tests/plotter.html

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