"\\oslash",	tag:"mo", output:"\u2298", ttype:CONST},
{input:"\\odot",	tag:"mo", output:"\u2299", ttype:CONST},
{input:"\\land",	tag:"mo", output:"\u2227", ttype:CONST},
{input:"\\wedge",	tag:"mo", output:"\u2227", ttype:CONST},
{input:"\\lor",		tag:"mo", output:"\u2228", ttype:CONST},
{input:"\\vee",		tag:"mo", output:"\u2228", ttype:CONST},
{input:"\\cap",		tag:"mo", output:"\u2229", ttype:CONST},
{input:"\\cup",		tag:"mo", output:"\u222A", ttype:CONST},
{input:"\\sqcap",	tag:"mo", output:"\u2293", ttype:CONST},
{input:"\\sqcup",	tag:"mo", output:"\u2294", ttype:CONST},
{input:"\\uplus",	tag:"mo", output:"\u228E", ttype:CONST},
{input:"\\amalg",	tag:"mo", output:"\u2210", ttype:CONST},
{input:"\\bigtriangleup",tag:"mo",output:"\u25B3", ttype:CONST},
{input:"\\bigtriangledown",tag:"mo",output:"\u25BD", ttype:CONST},
{input:"\\dag",		tag:"mo", output:"\u2020", ttype:CONST},
{input:"\\dagger",	tag:"mo", output:"\u2020", ttype:CONST},
{input:"\\ddag",	tag:"mo", output:"\u2021", ttype:CONST},
{input:"\\ddagger",	tag:"mo", output:"\u2021", ttype:CONST},
{input:"\\lhd",		tag:"mo", output:"\u22B2", ttype:CONST},
{input:"\\rhd",		tag:"mo", output:"\u22B3", ttype:CONST},
{input:"\\unlhd",	tag:"mo", output:"\u22B4", ttype:CONST},
{input:"\\unrhd",	tag:"mo", output:"\u22B5", ttype:CONST},


//BIG Operators
{input:"\\sum",		tag:"mo", output:"\u2211", ttype:UNDEROVER},
{input:"\\prod",	tag:"mo", output:"\u220F", ttype:UNDEROVER},
{input:"\\bigcap",	tag:"mo", output:"\u22C2", ttype:UNDEROVER},
{input:"\\bigcup",	tag:"mo", output:"\u22C3", ttype:UNDEROVER},
{input:"\\bigwedge",	tag:"mo", output:"\u22C0", ttype:UNDEROVER},
{input:"\\bigvee",	tag:"mo", output:"\u22C1", ttype:UNDEROVER},
{input:"\\bigsqcap",	tag:"mo", output:"\u2A05", ttype:UNDEROVER},
{input:"\\bigsqcup",	tag:"mo", output:"\u2A06", ttype:UNDEROVER},
{input:"\\coprod",	tag:"mo", output:"\u2210", ttype:UNDEROVER},
{input:"\\bigoplus",	tag:"mo", output:"\u2A01", ttype:UNDEROVER},
{input:"\\bigotimes",	tag:"mo", output:"\u2A02", ttype:UNDEROVER},
{input:"\\bigodot",	tag:"mo", output:"\u2A00", ttype:UNDEROVER},
{input:"\\biguplus",	tag:"mo", output:"\u2A04", ttype:UNDEROVER},
{input:"\\int",		tag:"mo", output:"\u222B", ttype:CONST},
{input:"\\oint",	tag:"mo", output:"\u222E", ttype:CONST},

//binary relation symbols
{input:":=",		tag:"mo", output:":=",	   ttype:CONST},
{input:"\\lt",		tag:"mo", output:"<",	   ttype:CONST},
{input:"\\gt",		tag:"mo", output:">",	   ttype:CONST},
{input:"\\ne",		tag:"mo", output:"\u2260", ttype:CONST},
{input:"\\neq",		tag:"mo", output:"\u2260", ttype:CONST},
{input:"\\le",		tag:"mo", output:"\u2264", ttype:CONST},
{input:"\\leq",		tag:"mo", output:"\u2264", ttype:CONST},
{input:"\\leqslant",	tag:"mo", output:"\u2264", ttype:CONST},
{input:"\\ge",		tag:"mo", output:"\u2265", ttype:CONST},
{input:"\\geq",		tag:"mo", output:"\u2265", ttype:CONST},
{input:"\\geqslant",	tag:"mo", output:"\u2265", ttype:CONST},
{input:"\\equiv",	tag:"mo", output:"\u2261", ttype:CONST},
{input:"\\ll",		tag:"mo", output:"\u226A", ttype:CONST},
{input:"\\gg",		tag:"mo", output:"\u226B", ttype:CONST},
{input:"\\doteq",	tag:"mo", output:"\u2250", ttype:CONST},
{input:"\\prec",	tag:"mo", output:"\u227A", ttype:CONST},
{input:"\\succ",	tag:"mo", output:"\u227B", ttype:CONST},
{input:"\\preceq",	tag:"mo", output:"\u227C", ttype:CONST},
{input:"\\succeq",	tag:"mo", output:"\u227D", ttype:CONST},
{input:"\\subset",	tag:"mo", output:"\u2282", ttype:CONST},
{input:"\\supset",	tag:"mo", output:"\u2283", ttype:CONST},
{input:"\\subseteq",	tag:"mo", output:"\u2286", ttype:CONST},
{input:"\\supseteq",	tag:"mo", output:"\u2287", ttype:CONST},
{input:"\\sqsubset",	tag:"mo", output:"\u228F", ttype:CONST},
{input:"\\sqsupset",	tag:"mo", output:"\u2290", ttype:CONST},
{input:"\\sqsubseteq",  tag:"mo", output:"\u2291", ttype:CONST},
{input:"\\sqsupseteq",  tag:"mo", output:"\u2292", ttype:CONST},
{input:"\\sim",		tag:"mo", output:"\u223C", ttype:CONST},
{input:"\\simeq",	tag:"mo", output:"\u2243", ttype:CONST},
{input:"\\approx",	tag:"mo", output:"\u2248", ttype:CONST},
{input:"\\cong",	tag:"mo", output:"\u2245", ttype:CONST},
{input:"\\Join",	tag:"mo", output:"\u22C8", ttype:CONST},
{input:"\\bowtie",	tag:"mo", output:"\u22C8", ttype:CONST},
{input:"\\in",		tag:"mo", output:"\u2208", ttype:CONST},
{input:"\\ni",		tag:"mo", output:"\u220B", ttype:CONST},
{input:"\\owns",	tag:"mo", output:"\u220B", ttype:CONST},
{input:"\\propto",	tag:"mo", output:"\u221D", ttype:CONST},
{input:"\\vdash",	tag:"mo", output:"\u22A2", ttype:CONST},
{input:"\\dashv",	tag:"mo", output:"\u22A3", ttype:CONST},
{input:"\\models",	tag:"mo", output:"\u22A8", ttype:CONST},
{input:"\\perp",	tag:"mo", output:"\u22A5", ttype:CONST},
{input:"\\smile",	tag:"mo", output:"\u2323", ttype:CONST},
{input:"\\frown",	tag:"mo", output:"\u2322", ttype:CONST},
{input:"\\asymp",	tag:"mo", output:"\u224D", ttype:CONST},
{input:"\\notin",	tag:"mo", output:"\u2209", ttype:CONST},

//matrices
{input:"\\begin{eqnarray}",	output:"X",	ttype:MATRIX, invisible:true},
{input:"\\begin{array}",	output:"X",	ttype:MATRIX, invisible:true},
{input:"\\\\",			output:"}&{",	ttype:DEFINITION},
{input:"\\end{eqnarray}",	output:"}}",	ttype:DEFINITION},
{input:"\\end{array}",		output:"}}",	ttype:DEFINITION},

//grouping and literal brackets -- ieval is for IE
{input:"\\big",	   tag:"mo", output:"X", atval:"1.2", ieval:"2.2", ttype:BIG},
{input:"\\Big",	   tag:"mo", output:"X", atval:"1.6", ieval:"2.6", ttype:BIG},
{input:"\\bigg",   tag:"mo", output:"X", atval:"2.2", ieval:"3.2", ttype:BIG},
{input:"\\Bigg",   tag:"mo", output:"X", atval:"2.9", ieval:"3.9", ttype:BIG},
{input:"\\left",   tag:"mo", output:"X", ttype:LEFTBRACKET},
{input:"\\right",  tag:"mo", output:"X", ttype:RIGHTBRACKET},
{input:"{",	   output:"{", ttype:LEFTBRACKET,  invisible:true},
{input:"}",	   output:"}", ttype:RIGHTBRACKET, invisible:true},

{input:"(",	   tag:"mo", output:"(",      atval:"1", ttype:STRETCHY},
{input:"[",	   tag:"mo", output:"[",      atval:"1", ttype:STRETCHY},
{input:"\\lbrack", tag:"mo", output:"[",      atval:"1", ttype:STRETCHY},
{input:"\\{",	   tag:"mo", output:"{",      atval:"1", ttype:STRETCHY},
{input:"\\lbrace", tag:"mo", output:"{",      atval:"1", ttype:STRETCHY},
{input:"\\langle", tag:"mo", output:"\u2329", atval:"1", ttype:STRETCHY},
{input:"\\lfloor", tag:"mo", output:"\u230A", atval:"1", ttype:STRETCHY},
{input:"\\lceil",  tag:"mo", output:"\u2308", atval:"1", ttype:STRETCHY},

// rtag:"mi" causes space to be inserted before a following sin, cos, etc.
// (see function LMparseExpr() )
{input:")",	  tag:"mo",output:")",	    rtag:"mi",atval:"1",ttype:STRETCHY},
{input:"]",	  tag:"mo",output:"]",	    rtag:"mi",atval:"1",ttype:STRETCHY},
{input:"\\rbrack",tag:"mo",output:"]",	    rtag:"mi",atval:"1",ttype:STRETCHY},
{input:"\\}",	  tag:"mo",output:"}",	    rtag:"mi",atval:"1",ttype:STRETCHY},
{input:"\\rbrace",tag:"mo",output:"}",	    rtag:"mi",atval:"1",ttype:STRETCHY},
{input:"\\rangle",tag:"mo",output:"\u232A", rtag:"mi",atval:"1",ttype:STRETCHY},
{input:"\\rfloor",tag:"mo",output:"\u230B", rtag:"mi",atval:"1",ttype:STRETCHY},
{input:"\\rceil", tag:"mo",output:"\u2309", rtag:"mi",atval:"1",ttype:STRETCHY},

// "|", "\\|", "\\vert" and "\\Vert" modified later: lspace = rspace = 0em
{input:"|",		tag:"mo", output:"\u2223", atval:"1", ttype:STRETCHY},
{input:"\\|",		tag:"mo", output:"\u2225", atval:"1", ttype:STRETCHY},
{input:"\\vert",	tag:"mo", output:"\u2223", atval:"1", ttype:STRETCHY},
{input:"\\Vert",	tag:"mo", output:"\u2225", atval:"1", ttype:STRETCHY},
{input:"\\mid",		tag:"mo", output:"\u2223", atval:"1", ttype:STRETCHY},
{input:"\\parallel",	tag:"mo", output:"\u2225", atval:"1", ttype:STRETCHY},
{input:"/",		tag:"mo", output:"/",	atval:"1.01", ttype:STRETCHY},
{input:"\\backslash",	tag:"mo", output:"\u2216", atval:"1", ttype:STRETCHY},
{input:"\\setminus",	tag:"mo", output:"\\",	   ttype:CONST},

//miscellaneous symbols
{input:"\\!",	  tag:"mspace", atname:"width", atval:"-0.167em", ttype:SPACE},
{input:"\\,",	  tag:"mspace", atname:"width", atval:"0.167em", ttype:SPACE},
{input:"\\>",	  tag:"mspace", atname:"width", atval:"0.222em", ttype:SPACE},
{input:"\\:",	  tag:"mspace", atname:"width", atval:"0.222em", ttype:SPACE},
{input:"\\;",	  tag:"mspace", atname:"width", atval:"0.278em", ttype:SPACE},
{input:"~",	  tag:"mspace", atname:"width", atval:"0.333em", ttype:SPACE},
{input:"\\quad",  tag:"mspace", atname:"width", atval:"1em", ttype:SPACE},
{input:"\\qquad", tag:"mspace", atname:"width", atval:"2em", ttype:SPACE},
//{input:"{}",		  tag:"mo", output:"\u200B", ttype:CONST}, // zero-width
{input:"\\prime",	tag:"mo", output:"\u2032", ttype:CONST},
{input:"'",		tag:"mo", output:"\u02B9", ttype:CONST},
{input:"''",		tag:"mo", output:"\u02BA", ttype:CONST},
{input:"'''",		tag:"mo", output:"\u2034", ttype:CONST},
{input:"''''",		tag:"mo", output:"\u2057", ttype:CONST},
{input:"\\ldots",	tag:"mo", output:"\u2026", ttype:CONST},
{input:"\\cdots",	tag:"mo", output:"\u22EF", ttype:CONST},
{input:"\\vdots",	tag:"mo", output:"\u22EE", ttype:CONST},
{input:"\\ddots",	tag:"mo", output:"\u22F1", ttype:CONST},
{input:"\\forall",	tag:"mo", output:"\u2200", ttype:CONST},
{input:"\\exists",	tag:"mo", output:"\u2203", ttype:CONST},
{input:"\\Re",		tag:"mo", output:"\u211C", ttype:CONST},
{input:"\\Im",		tag:"mo", output:"\u2111", ttype:CONST},
{input:"\\aleph",	tag:"mo", output:"\u2135", ttype:CONST},
{input:"\\hbar",	tag:"mo", output:"\u210F", ttype:CONST},
{input:"\\ell",		tag:"mo", output:"\u2113", ttype:CONST},
{input:"\\wp",		tag:"mo", output:"\u2118", ttype:CONST},
{input:"\\emptyset",	tag:"mo", output:"\u2205", ttype:CONST},
{input:"\\infty",	tag:"mo", output:"\u221E", ttype:CONST},
{input:"\\surd",	tag:"mo", output:"\\sqrt{}", ttype:DEFINITION},
{input:"\\partial",	tag:"mo", output:"\u2202", ttype:CONST},
{input:"\\nabla",	tag:"mo", output:"\u2207", ttype:CONST},
{input:"\\triangle",	tag:"mo", output:"\u25B3", ttype:CONST},
{input:"\\therefore",	tag:"mo", output:"\u2234", ttype:CONST},
{input:"\\angle",	tag:"mo", output:"\u2220", ttype:CONST},
//{input:"\\\\ ",	  tag:"mo", output:"\u00A0", ttype:CONST},
{input:"\\diamond",	tag:"mo", output:"\u22C4", ttype:CONST},
//{input:"\\Diamond",	  tag:"mo", output:"\u25CA", ttype:CONST},
{input:"\\Diamond",	tag:"mo", output:"\u25C7", ttype:CONST},
{input:"\\neg",		tag:"mo", output:"\u00AC", ttype:CONST},
{input:"\\lnot",	tag:"mo", output:"\u00AC", ttype:CONST},
{input:"\\bot",		tag:"mo", output:"\u22A5", ttype:CONST},
{input:"\\top",		tag:"mo", output:"\u22A4", ttype:CONST},
{input:"\\square",	tag:"mo", output:"\u25AB", ttype:CONST},
{input:"\\Box",		tag:"mo", output:"\u25A1", ttype:CONST},
{input:"\\wr",		tag:"mo", output:"\u2240", ttype:CONST},

//standard functions
//Note UNDEROVER *must* have tag:"mo" to work properly
{input:"\\arccos", tag:"mi", output:"arccos", ttype:UNARY, func:true},
{input:"\\arcsin", tag:"mi", output:"arcsin", ttype:UNARY, func:true},
{input:"\\arctan", tag:"mi", output:"arctan", ttype:UNARY, func:true},
{input:"\\arg",	   tag:"mi", output:"arg",    ttype:UNARY, func:true},
{input:"\\cos",	   tag:"mi", output:"cos",    ttype:UNARY, func:true},
{input:"\\cosh",   tag:"mi", output:"cosh",   ttype:UNARY, func:true},
{input:"\\cot",	   tag:"mi", output:"cot",    ttype:UNARY, func:true},
{input:"\\coth",   tag:"mi", output:"coth",   ttype:UNARY, func:true},
{input:"\\csc",	   tag:"mi", output:"csc",    ttype:UNARY, func:true},
{input:"\\deg",	   tag:"mi", output:"deg",    ttype:UNARY, func:true},
{input:"\\det",	   tag:"mi", output:"det",    ttype:UNARY, func:true},
{input:"\\dim",	   tag:"mi", output:"dim",    ttype:UNARY, func:true}, //CONST?
{input:"\\exp",	   tag:"mi", output:"exp",    ttype:UNARY, func:true},
{input:"\\gcd",	   tag:"mi", output:"gcd",    ttype:UNARY, func:true}, //CONST?
{input:"\\hom",	   tag:"mi", output:"hom",    ttype:UNARY, func:true},
{input:"\\inf",	      tag:"mo", output:"inf",	 ttype:UNDEROVER},
{input:"\\ker",	   tag:"mi", output:"ker",    ttype:UNARY, func:true},
{input:"\\lg",	   tag:"mi", output:"lg",     ttype:UNARY, func:true},
{input:"\\lim",	      tag:"mo", output:"lim",	 ttype:UNDEROVER},
{input:"\\liminf",    tag:"mo", output:"liminf", ttype:UNDEROVER},
{input:"\\limsup",    tag:"mo", output:"limsup", ttype:UNDEROVER},
{input:"\\ln",	   tag:"mi", output:"ln",     ttype:UNARY, func:true},
{input:"\\log",	   tag:"mi", output:"log",    ttype:UNARY, func:true},
{input:"\\max",	      tag:"mo", output:"max",	 ttype:UNDEROVER},
{input:"\\min",	      tag:"mo", output:"min",	 ttype:UNDEROVER},
{input:"\\Pr",	   tag:"mi", output:"Pr",     ttype:UNARY, func:true},
{input:"\\sec",	   tag:"mi", output:"sec",    ttype:UNARY, func:true},
{input:"\\sin",	   tag:"mi", output:"sin",    ttype:UNARY, func:true},
{input:"\\sinh",   tag:"mi", output:"sinh",   ttype:UNARY, func:true},
{input:"\\sup",	      tag:"mo", output:"sup",	 ttype:UNDEROVER},
{input:"\\tan",	   tag:"mi", output:"tan",    ttype:UNARY, func:true},
{input:"\\tanh",   tag:"mi", output:"tanh",   ttype:UNARY, func:true},

//arrows
{input:"\\gets",		tag:"mo", output:"\u2190", ttype:CONST},
{input:"\\leftarrow",		tag:"mo", output:"\u2190", ttype:CONST},
{input:"\\to",			tag:"mo", output:"\u2192", ttype:CONST},
{input:"\\rightarrow",		tag:"mo", output:"\u2192", ttype:CONST},
{input:"\\leftrightarrow",	tag:"mo", output:"\u2194", ttype:CONST},
{input:"\\uparrow",		tag:"mo", output:"\u2191", ttype:CONST},
{input:"\\downarrow",		tag:"mo", output:"\u2193", ttype:CONST},
{input:"\\updownarrow",		tag:"mo", output:"\u2195", ttype:CONST},
{input:"\\Leftarrow",		tag:"mo", output:"\u21D0", ttype:CONST},
{input:"\\Rightarrow",		tag:"mo", output:"\u21D2", ttype:CONST},
{input:"\\Leftrightarrow",	tag:"mo", output:"\u21D4", ttype:CONST},
{input:"\\iff", tag:"mo", output:"~\\Longleftrightarrow~", ttype:DEFINITION},
{input:"\\Uparrow",		tag:"mo", output:"\u21D1", ttype:CONST},
{input:"\\Downarrow",		tag:"mo", output:"\u21D3", ttype:CONST},
{input:"\\Updownarrow",		tag:"mo", output:"\u21D5", ttype:CONST},
{input:"\\mapsto",		tag:"mo", output:"\u21A6", ttype:CONST},
{input:"\\longleftarrow",	tag:"mo", output:"\u2190", ttype:LONG},
{input:"\\longrightarrow",	tag:"mo", output:"\u2192", ttype:LONG},
{input:"\\longleftrightarrow",	tag:"mo", output:"\u2194", ttype:LONG},
{input:"\\Longleftarrow",	tag:"mo", output:"\u21D0", ttype:LONG},
{input:"\\Longrightarrow",	tag:"mo", output:"\u21D2", ttype:LONG},
{input:"\\Longleftrightarrow",  tag:"mo", output:"\u21D4", ttype:LONG},
{input:"\\longmapsto",		tag:"mo", output:"\u21A6", ttype:CONST},
							// disaster if LONG

//commands with argument
LMsqrt, LMroot, LMfrac, LMover, LMsub, LMsup, LMtext, LMmbox, LMatop, LMchoose,
//LMdiv, LMquote,

//diacritical marks
{input:"\\acute",	tag:"mover",  output:"\u00B4", ttype:UNARY, acc:true},
//{input:"\\acute",	  tag:"mover",  output:"\u0317", ttype:UNARY, acc:true},
//{input:"\\acute",	  tag:"mover",  output:"\u0301", ttype:UNARY, acc:true},
//{input:"\\grave",	  tag:"mover",  output:"\u0300", ttype:UNARY, acc:true},
//{input:"\\grave",	  tag:"mover",  output:"\u0316", ttype:UNARY, acc:true},
{input:"\\grave",	tag:"mover",  output:"\u0060", ttype:UNARY, acc:true},
{input:"\\breve",	tag:"mover",  output:"\u02D8", ttype:UNARY, acc:true},
{input:"\\check",	tag:"mover",  output:"\u02C7", ttype:UNARY, acc:true},
{input:"\\dot",		tag:"mover",  output:".",      ttype:UNARY, acc:true},
{input:"\\ddot",	tag:"mover",  output:"..",     ttype:UNARY, acc:true},
//{input:"\\ddot",	  tag:"mover",  output:"\u00A8", ttype:UNARY, acc:true},
{input:"\\mathring",	tag:"mover",  output:"\u00B0", ttype:UNARY, acc:true},
{input:"\\vec",		tag:"mover",  output:"\u20D7", ttype:UNARY, acc:true},
{input:"\\overrightarrow",tag:"mover",output:"\u20D7", ttype:UNARY, acc:true},
{input:"\\overleftarrow",tag:"mover", output:"\u20D6", ttype:UNARY, acc:true},
{input:"\\hat",		tag:"mover",  output:"\u005E", ttype:UNARY, acc:true},
{input:"\\widehat",	tag:"mover",  output:"\u0302", ttype:UNARY, acc:true},
{input:"\\tilde",	tag:"mover",  output:"~",      ttype:UNARY, acc:true},
//{input:"\\tilde",	  tag:"mover",  output:"\u0303", ttype:UNARY, acc:true},
{input:"\\widetilde",	tag:"mover",  output:"\u02DC", ttype:UNARY, acc:true},
{input:"\\bar",		tag:"mover",  output:"\u203E", ttype:UNARY, acc:true},
{input:"\\overbrace",	tag:"mover",  output:"\u23B4", ttype:UNARY, acc:true},
{input:"\\overline",	tag:"mover",  output:"\u00AF", ttype:UNARY, acc:true},
{input:"\\underbrace",  tag:"munder", output:"\u23B5", ttype:UNARY, acc:true},
{input:"\\underline",	tag:"munder", output:"\u00AF", ttype:UNARY, acc:true},
//{input:"underline",	tag:"munder", output:"\u0332", ttype:UNARY, acc:true},

//typestyles and fonts
{input:"\\displaystyle",tag:"mstyle",atname:"displaystyle",atval:"true", ttype:UNARY},
{input:"\\textstyle",tag:"mstyle",atname:"displaystyle",atval:"false", ttype:UNARY},
{input:"\\scriptstyle",tag:"mstyle",atname:"scriptlevel",atval:"1", ttype:UNARY},
{input:"\\scriptscriptstyle",tag:"mstyle",atname:"scriptlevel",atval:"2", ttype:UNARY},
{input:"\\textrm", tag:"mstyle", output:"\\mathrm", ttype: DEFINITION},
{input:"\\mathbf", tag:"mstyle", atname:"mathvariant", atval:"bold", ttype:UNARY},
{input:"\\textbf", tag:"mstyle", atname:"mathvariant", atval:"bold", ttype:UNARY},
{input:"\\mathit", tag:"mstyle", atname:"mathvariant", atval:"italic", ttype:UNARY},
{input:"\\textit", tag:"mstyle", atname:"mathvariant", atval:"italic", ttype:UNARY},
{input:"\\mathtt", tag:"mstyle", atname:"mathvariant", atval:"monospace", ttype:UNARY},
{input:"\\texttt", tag:"mstyle", atname:"mathvariant", atval:"monospace", ttype:UNARY},
{input:"\\mathsf", tag:"mstyle", atname:"mathvariant", atval:"sans-serif", ttype:UNARY},
{input:"\\mathbb", tag:"mstyle", atname:"mathvariant", atval:"double-struck", ttype:UNARY, codes:LMbbb},
{input:"\\mathcal",tag:"mstyle", atname:"mathvariant", atval:"script", ttype:UNARY, codes:LMcal},
{input:"\\mathfrak",tag:"mstyle",atname:"mathvariant", atval:"fraktur",ttype:UNARY, codes:LMfrk}
];

function compareNames(s1,s2) {
  if (s1.input > s2.input) return 1
  else return -1;
}

var LMnames = []; //list of input symbols

function LMinitSymbols() {
  LMsymbols.sort(compareNames);
  for (i=0; i<LMsymbols.length; i++) LMnames[i] = LMsymbols[i].input;
}

var LMmathml = "http://www.w3.org/1998/Math/MathML";

function LMcreateElementMathML(t) {
  if (isIE) return document.createElement("m:"+t);
  else return document.createElementNS(LMmathml,t);
}

function LMcreateMmlNode(t,frag) {
//  var node = LMcreateElementMathML(name);
  if (isIE) var node = document.createElement("m:"+t);
  else var node = document.createElementNS(LMmathml,t);
  node.appendChild(frag);
  return node;
}

function newcommand(oldstr,newstr) {
  LMsymbols = LMsymbols.concat([{input:oldstr, tag:"mo", output:newstr,
                                 ttype:DEFINITION}]);
}

function LMremoveCharsAndBlanks(str,n) {
//remove n characters and any following blanks
  var st;
  st = str.slice(n);
  for (var i=0; i<st.length && st.charCodeAt(i)<=32; i=i+1);
  return st.slice(i);
}

function LMposition(arr, str, n) {
// return position >=n where str appears or would be inserted
// assumes arr is sorted
  if (n==0) {
    var h,m;
    n = -1;
    h = arr.length;
    while (n+1<h) {
      m = (n+h) >> 1;
      if (arr[m]<str) n = m; else h = m;
    }
    return h;
  } else
    for (var i=n; i<arr.length && arr[i]<str; i++);
  return i; // i=arr.length || arr[i]>=str
}

function LMgetSymbol(str) {
//return maximal initial substring of str that appears in names
//return null if there is none
  var k = 0; //new pos
  var j = 0; //old pos
  var mk; //match pos
  var st;
  var tagst;
  var match = "";
  var more = true;
  for (var i=1; i<=str.length && more; i++) {
    st = str.slice(0,i); //initial substring of length i
    j = k;
    k = LMposition(LMnames, st, j);
    if (k<LMnames.length && str.slice(0,LMnames[k].length)==LMnames[k]){
      match = LMnames[k];
      mk = k;
      i = match.length;
    }
    more = k<LMnames.length && str.slice(0,LMnames[k].length)>=LMnames[k];
  }
  LMpreviousSymbol=LMcurrentSymbol;
  if (match!=""){
    LMcurrentSymbol=LMsymbols[mk].ttype;
    return LMsymbols[mk];
  }
  LMcurrentSymbol=CONST;
  k = 1;
  st = str.slice(0,1); //take 1 character
  if ("0"<=st && st<="9") tagst = "mn";
  else tagst = (("A">st || st>"Z") && ("a">st || st>"z")?"mo":"mi");
/*
// Commented out by DRW (not fully understood, but probably to do with
// use of "/" as an INFIX version of "\\frac", which we don't want):
//}
//if (st=="-" && LMpreviousSymbol==INFIX) {
//  LMcurrentSymbol = INFIX;  //trick "/" into recognizing "-" on second parse
//  return {input:st, tag:tagst, output:st, ttype:UNARY, func:true};
//}
*/
  return {input:st, tag:tagst, output:st, ttype:CONST};
}


/*Parsing ASCII math expressions with the following grammar
v ::= [A-Za-z] | greek letters | numbers | other constant symbols
u ::= sqrt | text | bb | other unary symbols for font commands
b ::= frac | root | stackrel	binary symbols
l ::= { | \left			left brackets
r ::= } | \right		right brackets
S ::= v | lEr | uS | bSS	Simple expression
I ::= S_S | S^S | S_S^S | S	Intermediate expression
E ::= IE | I/I			Expression
Each terminal symbol is translated into a corresponding mathml node.*/

var LMpreviousSymbol,LMcurrentSymbol;

function LMparseSexpr(str) { //parses str and returns [node,tailstr,(node)tag]
  var symbol, node, result, result2, i, st,// rightvert = false,
    newFrag = document.createDocumentFragment();
  str = LMremoveCharsAndBlanks(str,0);
  symbol = LMgetSymbol(str);             //either a token or a bracket or empty
  if (symbol == null || symbol.ttype == RIGHTBRACKET)
    return [null,str,null];
  if (symbol.ttype == DEFINITION) {
    str = symbol.output+LMremoveCharsAndBlanks(str,symbol.input.length);
    symbol = LMgetSymbol(str);
    if (symbol == null || symbol.ttype == RIGHTBRACKET)
      return [null,str,null];
  }
  str = LMremoveCharsAndBlanks(str,symbol.input.length);
  switch (symbol.ttype) {
  case SPACE:
    node = LMcreateElementMathML(symbol.tag);
    node.setAttribute(symbol.atname,symbol.atval);
    return [node,str,symbol.tag];
  case UNDEROVER:
    if (isIE) {
      if (symbol.input.substr(0,4) == "\\big") {   // botch for missing symbols
	str = "\\"+symbol.input.substr(4)+str;	   // make \bigcup = \cup etc.
	symbol = LMgetSymbol(str);
	symbol.ttype = UNDEROVER;
	str = LMremoveCharsAndBlanks(str,symbol.input.length);
      }
    }
    return [LMcreateMmlNode(symbol.tag,
			document.createTextNode(symbol.output)),str,symbol.tag];
  case CONST:
    var output = symbol.output;
    if (isIE) {
      if (symbol.input == "'")
	output = "\u2032";
      else if (symbol.input == "''")
	output = "\u2033";
      else if (symbol.input == "'''")
	output = "\u2033\u2032";
      else if (symbol.input == "''''")
	output = "\u2033\u2033";
      else if (symbol.input == "\\square")
	output = "\u25A1";	// same as \Box
      else if (symbol.input.substr(0,5) == "\\frac") {
						// botch for missing fractions
	var denom = symbol.input.substr(6,1);
	if (denom == "5" || denom == "6") {
	  str = symbol.input.replace(/\\frac/,"\\frac ")+str;
	  return [node,str,symbol.tag];
	}
      }
    }
    node = LMcreateMmlNode(symbol.tag,document.createTextNode(output));
    return [node,str,symbol.tag];
  case LONG:  // added by DRW
    node = LMcreateMmlNode(symbol.tag,document.createTextNode(symbol.output));
    node.setAttribute("minsize","1.5");
    node.setAttribute("maxsize","1.5");
    node = LMcreateMmlNode("mover",node);
    node.appendChild(LMcreateElementMathML("mspace"));
    return [node,str,symbol.tag];
  case STRETCHY:  // added by DRW
    if (isIE && symbol.input == "\\backslash")
	symbol.output = "\\";	// doesn't expand, but then nor does "\u2216"
    node = LMcreateMmlNode(symbol.tag,document.createTextNode(symbol.output));
    if (symbol.input == "|" || symbol.input == "\\vert" ||
	symbol.input == "\\|" || symbol.input == "\\Vert") {
	  node.setAttribute("lspace","0em");
	  node.setAttribute("rspace","0em");
    }
    node.setAttribute("maxsize",symbol.atval);  // don't allow to stretch here
    if (symbol.rtag != null)
      return [node,str,symbol.rtag];
    else
      return [node,str,symbol.tag];
  case BIG:  // added by DRW
    var atval = symbol.atval;
    if (isIE)
      atval = symbol.ieval;
    symbol = LMgetSymbol(str);
    if (symbol == null)
	return [null,str,null];
    str = LMremoveCharsAndBlanks(str,symbol.input.length);
    node = LMcreateMmlNode(symbol.tag,document.createTextNode(symbol.output));
    if (isIE) {		// to get brackets to expand
      var space = LMcreateElementMathML("mspace");
      space.setAttribute("height",atval+"ex");
      node = LMcreateMmlNode("mrow",node);
      node.appendChild(space);
    } else {		// ignored in IE
      node.setAttribute("minsize",atval);
      node.setAttribute("maxsize",atval);
    }
    return [node,str,symbol.tag];
  case LEFTBRACKET:   //read (expr+)
    if (symbol.input == "\\left") { // left what?
      symbol = LMgetSymbol(str);
      if (symbol != null) {
	if (symbol.input == ".")
	  symbol.invisible = true;
	str = LMremoveCharsAndBlanks(str,symbol.input.length);
      }
    }
    result = LMparseExpr(str,true,false);
    if (symbol==null ||
	(typeof symbol.invisible == "boolean" && symbol.invisible))
      node = LMcreateMmlNode("mrow",result[0]);
    else {
      node = LMcreateMmlNode("mo",document.createTextNode(symbol.output));
      node = LMcreateMmlNode("mrow",node);
      node.appendChild(result[0]);
    }
    return [node,result[1],result[2]];
  case MATRIX:	 //read (expr+)
    if (symbol.input == "\\begin{array}") {
      var mask = "";
      symbol = LMgetSymbol(str);
      str = LMremoveCharsAndBlanks(str,0);
      if (symbol == null)
	mask = "l";
      else {
	str = LMremoveCharsAndBlanks(str,symbol.input.length);
	if (symbol.input != "{")
	  mask = "l";
	else do {
	  symbol = LMgetSymbol(str);
	  if (symbol != null) {
	    str = LMremoveCharsAndBlanks(str,symbol.input.length);
	    if (symbol.input != "}")
	      mask = mask+symbol.input;
	  }
	} while (symbol != null && symbol.input != "" && symbol.input != "}");
      }
      result = LMparseExpr("{"+str,true,true);
//    if (result[0]==null) return [LMcreateMmlNode("mo",
//			   document.createTextNode(symbol.input)),str];
      node = LMcreateMmlNode("mtable",result[0]);
      mask = mask.replace(/l/g,"left ");
      mask = mask.replace(/r/g,"right ");
      mask = mask.replace(/c/g,"center ");
      node.setAttribute("columnalign",mask);
      node.setAttribute("displaystyle","false");
      if (isIE)
	return [node,result[1],null];
// trying to get a *little* bit of space around the array
// (IE already includes it)
      var lspace = LMcreateElementMathML("mspace");
      lspace.setAttribute("width","0.167em");
      var rspace = LMcreateElementMathML("mspace");
      rspace.setAttribute("width","0.167em");
      var node1 = LMcreateMmlNode("mrow",lspace);
      node1.appendChild(node);
      node1.appendChild(rspace);
      return [node1,result[1],null];
    } else {	// eqnarray
      result = LMparseExpr("{"+str,true,true);
      node = LMcreateMmlNode("mtable",result[0]);
      if (isIE)
	node.setAttribute("columnspacing","0.25em"); // best in practice?
      else
	node.setAttribute("columnspacing","0.167em"); // correct (but ignored?)
      node.setAttribute("columnalign","right center left");
      node.setAttribute("displaystyle","true");
      node = LMcreateMmlNode("mrow",node);
      return [node,result[1],null];
    }
  case TEXT:
      if (str.charAt(0)=="{") i=str.indexOf("}");
      else i = 0;
      if (i==-1)
		 i = str.length;
      st = str.slice(1,i);
      if (st.charAt(0) == " ") {
	node = LMcreateElementMathML("mspace");
	node.setAttribute("width","0.33em");	// was 1ex
	newFrag.appendChild(node);
      }
      newFrag.appendChild(
        LMcreateMmlNode(symbol.tag,document.createTextNode(st)));
      if (st.charAt(st.length-1) == " ") {
	node = LMcreateElementMathML("mspace");
	node.setAttribute("width","0.33em");	// was 1ex
	newFrag.appendChild(node);
      }
      str = LMremoveCharsAndBlanks(str,i+1);
      return [LMcreateMmlNode("mrow",newFrag),str,null];
  case UNARY:
      result = LMparseSexpr(str);
      if (result[0]==null) return [LMcreateMmlNode(symbol.tag,
                             document.createTextNode(symbol.output)),str];
      if (typeof symbol.func == "boolean" && symbol.func) { // functions hack
	st = str.charAt(0);
//	if (st=="^" || st=="_" || st=="/" || st=="|" || st==",") {
	if (st=="^" || st=="_" || st==",") {
	  return [LMcreateMmlNode(symbol.tag,
		    document.createTextNode(symbol.output)),str,symbol.tag];
        } else {
	  node = LMcreateMmlNode("mrow",
	   LMcreateMmlNode(symbol.tag,document.createTextNode(symbol.output)));
	  if (isIE) {
	    var space = LMcreateElementMathML("mspace");
	    space.setAttribute("width","0.167em");
	    node.appendChild(space);
	  }
	  node.appendChild(result[0]);
	  return [node,result[1],symbol.tag];
        }
      }
      if (symbol.input == "\\sqrt") {		// sqrt
	if (isIE) {	// set minsize, for \surd
	  var space = LMcreateElementMathML("mspace");
	  space.setAttribute("height","1.2ex");
	  space.setAttribute("width","0em");	// probably no effect
	  node = LMcreateMmlNode(symbol.tag,result[0])
//	  node.setAttribute("minsize","1");	// ignored
//	  node = LMcreateMmlNode("mrow",node);  // hopefully unnecessary
	  node.appendChild(space);
	  return [node,result[1],symbol.tag];
	} else
	  return [LMcreateMmlNode(symbol.tag,result[0]),result[1],symbol.tag];
      } else if (typeof symbol.acc == "boolean" && symbol.acc) {   // accent
        node = LMcreateMmlNode(symbol.tag,result[0]);
	var output = symbol.output;
	if (isIE) {
		if (symbol.input == "\\hat")
			output = "\u0302";
		else if (symbol.input == "\\widehat")
			output = "\u005E";
		else if (symbol.input == "\\bar")
			output = "\u00AF";
		else if (symbol.input == "\\grave")
			output = "\u0300";
		else if (symbol.input == "\\tilde")
			output = "\u0303";
	}
	var node1 = LMcreateMmlNode("mo",document.createTextNode(output));
	if (symbol.input == "\\vec" || symbol.input == "\\check")
						// don't allow to stretch
	    node1.setAttribute("maxsize","1.2");
		 // why doesn't "1" work?  \vec nearly disappears in firefox
	if (isIE && symbol.input == "\\bar")
	    node1.setAttribute("maxsize","0.5");
	if (symbol.input == "\\underbrace" || symbol.input == "\\underline")
	  node1.setAttribute("accentunder","true");
	else
	  node1.setAttribute("accent","true");
	node.appendChild(node1);
	if (symbol.input == "\\overbrace" || symbol.input == "\\underbrace")
	  node.ttype = UNDEROVER;
	return [node,result[1],symbol.tag];
      } else {			      // font change or displaystyle command
        if (!isIE && typeof symbol.codes != "undefined") {
          for (i=0; i<result[0].childNodes.length; i++)
            if (result[0].childNodes[i].nodeName=="mi" || result[0].nodeName=="mi") {
              st = (result[0].nodeName=="mi"?result[0].firstChild.nodeValue:
                              result[0].childNodes[i].firstChild.nodeValue);
              var newst = [];
              for (var j=0; j<st.length; j++)
                if (st.charCodeAt(j)>64 && st.charCodeAt(j)<91) newst = newst +
                  String.fromCharCode(symbol.codes[st.charCodeAt(j)-65]);
                else newst = newst + st.charAt(j);
              if (result[0].nodeName=="mi")
                result[0]=LMcreateElementMathML("mo").
                          appendChild(document.createTextNode(newst));
              else result[0].replaceChild(LMcreateElementMathML("mo").
          appendChild(document.createTextNode(newst)),result[0].childNodes[i]);
            }
        }
        node = LMcreateMmlNode(symbol.tag,result[0]);
        node.setAttribute(symbol.atname,symbol.atval);
	if (symbol.input == "\\scriptstyle" ||
	    symbol.input == "\\scriptscriptstyle")
		node.setAttribute("displaystyle","false");
	return [node,result[1],symbol.tag];
      }
  case BINARY:
    result = LMparseSexpr(str);
    if (result[0]==null) return [LMcreateMmlNode("mo",
			   document.createTextNode(symbol.input)),str,null];
    result2 = LMparseSexpr(result[1]);
    if (result2[0]==null) return [LMcreateMmlNode("mo",
			   document.createTextNode(symbol.input)),str,null];
    if (symbol.input=="\\root" || symbol.input=="\\stackrel")
      newFrag.appendChild(result2[0]);
    newFrag.appendChild(result[0]);
    if (symbol.input=="\\frac") newFrag.appendChild(result2[0]);
    return [LMcreateMmlNode(symbol.tag,newFrag),result2[1],symbol.tag];
  case INFIX:
    str = LMremoveCharsAndBlanks(str,symbol.input.length);
    return [LMcreateMmlNode("mo",document.createTextNode(symbol.output)),
	str,symbol.tag];
  default:
    return [LMcreateMmlNode(symbol.tag,        //its a constant
	document.createTextNode(symbol.output)),str,symbol.tag];
  }
}

function LMparseIexpr(str) {
  var symbol, sym1, sym2, node, result, tag, underover;
  str = LMremoveCharsAndBlanks(str,0);
  sym1 = LMgetSymbol(str);
  result = LMparseSexpr(str);
  node = result[0];
  str = result[1];
  tag = result[2];
  symbol = LMgetSymbol(str);
  if (symbol.ttype == INFIX) {
    str = LMremoveCharsAndBlanks(str,symbol.input.length);
    result = LMparseSexpr(str);
    if (result[0] == null) // show box in place of missing argument
      result[0] = LMcreateMmlNode("mo",document.createTextNode("\u25A1"));
    str = result[1];
    tag = result[2];
    if (symbol.input == "_" || symbol.input == "^") {
      sym2 = LMgetSymbol(str);
      tag = null;	// no space between x^2 and a following sin, cos, etc.
// This is for \underbrace and \overbrace
      underover = ((sym1.ttype == UNDEROVER) || (node.ttype == UNDEROVER));
//    underover = (sym1.ttype == UNDEROVER);
      if (symbol.input == "_" && sym2.input == "^") {
        str = LMremoveCharsAndBlanks(str,sym2.input.length);
        var res2 = LMparseSexpr(str);
	str = res2[1];
	tag = res2[2];  // leave space between x_1^2 and a following sin etc.
        node = LMcreateMmlNode((underover?"munderover":"msubsup"),node);
        node.appendChild(result[0]);
        node.appendChild(res2[0]);
      } else if (symbol.input == "_") {
	node = LMcreateMmlNode((underover?"munder":"msub"),node);
        node.appendChild(result[0]);
      } else {
	node = LMcreateMmlNode((underover?"mover":"msup"),node);
        node.appendChild(result[0]);
      }
      node = LMcreateMmlNode("mrow",node); // so sum does not stretch
    } else {
      node = LMcreateMmlNode(symbol.tag,node);
      if (symbol.input == "\\atop" || symbol.input == "\\choose")
	node.setAttribute("linethickness","0ex");
      node.appendChild(result[0]);
      if (symbol.input == "\\choose")
	node = LMcreateMmlNode("mfenced",node);
    }
  }
  return [node,str,tag];
}

function LMparseExpr(str,rightbracket,matrix) {
  var symbol, node, result, i, tag,
  newFrag = document.createDocumentFragment();
  do {
    str = LMremoveCharsAndBlanks(str,0);
    result = LMparseIexpr(str);
    node = result[0];
    str = result[1];
    tag = result[2];
    symbol = LMgetSymbol(str);
    if (node!=undefined) {
      if ((tag == "mn" || tag == "mi") && symbol!=null &&
	typeof symbol.func == "boolean" && symbol.func) {
			// Add space before \sin in 2\sin x or x\sin x
	  var space = LMcreateElementMathML("mspace");
	  space.setAttribute("width","0.167em");
	  node = LMcreateMmlNode("mrow",node);
	  node.appendChild(space);
      }
      newFrag.appendChild(node);
    }
  } while ((symbol.ttype != RIGHTBRACKET)
        && symbol!=null && symbol.output!="");
  tag = null;
  if (symbol.ttype == RIGHTBRACKET) {
    if (symbol.input == "\\right") { // right what?
      str = LMremoveCharsAndBlanks(str,symbol.input.length);
      symbol = LMgetSymbol(str);
      if (symbol != null && symbol.input == ".")
	symbol.invisible = true;
      if (symbol != null)
	tag = symbol.rtag;
    }
    if (symbol!=null)
      str = LMremoveCharsAndBlanks(str,symbol.input.length); // ready to return
    var len = newFrag.childNodes.length;
    if (matrix &&
      len>0 && newFrag.childNodes[len-1].nodeName == "mrow" && len>1 &&
      newFrag.childNodes[len-2].nodeName == "mo" &&
      newFrag.childNodes[len-2].firstChild.nodeValue == "&") { //matrix
	var pos = []; // positions of ampersands
        var m = newFrag.childNodes.length;
        for (i=0; matrix && i<m; i=i+2) {
          pos[i] = [];
          node = newFrag.childNodes[i];
	  for (var j=0; j<node.childNodes.length; j++)
	    if (node.childNodes[j].firstChild.nodeValue=="&")
	      pos[i][pos[i].length]=j;
        }
	var row, frag, n, k, table = document.createDocumentFragment();
	for (i=0; i<m; i=i+2) {
	  row = document.createDocumentFragment();
	  frag = document.createDocumentFragment();
	  node = newFrag.firstChild; // <mrow> -&-&...&-&- </mrow>
	  n = node.childNodes.length;
	  k = 0;
	  for (j=0; j<n; j++) {
	    if (typeof pos[i][k] != "undefined" && j==pos[i][k]){
	      node.removeChild(node.firstChild); //remove &
	      row.appendChild(LMcreateMmlNode("mtd",frag));
	      k++;
	    } else frag.appendChild(node.firstChild);
	  }
	  row.appendChild(LMcreateMmlNode("mtd",frag));
	  if (newFrag.childNodes.length>2) {
	    newFrag.removeChild(newFrag.firstChild); //remove <mrow> </mrow>
	    newFrag.removeChild(newFrag.firstChild); //remove <mo>&</mo>
	  }
	  table.appendChild(LMcreateMmlNode("mtr",row));
	}
	return [table,str];
    }
    if (typeof symbol.invisible != "boolean" || !symbol.invisible) {
      node = LMcreateMmlNode("mo",document.createTextNode(symbol.output));
      newFrag.appendChild(node);
    }
  }
  return [newFrag,str,tag];
}

function LMparseMath(str) {
  var result, node = LMcreateElementMathML("mstyle");
  if (LMmathcolor != "") node.setAttribute("mathcolor",LMmathcolor);
  if (LMmathfontfamily != "") node.setAttribute("fontfamily",LMmathfontfamily);
  node.appendChild(LMparseExpr(str.replace(/^\s+/g,""),false,false)[0]);
  node = LMcreateMmlNode("math",node);
  if (LMshowasciiformulaonhover)                    //fixed by djhsu so newline
    node.setAttribute("title",str.replace(/\s+/g," "));//does not show in Gecko
  var fnode = LMcreateElementXHTML("span");
  fnode.style.fontSize = mathfontsize;
  if (LMmathfontfamily != "") fnode.style.fontFamily = LMmathfontfamily;
  fnode.appendChild(node);
  return fnode;
}

function LMstrarr2docFrag(arr, linebreaks) {
  var newFrag=document.createDocumentFragment();
  var expr = false;
  for (var i=0; i<arr.length; i++) {
    if (expr) newFrag.appendChild(LMparseMath(arr[i]));
    else {
      var arri = (linebreaks ? arr[i].split("\n\n") : [arr[i]]);
      newFrag.appendChild(LMcreateElementXHTML("span").
      appendChild(document.createTextNode(arri[0])));
      for (var j=1; j<arri.length; j++) {
        newFrag.appendChild(LMcreateElementXHTML("p"));
        newFrag.appendChild(LMcreateElementXHTML("span").
        appendChild(document.createTextNode(arri[j])));
      }
    }
    expr = !expr;
  }
  return newFrag;
}

function LMprocessNodeR(n, linebreaks) {
  var mtch, str, arr, frg, i;
  if (n.childNodes.length == 0) {
   if ((n.nodeType!=8 || linebreaks) &&
    n.parentNode.nodeName!="form" && n.parentNode.nodeName!="FORM" &&
    n.parentNode.nodeName!="textarea" && n.parentNode.nodeName!="TEXTAREA" &&
    n.parentNode.nodeName!="pre" && n.parentNode.nodeName!="PRE") {
    str = n.nodeValue;
    if (!(str == null)) {
      str = str.replace(/\r\n\r\n/g,"\n\n");
      str = str.replace(/\x20+/g," ");
      str = str.replace(/\s*\r\n/g," ");
// DELIMITERS:
      mtch = (str.indexOf("\$")==-1 ? false : true);
      str = str.replace(/([^\\])\$/g,"$1 \$");
      str = str.replace(/^\$/," \$");	// in case \$ at start of string
      arr = str.split(" \$");
      for (i=0; i<arr.length; i++)
	arr[i]=arr[i].replace(/\\\$/g,"\$");
      if (arr.length>1 || mtch) {
        if (LMcheckForMathML) {
          LMcheckForMathML = false;
          var nd = LMisMathMLavailable();
          LMnoMathML = nd != null;
          if (LMnoMathML && LMnotifyIfNoMathML)
            if (LMalertIfNoMathML)
              alert("To view the ASCIIMathML notation use Internet Explorer 6 +\nMathPlayer (free from www.dessci.com)\n\
                or Firefox/Mozilla/Netscape");
            else LMbody.insertBefore(nd,LMbody.childNodes[0]);
        }
        if (!LMnoMathML) {
          frg = LMstrarr2docFrag(arr,n.nodeType==8);
          var len = frg.childNodes.length;
          n.parentNode.replaceChild(frg,n);
          return len-1;
        } else return 0;
      }
    }
   } else return 0;
  } else if (n.nodeName!="math") {
    for (i=0; i<n.childNodes.length; i++)
      i += LMprocessNodeR(n.childNodes[i], linebreaks);
  }
  return 0;
}

var tcnt = 0, dcnt = 0; //theorem and definition counters

function simpleLaTeXformatting(st) {
  st = st.replace(/\$\$(.*?)\$\$/g,"<p align=\"center\">$\\displaystyle{$1}$</p>");
  st = st.replace(/\\begin{(theorem|lemma|proposition|corollary)}((.|\n)*?)\\end{\1}/g,function(r,s,t){tcnt++; return "<b>"+s.charAt(0).toUpperCase()+s.slice(1)+" "+tcnt+".</b> <i>"+t.replace(/^\s*<\/?\w+\/?>|\s*<\/?\w+\/?>$/g,"")+"</i>"});
  st = st.replace(/\\begin{(definition|example|remark|problem|exercise|conjecture|solution)}((.|\n)*?)\\end{\1}/g,function(r,s,t){dcnt++; return "<b>"+s.charAt(0).toUpperCase()+s.slice(1)+" "+dcnt+".</b> "+t.replace(/^\s*<\/?\w+\/?>|\s*<\/?\w+\/?>$/g,"")});
  st = st.replace(/\\begin{proof}((.|\n)*?)\\end{proof}/g,function(s,t){return "<i>Proof:</i> "+t.replace(/^\s*<\/?\w+\/?>|\s*<\/?\w+\/?>$/g,"")+" &#x25A1;"});
  st = st.replace(/\\emph{(.*?)}/g,"<em>$1</em>");
  st = st.replace(/\\textbf{(.*?)}/g,"<b>$1</b>");
  st = st.replace(/\\cite{(.*?)}/g,"[$1]");
  st = st.replace(/\\chapter{(.*?)}/g,"<h2>$1</h2>");
  st = st.replace(/\\section{(.*?)}(\s*<\/?(br|p)\s?\/?>)?/g,"<h3>$1</h3>");
  st = st.replace(/\\subsection{(.*?)}/g,"<h4>$1</h4>");
  st = st.replace(/\\begin{itemize}(\s*<\/?(br|p)\s?\/?>)?/g,"<ul>");
  st = st.replace(/\\item\s((.|\n)*?)(?=(\\item|\\end))/g,"<li>$1</li>");
  st = st.replace(/\\end{itemize}(\s*<\/?(br|p)\s?\/?>)?/g,"</ul>");
  st = st.replace(/\\begin{enumerate}(\s*<\/?(br|p)\s?\/?>)?/g,"<ol>");
  st = st.replace(/\\end{enumerate}(\s*<\/?(br|p)\s?\/?>)?/g,"</ol>");
  st = st.replace(/\\item\[(.*?)]{(.*?)}/g,"<dt>$1</dt><dd>$2</dd>");
  st = st.replace(/\\begin{description}/g,"<dl>");
  st = st.replace(/\\end{description}/g,"</dl>");
  st = st.replace(/\\newline\b/g,"<br/>");
  st = st.replace(/\\newpage\b/g,"<br style=\"page-break-after:always;\">");
  st = st.replace(/\\par\b/g,"<p>&nbsp;</p>");
  st = st.replace(/\\bigskip/g,"<p style=\"margin-bottom:0.5in\">&nbsp;</p>");
  st = st.replace(/\\medskip/g,"<p style=\"margin-bottom:0.3in\">&nbsp;</p>");
  st = st.replace(/\\smallskip/g,"<p style=\"margin-bottom:0.15in\">&nbsp;</p>");
  st = st.replace(/\\begin{center}(.*?)\\end{center}/g,"<p align=\"center\">$1</p>");
  st = st.replace(/<embed\s+class\s?=\s?"ASCIIsvg"/g,"<embed class=\"ASCIIsvg\" src=\""+dsvglocation+"d.svg\" wmode=\"transparent\"");
  st = st.replace(/(?:\\begin{a?graph}|agraph|\(:graph\s)((.|\n)*?)(?:\\end{a?graph}|enda?graph|:\))/g,function(s,t){return "<div><embed class=\"ASCIIsvg\" src=\""+dsvglocation+"d.svg\" wmode=\"transparent\" script=\'"+t.replace(/<\/?(br|p|pre)\s?\/?>/gi,"\n")+"\'/></div>"});
//  st = st.replace(/\(:graph((.|\n)*?):\)/g,function(s,t){return "<div><embed class=\"ASCIIsvg\" src=\""+dsvglocation+"d.svg\" wmode=\"transparent\" script=\'"+t.replace(/<\/?(br|p|pre)\s?\/?>/gi,"\n")+"\'/></div>"});
  st = st.replace(/insertASCIIMathCalculator/g,"<div class=\"ASCIIMathCalculator\"></div>");
  return st
}

function LMprocessNode(n, linebreaks, spanclassLM) {
  var frag,st;
  if (spanclassLM!=null) {
    frag = document.getElementsByTagName("span")
    for (var i=0;i<frag.length;i++)
      if (frag[i].className == "LM")
        LMprocessNodeR(frag[i],linebreaks);
  } else {
    try {
      st = n.innerHTML;
    } catch(err) {}
    var am = /amath|agraph/i.test(st);
    if ((st==null || st.indexOf("\$ ")!=-1 || st.indexOf("\$<")!=-1 || 
         st.indexOf("\\begin")!=-1 || am || st.slice(-1)=="$" ||
         st.indexOf("\$\n")!=-1)&& !/edit-content|HTMLArea|wikiedit/.test(st)){
      if (!avoidinnerHTML && translateLaTeXformatting) 
        st = simpleLaTeXformatting(st);
      if (st!=null && am && !avoidinnerHTML) {
//alert(st)
        st = st.replace(/<sup>(.*?)<\/sup>(\s|(\S))/gi,"^{$1} $3");
//        st = st.replace(/<\/?font.*?>/gi,""); // do this only in amath...end
        st = st.replace(/(Proof:)/g,"<i>$1</i>");
        st = st.replace(/QED/g,"&#x25A1;");
        st = st.replace(/(\\?end{?a?math}?)/ig,"<span></span>$1");
        st = st.replace(/(\bamath|\\begin{a?math})/ig,"<span></span>$1");
        st = st.replace(/([>\n])(Theorem|Lemma|Proposition|Corollary|Definition|Example|Remark|Problem|Exercise|Conjecture|Solution)(:|\W\W?(\w|\.)*?\W?:)/g,"$1<b>$2$3</b>");
      }
      st = st.replace(/%7E/g,"~");
      if (!avoidinnerHTML) n.innerHTML = st;
      LMprocessNodeR(n,linebreaks);
    }
  }
  if (isIE) { //needed to match size and font of formula to surrounding text
    frag = document.getElementsByTagName('math');
    for (var i=0;i<frag.length;i++) frag[i].update()
  }
}

var LMbody;
var LMnoMathML = false, LMtranslated = false;

function LMtranslate(spanclassLM) {
  if (!LMtranslated) { // run this only once
    LMtranslated = true;
    LMinitSymbols();
    LMbody = document.getElementsByTagName("body")[0];
    var processN = document.getElementById(AMdocumentId);
//alert(processN)
    LMprocessNode((processN!=null?processN:LMbody), false, spanclassLM);
  }
}

if (isIE) { // avoid adding MathPlayer info explicitly to each webpage
  document.write("<object id=\"mathplayer\"\
  classid=\"clsid:32F66A20-7614-11D4-BD11-00104BD3F987\"></object>");
  document.write("<?import namespace=\"m\" implementation=\"#mathplayer\"?>");
}

/* ASCIIsvg.js
==============
JavaScript routines to dynamically generate Scalable Vector Graphics
using a mathematical xy-coordinate system (y increases upwards) and
very intuitive JavaScript commands (no programming experience required).
ASCIIsvg.js is good for learning math and illustrating online math texts.
Works with Internet Explorer+Adobe SVGviewer and SVG enabled Mozilla/Firefox.

Ver 1.2.9 July 31, 2007 (c) Peter Jipsen http://www.chapman.edu/~jipsen
Latest version at http://math.chapman.edu/~jipsen/math/pub/ASCIIsvg.js
If you use it on a webpage, please send the URL to jipsen@chapman.edu

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or (at
your option) any later version.

This program is distributed in the hope that it will be useful, 
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser
General Public License (at http://www.gnu.org/license/lgpl.html) 
for more details.*/

// you can change these
var checkIfSVGavailable = true;
var notifyIfNoSVG = true;
var alertIfNoSVG = false;

// global defaults used if not specified by graph (you can change these)
var defaultwidth = 300; defaultheight = 200;   // in pixels
var defaultxmin = -5.5; defaultxmax = 5.5;     // in usercoords
var defaultborder = 0; border = defaultborder; // in pixel
var defaultstrokewidth = "1"; // default line width in pixel
var defaultstroke = "blue";   // default line color
var defaultstrokeopacity = 1; // transparent = 0, solid =1
var defaultstrokedasharray = null; // "10,10" gives 10px long dashes
var defaultfill = "none";        // default fill color
var defaultfillopacity = 1;      // transparent = 0, solid =1
var defaultfontstyle = "normal"; // default text shape normal|italic|inherit
var defaultfontfamily = "times"; // default font times|ariel|helvetica|...
var defaultfontsize = "16";      // default size (scaled automatically)
var defaultfontweight = "normal";// normal|bold|bolder|lighter|100|...|900
var defaultfontstroke = "none";  // default font outline color
var defaultfontfill = "none";    // default font color
var defaultmarker = "none";      // "dot" | "arrow" | "+" | "-" | "|"
var defaultendpoints = "";       // "c-d" where c is <|o|* and d is >|o|*

// global values used for all pictures (you can change these)
var showcoordinates = true;
var markerstrokewidth = "1";
var markerstroke = "black";
var markerfill = "yellow";
var markersize = 4;
var arrowfill = stroke;
var dotradius = 4;
var ticklength = 4;
var axesstroke = "black";
var gridstroke = "grey";
var backgroundstyle = "fill-opacity:0; fill:white";
var singlelettersitalic = true;

// internal variables (probably no need to change these)
var picturepos = null; // position of picture relative to top of HTML page
var xunitlength;       // in pixels, used to convert to user coordinates
var yunitlength;       // in pixels
var origin = [0,0];    // in pixels (default is bottom left corner)
var above = "above";   // shorthands (to avoid typing quotes)
var below = "below";
var left = "left";
var right = "right";
var aboveleft = "aboveleft";
var aboveright = "aboveright";
var belowleft = "belowleft";
var belowright = "belowright";
var xmin, xmax, ymin, ymax, xscl, yscl, 
    xgrid, ygrid, xtick, ytick, initialized;
var strokewidth, strokedasharray, stroke, fill, strokeopacity, fillopacity;
var fontstyle, fontfamily, fontsize, fontweight, fontstroke, fontfill;
var marker, endpoints, dynamic = {};
var picture, svgpicture, doc, width, height, a, b, c, d, i, n, p, t, x, y;
var isIE = document.createElementNS==null;

var cpi = "\u03C0", ctheta = "\u03B8";      // character for pi, theta
var log = function(x) { return ln(x)/ln(10) };
var pi = Math.PI, e = Math.E, ln = Math.log, sqrt = Math.sqrt;
var floor = Math.floor, ceil = Math.ceil, abs = Math.abs;
var sin = Math.sin, cos = Math.cos, tan = Math.tan;
var arcsin = Math.asin, arccos = Math.acos, arctan = Math.atan;
var sec = function(x) { return 1/Math.cos(x) };
var csc = function(x) { return 1/Math.sin(x) };
var cot = function(x) { return 1/Math.tan(x) };
var arcsec = function(x) { return arccos(1/x) };
var arccsc = function(x) { return arcsin(1/x) };
var arccot = function(x) { return arctan(1/x) };
var sinh = function(x) { return (Math.exp(x)-Math.exp(-x))/2 };
var cosh = function(x) { return (Math.exp(x)+Math.exp(-x))/2 };
var tanh = 
  function(x) { return (Math.exp(x)-Math.exp(-x))/(Math.exp(x)+Math.exp(-x)) };
var sech = function(x) { return 1/cosh(x) };
var csch = function(x) { return 1/sinh(x) };
var coth = function(x) { return 1/tanh(x) };
var arcsinh = function(x) { return ln(x+Math.sqrt(x*x+1)) };
var arccosh = function(x) { return ln(x+Math.sqrt(x*x-1)) };
var arctanh = function(x) { return ln((1+x)/(1-x))/2 };
var sech = function(x) { return 1/cosh(x) };
var csch = function(x) { return 1/sinh(x) };
var coth = function(x) { return 1/tanh(x) };
var arcsech = function(x) { return arccosh(1/x) };
var arccsch = function(x) { return arcsinh(1/x) };
var arccoth = function(x) { return arctanh(1/x) };
var sign = function(x) { return (x==0?0:(x<0?-1:1)) };

function factorial(x,n) { // Factorial function
  if (n==null) n=1;
  if (Math.abs(x-Math.round(x*1000000)/1000000)<1e-15)
    x = Math.round(x*1000000)/1000000;
  if (x-Math.floor(x)!=0) return NaN;
  for (var i=x-n; i>0; i-=n) x*=i;
  return (x<0?NaN:(x==0?1:x));
}

function C(x,k) {  // Binomial coefficient function
  var res=1;
  for (var i=0; i<k; i++) res*=(x-i)/(k-i);
  return res;
}

function chop(x,n) { // Truncate decimal number to n places after decimal point
  if (n==null) n=0;
  return Math.floor(x*Math.pow(10,n))/Math.pow(10,n);
}

function ran(a,b,n) { // Generate random number in [a,b] with n digits after .
  if (n==null) n=0;
  return chop((b+Math.pow(10,-n)-a)*Math.random()+a,n);
}

function myCreateElementXHTML(t) {
  if (isIE) return document.createElement(t);
  else return document.createElementNS("http://www.w3.org/1999/xhtml",t);
}

function myCreateElementSVG(t) {
  if (isIE) return doc.createElement(t);
  else return doc.createElementNS("http://www.w3.org/2000/svg",t);
}

function getElementsByClass(container, tagName, clsName){
  var list = new Array(0);
  var collection = container.getElementsByTagName(tagName);
  for(var i = 0; i < collection.length; i++)
    if(collection[i].className.slice(0,clsName.length)==clsName)
      list[list.length] = collection[i];
  return list;
}

function findPos(obj) { // top-left corner of obj on HTML page in pixel
  var curleft = curtop = 0;
  if (obj.offsetParent) {
    curleft = obj.offsetLeft
    curtop = obj.offsetTop
    while (obj = obj.offsetParent) {
      curleft += obj.offsetLeft
      curtop += obj.offsetTop
    }
  }
  return [curleft,curtop];
}

function isSVGavailable() {
  var nd = myCreateElementXHTML("");
  nd.appendChild(document.createTextNode(""));
  var an = myCreateElementXHTML("");
  an.appendChild(document.createTextNode(""));
  an.setAttribute("","");
  nd.appendChild(an);
  nd.appendChild(document.createTextNode(""));
  an = myCreateElementXHTML("");
  an.appendChild(document.createTextNode(""));
  an.setAttribute("","");
  nd.appendChild(an);
  nd.appendChild(document.createTextNode(""));
  an = myCreateElementXHTML("");
  an.appendChild(document.createTextNode(""));
  an.setAttribute("", "");
  nd.appendChild(an);
  if (navigator.appName.slice(0,8)=="Netscape") 
    if (window['SVGElement']) return null;
    else return nd;
  else if (navigator.appName.slice(0,9)=="Microsoft")
    try {
      var oSVG=eval("new ActiveXObject('Adobe.SVGCtl.3');");
        return null;
    } catch (e) {
        return nd;
    }
  else return nd;
}

function setText(st,id) { // add text to an existing node with given id
  var node = document.getElementById(id);
  if (node!=null)
    if (node.childNodes.length!=0) node.childNodes[0].nodeValue = st;
    else node.appendChild(document.createTextNode(st));
}

function getX(evt) { // return mouse x-coord in user coordinate system
  var svgroot = evt.target.parentNode;
  return (evt.clientX+(isIE?0:window.pageXOffset)-svgroot.getAttribute("left")-svgroot.getAttribute("ox"))/(svgroot.getAttribute("xunitlength")-0);
}

function getY(evt) { // return mouse y-coord in user coordinate system
  var svgroot = evt.target.parentNode;
  return (svgroot.getAttribute("height")-svgroot.getAttribute("oy")-(evt.clientY+(isIE?0:window.pageYOffset)-svgroot.getAttribute("top")))/(svgroot.getAttribute("yunitlength")-0);
}

function translateandeval(src) { //modify user input to JavaScript syntax
  var errstr;
  // replace plot(f(x),...) with plot("f(x)",...)  
  src = src.replace(/plot\(\x20*([^\"f\[][^\n\r;]+?)\,/g,"plot\(\"$1\",");
  src = src.replace(/plot\(\x20*([^\"f\[][^\n\r;]+)\)/g,"plot(\"$1\")");

  // replace (expr,expr) by [expr,expr] where expr has no (,) in it
  src = src.replace(/([=(,]\x20*)\(([-a-z0-9./+*]+?),([-a-z0-9./+*]+?)\)/g,"$1[$2,$3]");

  // insert * between digit and letter e.g. 2x --> 2*x
  src = src.replace(/([0-9])([a-zA-Z])/g,"$1*$2");
  src = src.replace(/\)([\(0-9a-zA-Z])/g,"\)*$1");

  try {
    with (Math) eval(src);          // here the svgpicture object is created
  } catch(err) {
    if (err!="wait") {
      if (typeof err=="object") 
        errstr = err.name+" "+err.message+" "+err.number+" "+err.description;
      else errstr = err;
      alert(errstr+"\n"+src)
    }
  }
}

function drawPictures() { // main routine; called after webpage has loaded
  var src, id, dsvg, nd, node, ht, index, cols, arr, i, node2;
  var pictures = document.getElementsByTagName("textarea");
  for (index = 0; index<pictures.length; index++)
    if (pictures[index].className=="ASCIIsvg"){
      pictures[index].style.display="none";  // hide the textarea
    }
  var ASbody = document.getElementsByTagName("body")[0];
  pictures = getElementsByClass(ASbody,"embed","ASCIIsvg");
  var len = pictures.length;
  if (checkIfSVGavailable) {
    nd = isSVGavailable();
    if (nd != null && notifyIfNoSVG && len>0)
      if (alertIfNoSVG)
        alert("To view the SVG pictures in Internet Explorer\n\
download the free Adobe SVGviewer from www.adobe.com/svg or\n\
use Firefox 2.0 or later");
      else {
        ASbody.insertBefore(nd,ASbody.childNodes[0]);
      }
  }
 if (nd == null) {
  for (index = 0; index < len; index++) {
   width = null; height = null; 
   xmin = null; xmax = null; ymin = null; ymax = null;
   xscl = null; xgrid = null; yscl = null; ygrid = null;
   initialized = false;
   picture = pictures[index];  // current picture object
   src = picture.getAttribute("script"); // get the ASCIIsvg code
   if (src==null) src = "";
   // insert "axes()" if not present  ******** experimental
   if (!/axes\b|initPicture/.test(src)) {
     var i = 0
     while (/((yscl|ymax|ymin|xscl|xmax|xmin|\bwidth|\bheight)\s*=\s*-?\d*(\d\.|\.\d|\d)\d*\s*;?)/.test(src.slice(i))) i++;
     src = (i==0?"axes(); "+src: src.slice(0,i)+src.slice(i).replace(/((scl|max|min|idth|eight)\s*=\s*-?\d*(\d\.|\.\d|\d)\d*\s*;?)/,"$1\naxes();"));
   }
   ht = picture.getAttribute("height");
   if (isIE) {
     picture.setAttribute("wmode","transparent");
//alert("*"+picture.getAttribute("src")+dsvglocation);
//adding d.svg dynamically greates problems in IE...
     if (picture.getAttribute("src")=="") picture.setAttribute("src",dsvglocation+"d.svg");
   }
   if (document.getElementById("picture"+(index+1)+"mml")==null) {
     picture.parentNode.style.position = "relative";
     node = myCreateElementXHTML("div");
     node.style.position = "absolute";
     node.style.top = "0px";
     node.style.left = "0px";
     node.setAttribute("id","picture"+(index+1)+"mml");
     picture.parentNode.insertBefore(node,picture.nextSibling);
   }
   if (ht==null) ht ="";
//   if (ht!="") defaultborder = 25;
   if (ht=="" || src=="") 
    if (document.getElementById("picture"+(index+1)+"input")==null) {
      node = myCreateElementXHTML("textarea");
      arr = src.split("\n");
      cols = 0;
      for (i=0;i<arr.length;i++) cols = Math.max(cols,arr[i].length);
      node.setAttribute("rows",Math.min(10,arr.length)+1);
      node.setAttribute("cols",Math.max(Math.min(60,cols),20)+5);
//      node.setAttribute("style","display:block");
      if (isIE) src = src.replace(/([^\r])\n/g,"$1\r");
      node.appendChild(document.createTextNode(src));
      if (src.indexOf("showcode()")==-1) node.style.display = "none";
      node.setAttribute("id","picture"+(index+1)+"input");
      picture.parentNode.insertBefore(node,picture.nextSibling);
      picture.parentNode.insertBefore(myCreateElementXHTML("br"),node);
      node2 = myCreateElementXHTML("button");
      node2.setAttribute("id","picture"+(index+1)+"button");
      if (isIE) node2.onclick = function() {updatePicture(this)};
      else node2.setAttribute("onclick","updatePicture(this)");
      node2.appendChild(document.createTextNode("Update"));
      if (src.indexOf("showcode()")==-1) node2.style.display = "none";
      picture.parentNode.insertBefore(node2,node);
      picture.parentNode.insertBefore(myCreateElementXHTML("br"),node);
    } else src = document.getElementById("picture"+(index+1)+"input").value;
    id = picture.getAttribute("id");
    dsvg = picture.getAttribute("src");
    if (id == null || id == "") {
      id = "picture"+(index+1);
      picture.setAttribute("id",id);
    }
    translateandeval(src)
  }
 }
}

function setdefaults() { //called before each graph is evaluated
  strokewidth = defaultstrokewidth;
  stroke = defaultstroke;
  strokeopacity = defaultstrokeopacity;
  strokedasharray = defaultstrokedasharray;
  fill = defaultfill;
  fillopacity = defaultfillopacity;
  fontstyle = defaultfontstyle;
  fontfamily = defaultfontfamily;
  fontsize = defaultfontsize;
  fontweight = defaultfontweight;
  fontstroke = defaultfontstroke;
  fontfill = defaultfontfill;
  marker = defaultmarker;
  endpoints = defaultendpoints;
}

function switchTo(id) { // used by dynamic code to select appropriate graph
  picture = document.getElementById(id);
  width = picture.getAttribute("width")-0;
  height = picture.getAttribute("height")-0;
  setdefaults();
  if ((picture.nodeName == "EMBED" || picture.nodeName == "embed") && isIE) {
    svgpicture = picture.getSVGDocument().getElementById("root");
    doc = picture.getSVGDocument();
  } else {
    svgpicture = picture;
    doc = document;
  }
  xunitlength = svgpicture.getAttribute("xunitlength")-0;
  yunitlength = svgpicture.getAttribute("yunitlength")-0;
  xmin = svgpicture.getAttribute("xmin")-0;
  xmax = svgpicture.getAttribute("xmax")-0;
  ymin = svgpicture.getAttribute("ymin")-0;
  ymax = svgpicture.getAttribute("ymax")-0;
  origin = [svgpicture.getAttribute("ox")-0,svgpicture.getAttribute("oy")-0];
}

function updatePicture(obj) {
  var node, src, id;
  if (typeof obj=="object") id = obj.id.slice(0,-6);
  else id = (typeof obj=="string"?obj:"picture"+(obj+1));
  src = document.getElementById(id+"input").value;
  xmin = null; xmax = null; ymin = null; ymax = null;
  xscl = null; xgrid = null; yscl = null; ygrid = null;
  initialized = false;
  picture = document.getElementById(id);
//  switchTo(id);
  translateandeval(src)
}

function changepicturesize(evt,factor) {
  var obj = evt.target;
  var name = obj.parentNode.getAttribute("name");
  var pic = document.getElementById(name);
  var src = document.getElementById(name+"input").value;
  src = src.replace(/width\s*=\s*\d+/,"width="+(factor*(pic.getAttribute("width")-0)));
  src = src.replace(/height\s*=\s*\d+/,"height="+(factor*(pic.getAttribute("height")-0)));
  document.getElementById(name+"input").value = src;
//alert(getKey(evt.keycode))
  updatePicture(name);
}

var sinceFirstClick = 0; // ondblclick simulation from 
var dblClkTimer;         // http://www.enja.org/david/?cat=13 Thanks!
function timer() {
  if(sinceFirstClick<60) {
    sinceFirstClick++;
    setTimeout("timer()",10);
  } else {
    clearTimeout(dblClkTimer);
    dblClkTimer = "";
  }
}
function mClick(evt) {
  if(sinceFirstClick!=0) {
    if(sinceFirstClick <= 40) {
      if (evt.shiftKey) changepicturesize(evt,2);
      else if (evt.altKey) changepicturesize(evt,.5);
      else showHideCode(evt);             // do this on dblclick
      clearTimeout(dblClkTimer);
      dblClkTimer = "";
    } else {
      clearTimeout(dblClkTimer);
      sinceFirstClick = 0;
      dblClkTimer = setTimeout("timer()",10);
    }	      
  } else {
    sinceFirstClick = 0;
    dblClkTimer = setTimeout("timer()",10);
  }
}

function showHideCode(evt) { // called by onclick event
//  if (evt.getDetail()==2) {//getDetail unfortunately not in Firefox
  var obj=evt.target;
  var name = obj.parentNode.getAttribute("name");
  var node = document.getElementById(name+"input");
  node.style.display = (node.style.display == "none"?"":"none");
  var node = document.getElementById(name+"button");
  node.style.display = (node.style.display == "none"?"":"none");
//  }
}

function showcode() {} // do nothing

function setBorder(x) { border = x } //deprecate

function initPicture(x_min,x_max,y_min,y_max) { // set up the graph
// usually called by axes() or noaxes(), but can be used directly
 if (!initialized) {
  setdefaults();
  initialized = true;
  if (x_min!=null) xmin = x_min;
  if (x_max!=null) xmax = x_max;
  if (y_min!=null) ymin = y_min;
  if (y_max!=null) ymax = y_max;
  if (xmin==null) xmin = defaultxmin;
  if (xmax==null) xmax = defaultxmax;
 if (typeof xmin != "number" || typeof xmax != "number" || xmin >= xmax) 
   alert("Picture requires at least two numbers: xmin < xmax");
 else if (y_max != null && (typeof y_min != "number" || 
          typeof y_max != "number" || y_min >= y_max))
   alert("initPicture(xmin,xmax,ymin,ymax) requires numbers ymin < ymax");
 else {
  if (width==null) {
    width = picture.getAttribute("width");
    if (width==null || width=="") width=defaultwidth;
  }
  picture.setAttribute("width",width);
  if (height==null) { 
    height = picture.getAttribute("height");
    if (height==null || height=="") height=defaultheight;
  }
  picture.setAttribute("height",height);
  xunitlength = (width-2*border)/(xmax-xmin);
  yunitlength = xunitlength;
//alert(xmin+" "+xmax+" "+ymin+" "+ymax)
  if (ymin==null) {
    origin = [-xmin*xunitlength+border,height/2];
    ymin = -(height-2*border)/(2*yunitlength);
    ymax = -ymin;
  } else {
    if (ymax!=null) yunitlength = (height-2*border)/(ymax-ymin);
    else ymax = (height-2*border)/yunitlength + ymin;
    origin = [-xmin*xunitlength+border,-ymin*yunitlength+border];
  }
  if (isIE) {
    if (picture.FULLSCREEN==undefined) {
      setTimeout('drawPictures()',50);
      throw "wait";
    }
    svgpicture = picture.getSVGDocument().getElementById("root");
    if (svgpicture==null) {
      setTimeout('drawPictures()',50);
      throw "wait";
    }
    svgpicture = picture.getSVGDocument().getElementById("root");
    while (svgpicture.childNodes.length>0) 
      svgpicture.removeChild(svgpicture.lastChild); 
    svgpicture.setAttribute("width",width);
    svgpicture.setAttribute("height",height);
    svgpicture.setAttribute("name",picture.getAttribute("id"));
    doc = picture.getSVGDocument();
    var nd = document.getElementById(picture.getAttribute("id")+"mml");
    if (nd!=null) // clear out MathML layer
      while (nd.childNodes.length>0) nd.removeChild(nd.lastChild); 
  } else {
    var qnode = document.createElementNS("http://www.w3.org/2000/svg","svg");
    qnode.setAttribute("id",picture.getAttribute("id"));
    qnode.setAttribute("name",picture.getAttribute("id"));
    qnode.setAttribute("style","display:inline");
    qnode.setAttribute("width",picture.getAttribute("width"));
    qnode.setAttribute("height",picture.getAttribute("height"));
    picturepos = findPos(picture);
    qnode.setAttribute("left",picturepos[0]);
    qnode.setAttribute("top",picturepos[1]);
//      qnode.setAttribute("xmlns:xlink","http://www.w3.org/1999/xlink");
    if (picture.parentNode!=null) {
      picture.parentNode.replaceChild(qnode,picture);
    } else {
      svgpicture.parentNode.replaceChild(qnode,svgpicture);
    }
    svgpicture = qnode;
    doc = document;
  }
  svgpicture.setAttribute("xunitlength",xunitlength);
  svgpicture.setAttribute("yunitlength",yunitlength);
  svgpicture.setAttribute("xmin",xmin);
  svgpicture.setAttribute("xmax",xmax);
  svgpicture.setAttribute("ymin",ymin);
  svgpicture.setAttribute("ymax",ymax);
  svgpicture.setAttribute("ox",origin[0]);
  svgpicture.setAttribute("oy",origin[1]);
  var node = myCreateElementSVG("rect");
  node.setAttribute("x","0");
  node.setAttribute("y","0");
  node.setAttribute("width",width);
  node.setAttribute("height",height);
  node.setAttribute("style",backgroundstyle);
  svgpicture.appendChild(node);
  svgpicture.setAttribute("onmousemove","displayCoord(evt)");
  svgpicture.setAttribute("onmouseout","removeCoord(evt)");
  svgpicture.setAttribute("onclick","mClick(evt)");
  node = myCreateElementSVG("text");
  node.appendChild(doc.createTextNode(" "));
  svgpicture.appendChild(node);
  border = defaultborder;
 }
 }
}

//////////////////////////user graphics commands start/////////////////////////

function line(p,q,id,endpts) { // segment connecting points p,q (coordinates in units)
  var node;
  if (id!=null) node = doc.getElementById(id);
  if (node==null) {
    node = myCreateElementSVG("path");
    node.setAttribute("id", id);
    svgpicture.appendChild(node);
  }
  node.setAttribute("d","M"+(p[0]*xunitlength+origin[0])+","+
    (height-p[1]*yunitlength-origin[1])+" "+
    (q[0]*xunitlength+origin[0])+","+(height-q[1]*yunitlength-origin[1]));
  node.setAttribute("stroke-width", strokewidth);
  if (strokedasharray!=null) 
    node.setAttribute("stroke-dasharray", strokedasharray);
  node.setAttribute("stroke", stroke);
  node.setAttribute("fill", fill);
  node.setAttribute("stroke-opacity", strokeopacity);
  node.setAttribute("fill-opacity", fillopacity);
  if (marker=="dot" || marker=="arrowdot") {
    ASdot(p,markersize,markerstroke,markerfill);
    if (marker=="arrowdot") arrowhead(p,q);
    ASdot(q,markersize,markerstroke,markerfill);
  } else if (marker=="arrow") arrowhead(p,q);
  if (endpts==null && endpoints!="") endpts = endpoints;
  if (endpts!=null) {
    if (endpts.indexOf("<-") != -1) arrowhead(q,p);
    if (endpts.indexOf("o-") != -1) dot(p, "open");
    if (endpts.indexOf("*-") != -1) dot(p, "closed");
    if (endpts.indexOf("->") != -1) arrowhead(p,q);
    if (endpts.indexOf("-o") != -1) dot(q, "open");
    if (endpts.indexOf("-*") != -1) dot(q, "closed");
  }
}

function path(plist,id,c,endpts) {
  if (c==null) c="";
  var node, st, i;
  if (id!=null) node = doc.getElementById(id);
  if (node==null) {
    node = myCreateElementSVG("path");
    node.setAttribute("id", id);
    svgpicture.appendChild(node);
  }
  if (typeof plist == "string") st = plist;
  else {
    st = "M";
    st += (plist[0][0]*xunitlength+origin[0])+","+
          (height-plist[0][1]*yunitlength-origin[1])+" "+c;
    for (i=1; i<plist.length; i++)
      st += (plist[i][0]*xunitlength+origin[0])+","+
            (height-plist[i][1]*yunitlength-origin[1])+" ";
  }
  node.setAttribute("d", st);
  node.setAttribute("stroke-width", strokewidth);
  if (strokedasharray!=null) 
    node.setAttribute("stroke-dasharray", strokedasharray);
  node.setAttribute("stroke", stroke);
  node.setAttribute("fill", fill);
  node.setAttribute("stroke-opacity", strokeopacity);
  node.setAttribute("fill-opacity", fillopacity);
  if (marker=="dot" || marker=="arrowdot")
    for (i=0; i<plist.length; i++)
      if (c!="C" && c!="T" || i!=1 && i!=2)
        ASdot(plist[i],markersize,markerstroke,markerfill);
  if (endpts==null && endpoints!="") endpts = endpoints;
  if (endpts!=null) {
    if (endpts.indexOf("<-") != -1) arrowhead(plist[1],plist[0]);
    if (endpts.indexOf("o-") != -1) dot(plist[0], "open");
    if (endpts.indexOf("*-") != -1) dot(plist[0], "closed");
    if (endpts.indexOf("->") != -1) arrowhead(plist[plist.length-2],plist[plist.length-1]);
    if (endpts.indexOf("-o") != -1) dot(plist[plist.length-1], "open");
    if (endpts.indexOf("-*") != -1) dot(plist[plist.length-1], "closed");
  }
}

function curve(plist,id,endpts) {
  path(plist,id,"T",endpts);
}

function vector(p,q,id) {
  line(p,q,id,"","->");
}

function circle(center,radius,id) { // coordinates in units
  var node;
  if (id!=null) node = doc.getElementById(id);
  if (node==null) {
    node = myCreateElementSVG("circle");
    node.setAttribute("id", id);
    svgpicture.appendChild(node);
  }
  node.setAttribute("cx",center[0]*xunitlength+origin[0]);
  node.setAttribute("cy",height-center[1]*yunitlength-origin[1]);
  node.setAttribute("r",radius*xunitlength);
  node.setAttribute("stroke-width", strokewidth);
  node.setAttribute("stroke", stroke);
  node.setAttribute("fill", fill);
  node.setAttribute("stroke-opacity", strokeopacity);
  node.setAttribute("fill-opacity", fillopacity);
}

function loop(p,d,id) { 
// d is a direction vector e.g. [1,0] means loop starts in that direction
  if (d==null) d=[1,0];
  path([p,[p[0]+d[0],p[1]+d[1]],[p[0]-d[1],p[1]+d[0]],p],id,"C");
  if (marker=="arrow" || marker=="arrowdot") 
    arrowhead([p[0]+Math.cos(1.4)*d[0]-Math.sin(1.4)*d[1],
               p[1]+Math.sin(1.4)*d[0]+Math.cos(1.4)*d[1]],p);
}

function arc(start,end,radius,id) { // coordinates in units
  var node, v;
//alert([fill, stroke, origin, xunitlength, yunitlength, height])
  if (id!=null) node = doc.getElementById(id);
  if (radius==null) {
    v=[end[0]-start[0],end[1]-start[1]];
    radius = Math.sqrt(v[0]*v[0]+v[1]*v[1]);
  }
  if (node==null) {
    node = myCreateElementSVG("path");
    node.setAttribute("id", id);
    svgpicture.appendChild(node);
  }
  node.setAttribute("d","M"+(start[0]*xunitlength+origin[0])+","+
    (height-start[1]*yunitlength-origin[1])+" A"+radius*xunitlength+","+
     radius*yunitlength+" 0 0,0 "+(end[0]*xunitlength+origin[0])+","+
    (height-end[1]*yunitlength-origin[1]));
  node.setAttribute("stroke-width", strokewidth);
  node.setAttribute("stroke", stroke);
  node.setAttribute("fill", fill);
  node.setAttribute("stroke-opacity", strokeopacity);
  node.setAttribute("fill-opacity", fillopacity);
  if (marker=="arrow" || marker=="arrowdot") {
    u = [(end[1]-start[1])/4,(start[0]-end[0])/4];
    v = [(end[0]-start[0])/2,(end[1]-start[1])/2];
//alert([u,v])
    v = [start[0]+v[0]+u[0],start[1]+v[1]+u[1]];
  } else v=[start[0],start[1]];
  if (marker=="dot" || marker=="arrowdot") {
    ASdot(start,markersize,markerstroke,markerfill);
    if (marker=="arrowdot") arrowhead(v,end);
    ASdot(end,markersize,markerstroke,markerfill);
  } else if (marker=="arrow") arrowhead(v,end);
}

function sector(center,start,end,id) { // center,start,end should be isoceles
  var rx = start[0]-center[0], ry = start[1]-center[1];
  arc(start,end,Math.sqrt(rx*rx+ry*ry),id+"arc");
  path([end,center,start],id+"path");
}

function ellipse(center,rx,ry,id) { // coordinates in units
  var node;
  if (id!=null) node = doc.getElementById(id);
  if (node==null) {
    node = myCreateElementSVG("ellipse");
    node.setAttribute("id", id);
    svgpicture.appendChild(node);
  }
  node.setAttribute("cx",center[0]*xunitlength+origin[0]);
  node.setAttribute("cy",height-center[1]*yunitlength-origin[1]);
  node.setAttribute("rx",rx*xunitlength);
  node.setAttribute("ry",ry*yunitlength);
  node.setAttribute("stroke-width", strokewidth);
  node.setAttribute("stroke", stroke);
  node.setAttribute("fill", fill);
  node.setAttribute("stroke-opacity", strokeopacity);
  node.setAttribute("fill-opacity", fillopacity);
}

function triangle(p,q,r,id) {
  path([p,q,r,p],id)
}

function rect(p,q,id,rx,ry) { // opposite corners in units, rounded by radii
  var node;
  if (id!=null) node = doc.getElementById(id);
  if (node==null) {
    node = myCreateElementSVG("rect");
    node.setAttribute("id", id);
    svgpicture.appendChild(node);
  }
  node.setAttribute("x",p[0]*xunitlength+origin[0]);
  node.setAttribute("y",height-q[1]*yunitlength-origin[1]);
  node.setAttribute("width",(q[0]-p[0])*xunitlength);
  node.setAttribute("height",(q[1]-p[1])*yunitlength);
  if (rx!=null) node.setAttribute("rx",rx*xunitlength);
  if (ry!=null) node.setAttribute("ry",ry*yunitlength);
  node.setAttribute("stroke-width", strokewidth);
  node.setAttribute("stroke", stroke);
  node.setAttribute("fill", fill);
  node.setAttribute("stroke-opacity", strokeopacity);
  node.setAttribute("fill-opacity", fillopacity);
}

function text(p,st,pos,id,fontsty) {
  var dnode, node, dx = 0, dy = fontsize/3;
  if (/(`|\$)/.test(st)) {  // layer for ASCIIMathML and LaTeXMathML
    dnode = document.getElementById(svgpicture.getAttribute("name")+"mml");
    if (dnode!=null) {
      if (id!=null) node = document.getElementById(id);
      if (node==null) {
//alert(dnode.childNodes.length)
        node = myCreateElementXHTML("div");
        node.setAttribute("id", id);
        node.style.position = "absolute";
        dnode.appendChild(node);
      }
      while (node.childNodes.length>0) node.removeChild(node.lastChild); 
      node.appendChild(document.createTextNode(st));
//      node.lastChild.nodeValue = st;
      node.style.left = ""+(p[0]*xunitlength+origin[0])+"px";
      node.style.top = ""+(height-p[1]*yunitlength-origin[1])+"px";
      if (/`/.test(st)) AMprocessNode(node); else LMprocessNode(node);
      dx = -node.offsetWidth/2;
      dy = -node.offsetHeight/2;
      if (pos!=null) {
        if (/above/.test(pos)) dy = -node.offsetHeight;
        if (/below/.test(pos)) dy = 0;
        if (/right/.test(pos)) dx = 0;
        if ( /left/.test(pos)) dx = -node.offsetWidth;
      }
      node.style.left = ""+(p[0]*xunitlength+origin[0]+dx)+"px";
      node.style.top = ""+(height-p[1]*yunitlength-origin[1]+dy)+"px";
    }
    return p;
  }
  var textanchor = "middle";  // regular text goes into SVG
  if (pos!=null) {
    if (/above/.test(pos)) dy = -fontsize/2;
    if (/below/.test(pos)) dy = fontsize-0;
    if (/right/.test(pos)) {textanchor = "start"; dx = fontsize/4;}
    if ( /left/.test(pos)) {textanchor = "end";  dx = -fontsize/4;}
  }
  if (id!=null) node = doc.getElementById(id);
  if (node==null) {
    node = myCreateElementSVG("text");
    node.setAttribute("id", id);
    svgpicture.appendChild(node);
    node.appendChild(doc.createTextNode(st));
  }
  while (node.childNodes.length>1) node.removeChild(node.lastChild); 
//  node.appendChild(document.createTextNode("\xA0"+st+"\xA0"));
//alert("here");
  node.lastChild.nodeValue = "\xA0"+st+"\xA0";
  node.setAttribute("x",p[0]*xunitlength+origin[0]+dx);
  node.setAttribute("y",height-p[1]*yunitlength-origin[1]+dy);
  node.setAttribute("font-style",(fontsty!=null?fontsty:
    (st.search(/^[a-zA-Z]$/)!=-1?"italic":fontstyle)));
  node.setAttribute("font-family",fontfamily);
  node.setAttribute("font-size",fontsize);
  node.setAttribute("font-weight",fontweight);
  node.setAttribute("text-anchor",textanchor);
  if (fontstroke!="none") node.setAttribute("stroke",fontstroke);
  if (fontfill!="none") node.setAttribute("fill",fontfill);
  return p;
}

function mtext(p,st,pos,fontsty) { // method for updating text on an svg
// "this" is the text object or the svgpicture object
  var textanchor = "middle";
  var dx = 0; var dy = fontsize/3;
  if (pos!=null) {
    if (pos.slice(0,5)=="above") dy = -fontsize/2;
    if (pos.slice(0,5)=="below") dy = fontsize-0;
    if (pos.slice(0,5)=="right" || pos.slice(5,10)=="right") {
      textanchor = "start";
      dx = fontsize/2;
    }
    if (pos.slice(0,4)=="left" || pos.slice(5,9)=="left") {
      textanchor = "end";
      dx = -fontsize/2;
    }
  }
  var node = this;
  if (this.nodeName=="svg") {
    node = myCreateElementSVG("text");
    this.appendChild(node);
    node.appendChild(doc.createTextNode(st));
  }
  node.lastChild.nodeValue = st;
  node.setAttribute("x",p[0]+dx);
  node.setAttribute("y",p[1]+dy);
  node.setAttribute("font-style",(fontsty!=null?fontsty:fontstyle));
  node.setAttribute("font-family",fontfamily);
  node.setAttribute("font-size",fontsize);
  node.setAttribute("font-weight",fontweight);
  node.setAttribute("text-anchor",textanchor);
  if (fontstroke!="none") node.setAttribute("stroke",fontstroke);
  if (fontfill!="none") node.setAttribute("fill",fontfill);
}

function image(imgurl,p,w,h,id) { // not working yet
  var node;
  if (id!=null) node = doc.getElementById(id);
  if (node==null) {
    node = myCreateElementSVG("image");
    node.setAttribute("id", id);
    svgpicture.appendChild(node);
  }
  node.setAttribute("x",p[0]*xunitlength+origin[0]);
  node.setAttribute("y",height-p[1]*yunitlength-origin[1]);
  node.setAttribute("width",w);
  node.setAttribute("height",h);
  node.setAttribute("xlink:href", imgurl);
}

function ASdot(center,radius,s,f) { // coordinates in units, radius in pixel
  if (s==null) s = stroke; if (f==null) f = fill;
  var node = myCreateElementSVG("circle");
  node.setAttribute("cx",center[0]*xunitlength+origin[0]);
  node.setAttribute("cy",height-center[1]*yunitlength-origin[1]);
  node.setAttribute("r",radius);
  node.setAttribute("stroke-width", strokewidth);
  node.setAttribute("stroke", s);
  node.setAttribute("fill", f);
  svgpicture.appendChild(node);
}

function dot(center, typ, label, pos, id) {
  var node;
  var cx = center[0]*xunitlength+origin[0];
  var cy = height-center[1]*yunitlength-origin[1];
  if (id!=null) node = doc.getElementById(id);
  if (typ=="+" || typ=="-" || typ=="|") {
    if (node==null) {
      node = myCreateElementSVG("path");
      node.setAttribute("id", id);
      svgpicture.appendChild(node);
    }
    if (typ=="+") {
      node.setAttribute("d",
        " M "+(cx-ticklength)+" "+cy+" L "+(cx+ticklength)+" "+cy+
        " M "+cx+" "+(cy-ticklength)+" L "+cx+" "+(cy+ticklength));
      node.setAttribute("stroke-width", .5);
      node.setAttribute("stroke", axesstroke);
    } else {
      if (typ=="-") node.setAttribute("d",
        " M "+(cx-ticklength)+" "+cy+" L "+(cx+ticklength)+" "+cy);
      else node.setAttribute("d",
        " M "+cx+" "+(cy-ticklength)+" L "+cx+" "+(cy+ticklength));
      node.setAttribute("stroke-width", strokewidth);
      node.setAttribute("stroke", stroke);
    }
  } else {
    if (node==null) {
      node = myCreateElementSVG("circle");
      node.setAttribute("id", id);
      svgpicture.appendChild(node);
    }
    node.setAttribute("cx",cx);
    node.setAttribute("cy",cy);
    node.setAttribute("r",dotradius);
    node.setAttribute("stroke-width", strokewidth);
    node.setAttribute("stroke", stroke);
    node.setAttribute("fill", (typ=="open"?"white":
                              (typ=="closed"?stroke:markerfill)));
  }
  if (label!=null) 
    text(center,label,(pos==null?"below":pos),(id==null?id:id+"label"))
}

point = dot; //alternative name

function arrowhead(p,q) { // draw arrowhead at q (in units) add size param
  var up;
  var v = [p[0]*xunitlength+origin[0],height-p[1]*yunitlength-origin[1]];
  var w = [q[0]*xunitlength+origin[0],height-q[1]*yunitlength-origin[1]];
  var u = [w[0]-v[0],w[1]-v[1]];
  var d = Math.sqrt(u[0]*u[0]+u[1]*u[1]);
  if (d > 0.00000001) {
    u = [u[0]/d, u[1]/d];
    up = [-u[1],u[0]];
    var node = myCreateElementSVG("path");
    node.setAttribute("d","M "+(w[0]-15*u[0]-4*up[0])+" "+
      (w[1]-15*u[1]-4*up[1])+" L "+(w[0]-3*u[0])+" "+(w[1]-3*u[1])+" L "+
      (w[0]-15*u[0]+4*up[0])+" "+(w[1]-15*u[1]+4*up[1])+" z");
    node.setAttribute("stroke-width", markerstrokewidth);
    node.setAttribute("stroke", stroke); /*was markerstroke*/
    node.setAttribute("fill", stroke); /*was arrowfill*/
    node.setAttribute("stroke-opacity", strokeopacity);
    node.setAttribute("fill-opacity", fillopacity);
    svgpicture.appendChild(node);    
  }
}

function chopZ(st) {
  var k = st.indexOf(".");
  if (k==-1) return st;
  for (var i=st.length-1; i>k && st.charAt(i)=="0"; i--);
  if (i==k) i--;
  return st.slice(0,i+1);
}

function grid(dx,dy) { // for backward compatibility
  axes(dx,dy,null,dx,dy)
}

function noaxes() {
  if (!initialized) initPicture();
}

function axes(dx,dy,labels,gdx,gdy) {
//xscl=x is equivalent to xtick=x; xgrid=x; labels=true;
  var x, y, ldx, ldy, lx, ly, lxp, lyp, pnode, st;
  if (!initialized) initPicture();
  if (typeof dx=="string") { labels = dx; dx = null; }
  if (typeof dy=="string") { gdx = dy; dy = null; }
  if (xscl!=null) {dx = xscl; gdx = xscl; labels = dx}
  if (yscl!=null) {dy = yscl; gdy = yscl}
  if (xtick!=null) {dx = xtick}
  if (ytick!=null) {dy = ytick}
  dx = (dx==null?xunitlength:dx*xunitlength);
  dy = (dy==null?dx:dy*yunitlength);
  fontsize = Math.min(dx/2,dy/2,16); //alert(fontsize)
  ticklength = fontsize/4;
  if (xgrid!=null) gdx = xgrid;
  if (ygrid!=null) gdy = ygrid;
  if (gdx!=null) {
    gdx = (typeof gdx=="string"?dx:gdx*xunitlength);
    gdy = (gdy==null?dy:gdy*yunitlength);
    pnode = myCreateElementSVG("path");
    st="";
    for (x = origin[0]; x<width; x = x+gdx)
      st += " M"+x+",0"+" "+x+","+height;
    for (x = origin[0]-gdx; x>0; x = x-gdx)
      st += " M"+x+",0"+" "+x+","+height;
    for (y = height-origin[1]; y<height; y = y+gdy)
      st += " M0,"+y+" "+width+","+y;
    for (y = height-origin[1]-gdy; y>0; y = y-gdy)
      st += " M0,"+y+" "+width+","+y;
    pnode.setAttribute("d",st);
    pnode.setAttribute("stroke-width", .5);
    pnode.setAttribute("stroke", gridstroke);
    pnode.setAttribute("fill", fill);
    svgpicture.appendChild(pnode);
  }
  pnode = myCreateElementSVG("path");
  st="M0,"+(height-origin[1])+" "+width+","+
    (height-origin[1])+" M"+origin[0]+",0 "+origin[0]+","+height;
  for (x = origin[0]+dx; x<width; x = x+dx)
    st += " M"+x+","+(height-origin[1]+ticklength)+" "+x+","+
           (height-origin[1]-ticklength);
  for (x = origin[0]-dx; x>0; x = x-dx)
    st += " M"+x+","+(height-origin[1]+ticklength)+" "+x+","+
           (height-origin[1]-ticklength);
  for (y = height-origin[1]+dy; y<height; y = y+dy)
    st += " M"+(origin[0]+ticklength)+","+y+" "+(origin[0]-ticklength)+","+y;
  for (y = height-origin[1]-dy; y>0; y = y-dy)
    st += " M"+(origin[0]+ticklength)+","+y+" "+(origin[0]-ticklength)+","+y;
  if (labels!=null) with (Math) {
    ldx = dx/xunitlength;
    ldy = dy/yunitlength;
    lx = (xmin>0 || xmax<0?xmin:0);
    ly = (ymin>0 || ymax<0?ymin:0);
    lxp = (ly==0?"below":"above");
    lyp = (lx==0?"left":"right");
    var ddx = floor(1.1-log(ldx)/log(10))+1;
    var ddy = floor(1.1-log(ldy)/log(10))+1;
    for (x = ldx; x<=xmax; x = x+ldx)
      text([x,ly],chopZ(x.toFixed(ddx)),lxp);
    for (x = -ldx; xmin<=x; x = x-ldx)
      text([x,ly],chopZ(x.toFixed(ddx)),lxp);
    for (y = ldy; y<=ymax; y = y+ldy)
      text([lx,y],chopZ(y.toFixed(ddy)),lyp);
    for (y = -ldy; ymin<=y; y = y-ldy)
      text([lx,y],chopZ(y.toFixed(ddy)),lyp);
  }
  fontsize = defaultfontsize;
  pnode.setAttribute("d",st);
  pnode.setAttribute("stroke-width", .5);
  pnode.setAttribute("stroke", axesstroke);
  pnode.setAttribute("fill", fill);
  pnode.setAttribute("stroke-opacity", strokeopacity);
  pnode.setAttribute("fill-opacity", fillopacity);
  svgpicture.appendChild(pnode);
}

function mathjs(st) {
  //translate a math formula to js function notation
  // a^b --> pow(a,b)
  // na --> n*a
  // (...)d --> (...)*d
  // n! --> factorial(n)
  // sin^-1 --> arcsin etc.
  //while ^ in string, find term on left and right
  //slice and concat new formula string
  st = st.replace(/\s/g,"");
  if (st.indexOf("^-1")!=-1) {
    st = st.replace(/sin\^-1/g,"arcsin");
    st = st.replace(/cos\^-1/g,"arccos");
    st = st.replace(/tan\^-1/g,"arctan");
    st = st.replace(/sec\^-1/g,"arcsec");
    st = st.replace(/csc\^-1/g,"arccsc");
    st = st.replace(/cot\^-1/g,"arccot");
    st = st.replace(/sinh\^-1/g,"arcsinh");
    st = st.replace(/cosh\^-1/g,"arccosh");
    st = st.replace(/tanh\^-1/g,"arctanh");
    st = st.replace(/sech\^-1/g,"arcsech");
    st = st.replace(/csch\^-1/g,"arccsch");
    st = st.replace(/coth\^-1/g,"arccoth");
  }
  st = st.replace(/^e$/g,"(Math.E)");
  st = st.replace(/^e([^a-zA-Z])/g,"(Math.E)$1");
  st = st.replace(/([^a-zA-Z])e/g,"$1(Math.E)");
//  st = st.replace(/([^a-zA-Z])e([^a-zA-Z])/g,"$1(Math.E)$2");
  st = st.replace(/([0-9])([\(a-zA-Z])/g,"$1*$2");
  st = st.replace(/\)([\(0-9a-zA-Z])/g,"\)*$1");
  var i,j,k, ch, nested;
  while ((i=st.indexOf("^"))!=-1) {
    //find left argument
    if (i==0) return "Error: missing argument";
    j = i-1;
    ch = st.charAt(j);
    if (ch>="0" && ch<="9") {// look for (decimal) number
      j--;
      while (j>=0 && (ch=st.charAt(j))>="0" && ch<="9") j--;
      if (ch==".") {
        j--;
        while (j>=0 && (ch=st.charAt(j))>="0" && ch<="9") j--;
      }
    } else if (ch==")") {// look for matching opening bracket and function name
      nested = 1;
      j--;
      while (j>=0 && nested>0) {
        ch = st.charAt(j);
        if (ch=="(") nested--;
        else if (ch==")") nested++;
        j--;
      }
      while (j>=0 && (ch=st.charAt(j))>="a" && ch<="z" || ch>="A" && ch<="Z")
        j--;
    } else if (ch>="a" && ch<="z" || ch>="A" && ch<="Z") {// look for variable
      j--;
      while (j>=0 && (ch=st.charAt(j))>="a" && ch<="z" || ch>="A" && ch<="Z")
        j--;
    } else { 
      return "Error: incorrect syntax in "+st+" at position "+j;
    }
    //find right argument
    if (i==st.length-1) return "Error: missing argument";
    k = i+1;
    ch = st.charAt(k);
    if (ch>="0" && ch<="9" || ch=="-") {// look for signed (decimal) number
      k++;
      while (k<st.length && (ch=st.charAt(k))>="0" && ch<="9") k++;
      if (ch==".") {
        k++;
        while (k<st.length && (ch=st.charAt(k))>="0" && ch<="9") k++;
      }
    } else if (ch=="(") {// look for matching closing bracket and function name
      nested = 1;
      k++;
      while (k<st.length && nested>0) {
        ch = st.charAt(k);
        if (ch=="(") nested++;
        else if (ch==")") nested--;
        k++;
      }
    } else if (ch>="a" && ch<="z" || ch>="A" && ch<="Z") {// look for variable
      k++;
      while (k<st.length && (ch=st.charAt(k))>="a" && ch<="z" ||
               ch>="A" && ch<="Z") k++;
    } else { 
      return "Error: incorrect syntax in "+st+" at position "+k;
    }
    st = st.slice(0,j+1)+"Math.pow("+st.slice(j+1,i)+","+st.slice(i+1,k)+")"+
           st.slice(k);
  }
  while ((i=st.indexOf("!"))!=-1) {
    //find left argument
    if (i==0) return "Error: missing argument";
    j = i-1;
    ch = st.charAt(j);
    if (ch>="0" && ch<="9") {// look for (decimal) number
      j--;
      while (j>=0 && (ch=st.charAt(j))>="0" && ch<="9") j--;
      if (ch==".") {
        j--;
        while (j>=0 && (ch=st.charAt(j))>="0" && ch<="9") j--;
      }
    } else if (ch==")") {// look for matching opening bracket and function name
      nested = 1;
      j--;
      while (j>=0 && nested>0) {
        ch = st.charAt(j);
        if (ch=="(") nested--;
        else if (ch==")") nested++;
        j--;
      }
      while (j>=0 && (ch=st.charAt(j))>="a" && ch<="z" || ch>="A" && ch<="Z")
        j--;
    } else if (ch>="a" && ch<="z" || ch>="A" && ch<="Z") {// look for variable
      j--;
      while (j>=0 && (ch=st.charAt(j))>="a" && ch<="z" || ch>="A" && ch<="Z")
        j--;
    } else { 
      return "Error: incorrect syntax in "+st+" at position "+j;
    }
    st = st.slice(0,j+1)+"factorial("+st.slice(j+1,i)+")"+st.slice(i+1);
  }
  return st;
}

function plot(fun,x_min,x_max,points,id,endpts) {
  var pth = [];
  var f = function(x) { return x }, g = fun;
  var name = null;
  if (typeof fun=="string") 
    eval("g = function(x){ with(Math) return "+mathjs(fun)+" }");
  else if (typeof fun=="object") {
    eval("f = function(t){ with(Math) return "+mathjs(fun[0])+" }");
    eval("g = function(t){ with(Math) return "+mathjs(fun[1])+" }");
  }
  if (typeof x_min=="string") { name = x_min; x_min = xmin }
  else name = id;
  var min = (x_min==null?xmin:x_min);
  var max = (x_max==null?xmax:x_max);
  var inc = max-min-0.000001*(max-min);
  inc = (points==null?inc/200:inc/points);
  var gt;
//alert(typeof g(min))
  for (var t = min; t <= max; t += inc) {
    gt = g(t);
    if (!(isNaN(gt)||Math.abs(gt)=="Infinity")) pth[pth.length] = [f(t), gt];
  }
  path(pth,name,null,endpts);
  return p;
}

// make polar plot

// make Riemann sums

function slopefield(fun,dx,dy) {
  var g = fun;
  if (typeof fun=="string") 
    eval("g = function(x,y){ with(Math) return "+mathjs(fun)+" }");
  var gxy,x,y,u,v,dz;
  if (dx==null) dx=1;
  if (dy==null) dy=1;
  dz = Math.sqrt(dx*dx+dy*dy)/6;
  var x_min = Math.ceil(xmin/dx);
  var y_min = Math.ceil(ymin/dy);
  for (x = x_min; x <= xmax; x += dx)
    for (y = y_min; y <= ymax; y += dy) {
      gxy = g(x,y);
      if (!isNaN(gxy)) {
        if (Math.abs(gxy)=="Infinity") {u = 0; v = dz;}
        else {u = dz/Math.sqrt(1+gxy*gxy); v = gxy*u;}
        line([x-u,y-v],[x+u,y+v]);
      }
    }
}

///////////////////////user graphics commands end here/////////////////////////

function show_props(obj) {
  var result = "";
  for (var i=0; i< obj.childNodes.length; i++)
    result += obj.childNodes.item(i) + "\n";
  return result;
}

function displayCoord(evt) {
  if (showcoordinates) {
//alert(show_props(evt.target.parentNode))
    var svgroot = evt.target.parentNode;
    var nl = svgroot.childNodes;
    for (var i=0; i<nl.length && nl.item(i).nodeName!="text"; i++);
    var cnode = nl.item(i);
    cnode.mtext = mtext;
    cnode.mtext([svgroot.getAttribute("width")-0,svgroot.getAttribute("height")-0],"("+getX(evt).toFixed(2)+", "+getY(evt).toFixed(2)+")", "aboveleft", "");
  }
}

function removeCoord(evt) {
    var svgroot = evt.target.parentNode;
    var nl = svgroot.childNodes;
    for (var i=0; i<nl.length && nl.item(i).nodeName!="text"; i++);
    var cnode = nl.item(i);
    cnode.mtext = mtext;
    cnode.mtext([svgroot.getAttribute("width")-0,svgroot.getAttribute("height")-0],"", "aboveleft", "");
}

function initASCIIMathCalculators(li) {
  var i;
  for (i=0; i<li.length; i++) {
    li[i].innerHTML = calcstr;
    AMprocessNode(li[i]);
  }
  li = document.getElementsByTagName("textarea");
  var st;
  for (i=0; i<li.length; i++) {
    st = li[i].getAttribute("onkeyup");
    if (st!=null) eval(String(st).replace(/function anonymous\(\)/,""));
  }
}

function calculate(inputId,outputId) {
  var str = document.getElementById(inputId).value;
  var err = "";
  var ind = str.lastIndexOf("\n");
  if (ind==str.length-1) str = str.slice(0,ind);
  str = str.slice(str.lastIndexOf("\n")+1);
  try {
    var res = eval(mathjs(str));
  } catch(e) {
    err = "syntax incomplete";
  }
  if (!isNaN(res) && res!="Infinity") 
    str = "`"+str+" =` "+(Math.abs(res-Math.round(res*1000000)/1000000)<1e-15?Math.round(res*1000000)/1000000:res)+err; 
  else if (str!="") str = "`"+str+"` = undefined"; //debug:+mathjs(str);
  var outnode = document.getElementById(outputId);
  var n = outnode.childNodes.length;
  for (var i=0; i<n; i++)
    outnode.removeChild(outnode.firstChild);
  outnode.appendChild(document.createTextNode(str));
  AMprocessNode(outnode);
}

function append(st){
  document.getElementById('in').value+=st;
  calculate('in','out');
  document.getElementById('in').scrollTop = 1000;
  document.getElementById('in').focus();
}

function clearTextArea(){
  document.getElementById('in').value="";
  calculate('in','out');
  document.getElementById('in').focus();
}

var calcstr = "";
// GO1.1 Generic onload by Brothercake
// http://www.brothercake.com/
//onload function (replaces the onload="translate()" in the <body> tag)
function generic()
{
  if (translateOnLoad) {
    var nd = document.getElementById("processasciimathinmoodle");
    if (nd!=null) dsvglocation = nd.className;
    if (nd!=null || !checkforprocessasciimathinmoodle) {
      if (translateLaTeX) LMtranslate();
      if (translateASCIIMath) translate();
      if (translateASCIIsvg) drawPictures();
    }
    var li = getElementsByClass(document,"div","ASCIIMathCalculator");
    if (li.length>0) initASCIIMathCalculators(li);
  }
};
//setup onload function
if(typeof window.addEventListener != 'undefined')
{
  //.. gecko, safari, konqueror and standard
  window.addEventListener('load', generic, false);
}
else if(typeof document.addEventListener != 'undefined')
{
  //.. opera 7
  document.addEventListener('load', generic, false);
}
else if(typeof window.attachEvent != 'undefined')
{
  //.. win/ie
  window.attachEvent('onload', generic);
}
//** remove this condition to degrade older browsers
else
{
  //.. mac/ie5 and anything else that gets this far
  //if there's an existing onload function
  if(typeof window.onload == 'function')
  {
    //store it
    var existing = onload;
    //add new onload handler
    window.onload = function()
    {
      //call existing onload function
      existing();
      //call generic onload function
      generic();
    };
  }
  else
  {
    //setup onload function
    window.onload = generic;
  }
}