tests/plotter.html

   1 <!DOCTYPE html>
   2 <html>
   3   <head>
   4     <link rel="stylesheet" href="../css/dygraph.css">
   5     <title>dygraphs Equation Plotter</title>
   6     <!--
   7     For production (minified) code, use:
   8     <script type="text/javascript" src="dygraph-combined.js"></script>
   9     -->
  10     <script type="text/javascript" src="../dist/dygraph.js"></script>
  11
  12     <script type="text/javascript">
  13       function plot() {
  14         var eq = document.getElementById("eq").value;
  15         eval("fn = " + eq);
  16
  17         var graph = document.getElementById("graph_div");
  18         var width = parseInt(graph.style.width);
  19         var x1 = parseFloat(document.getElementById("x1").value);
  20         var x2 = parseFloat(document.getElementById("x2").value);
  21         var xs = 1.0 * (x2 - x1) / width;
  22
  23         var data = [];
  24         for (var i = 0; i < width; i++) {
  25           var x = x1 + i * xs;
  26           var y = fn(x);
  27           var row = [x];
  28           if (y.length > 0) {
  29             for (var j = 0; j < y.length; j++) {
  30               row.push(y[j]);
  31             }
  32           } else {
  33             row.push(y);
  34           }
  35           data.push(row);
  36         }
  37
  38         var labels = ['X'];
  39         if (data[0].length == 2) {
  40           labels.push('Y');
  41         } else {
  42           for (var i = 1; i < data[0].length; i++) {
  43             labels.push('Y' + (1 + i));
  44           }
  45         }
  46
  47         g = new Dygraph(graph, data, {
  48           labels: labels
  49         });
  50       }
  51
  52       function preset() {
  53         var sel = document.getElementById("presets").selectedIndex;
  54         var id = document.getElementById("presets").options[sel].id;
  55         var presets = {
  56           'id': [ -10, 10, 'function(x) {\n  return x;\n}' ],
  57           'sine': [ -10, 10, 'function(x) {\n  return Math.sin(x);\n}' ],
  58           'taylor': [ -3, 3, 'function(x) {\n  return [Math.cos(x), 1 - x*x/2 + x*x*x*x/24];\n}' ],
  59           'sawtooth': [-10, 10, 'function(x) {\n  var y = 0;\n  for (var i = 1; i < 20; i+=2) {\n    y += Math.sin(i * x)/i;\n  }\n  var final = 1 - 2*(Math.abs(Math.floor(x / Math.PI)) % 2);\n  return [4/Math.PI * y, final];\n}' ]
  60         };
  61
  62         if (id == "custom") { return; }
  63         document.getElementById("x1").value = presets[id][0];
  64         document.getElementById("x2").value = presets[id][1];
  65         document.getElementById("eq").value = presets[id][2];
  66         plot();
  67       }
  68     </script>
  69   </head>
  70   <body onload="preset()">
  71     <p><b>Equation: </b><br/>
  72     <textarea cols="40" rows="10" id="eq">function(x) {
  73   return [0.1 * x, 0.1 * x + Math.sin(x), 0.1*x + Math.cos(x)];
  74 }</textarea><br/>
  75 <b>Preset functions:</b> <select id=presets onchange="preset()">
  76 <option id=custom>(custom)</option>
  77 <option id=id>Identity</option>
  78 <option id=sine>Sine Wave</option>
  79 <option id=taylor>Taylor series</option>
  80 <option selected id=sawtooth>Sawtooth</option>
  81 </select>
  82     </p>
  83
  84     <p><b>x range: </b> <input type=text width="5" id="x1" value="-10" />
  85     to <input type=text width="5" id="x2" value="10" /></p>
  86     <p><input type=button value="Plot" onClick="plot()" /></p>
  87
  88     <div id="graph_div" style="width:1024px; height:400px;"></div>
  89   </body>
  90 </html>