[dygraphs.git] / tests / linear-regression-addseries.html

<!DOCTYPE html>
<html>
  <head>
    <meta http-equiv="X-UA-Compatible" content="IE=EmulateIE7; IE=EmulateIE9">
    <title>Linear Regression</title>
    <!--[if IE]>
    <script type="text/javascript" src="../excanvas.js"></script>
    <![endif]-->
    <!--
    For production (minified) code, use:
    <script type="text/javascript" src="dygraph-combined.js"></script>
    -->
    <script type="text/javascript" src="../dygraph-dev.js"></script>

    <style type="text/css">
    body { max-width: 640 px; }
    </style>
  </head>
  <body>
    <h2>Linear Regression Demo</h2>
    <p>Click the buttons to generate linear regressions over either data
    series. If you zoom in and click the regression button, the regression will
    only be run over visible points. Zoom back out to see what the local
    regression looks like over the full data.</p>

    <div id="demodiv" style="width: 480px; height: 320px;"></div>

    <script type="text/javascript">
      var data = [];
      for (var i = 0; i < 120; i++) {
        data.push([i,
                   i / 5.0 + 10.0 * Math.sin(i / 3.0),
                   30.0 - i / 5.0 - 10.0 * Math.sin(i / 3.0 + 1.0)]);
      }
      var labels = ['X', 'Y1', 'Y2'];
      var orig_colors = [];

      g = new Dygraph(
              document.getElementById("demodiv"),
              data,
              {
                labels: labels,
                drawPoints: true,
                strokeWidth: 0.0,
                drawCallback: function(g, is_initial) {
                  if (!is_initial) return;
                  var c = g.getColors();
                  for (var i = 0; i < c.length; i++) orig_colors.push(c[i]);
                }
              }
          );

      // coefficients of regression for each series.
      // if coeffs = [ null, [1, 2], null ] then we draw a regression for series 1
      // only. The regression line is y = 1 + 2 * x.
      var coeffs = [ null, null, null ];
      function regression(series) {
        // Only run the regression over visible points.
        var range = g.xAxisRange();

        var sum_xy = 0.0, sum_x = 0.0, sum_y = 0.0, sum_x2 = 0.0, num = 0;
        for (var i = 0; i < data.length; i++) {
          var x = data[i][0];
          if (x < range[0] || x > range[1]) continue;

          var y = data[i][series];
          if (y == null) continue;
          if (y.length == 2) {
            // using fractions
            y = y[0] / y[1];
          }

          num++;
          sum_x += x;
          sum_y += y;
          sum_xy += x * y;
          sum_x2 += x * x;
        }

        var a = (sum_xy - sum_x * sum_y / num) / (sum_x2 - sum_x * sum_x / num);
        var b = (sum_y - a * sum_x) / num;

        coeffs[series] = [b, a];
        if (typeof(console) != 'undefined') {
          console.log("coeffs(" + series + "): [" + b + ", " + a + "]");
        }

        updateChart();
      }

      function updateChart() {
        // Generate a new data set with the regression lines.
        var new_labels = [];
        var new_colors = [];
        var new_opts = {};
        for (var i = 0; i < labels.length; i++) {
          new_labels.push(labels[i]);
          if (i) new_colors.push(orig_colors[i - 1]);
          if (coeffs[i]) {
            // Darken the series by 50% to generate its regression.
            var label = labels[i] + " Regression";
            new_labels.push(label);
            var c = new RGBColor(orig_colors[i - 1]);
            c.r = Math.floor(255 - 0.5 * (255 - c.r));
            c.g = Math.floor(255 - 0.5 * (255 - c.g));
            c.b = Math.floor(255 - 0.5 * (255 - c.b));
            new_colors.push(c.toHex());
            new_opts[label] = {
              drawPoints: false,
              strokeWidth: 1.0
            };
          }
        }

        var new_data = [];
        for (var i = 0; i < data.length; i++) {
          new_data.push([]);
          for (var j = 0; j < data[i].length; j++) {
            new_data[i].push(data[i][j]);
            if (coeffs[j]) {
              new_data[i].push(coeffs[j][0] + coeffs[j][1] * data[i][0]);
            }
          }
        }

        new_opts.file = new_data;
        new_opts.labels = new_labels;
        new_opts.colors = new_colors;
        g.updateOptions(new_opts);
      }

      function clearLines() {
        for (var i = 0; i < coeffs.length; i++) coeffs[i] = null;
        updateChart();
      }
      
    </script>
    
    <div style="position: absolute; left: 500px; top: 150px;">
    <input type=button style="color: green;" value="Regression (Y1)" onClick="regression(1)" />
    <br/><br/>
    <input type=button style="color: blue;" value="Regression (Y2)" onClick="regression(2)" />
    <br/><br/>
    <input type=button value="Clear Lines" onClick="clearLines()" />
    </div>
</body>
</html>
Commit	Line	Data
54425b14	1	<!DOCTYPE html>
34bbe78b DV	2	<html>
34bbe78b DV	3	<head>
10494b48	4	<meta http-equiv="X-UA-Compatible" content="IE=EmulateIE7; IE=EmulateIE9">
34bbe78b DV	5	<title>Linear Regression</title>
34bbe78b DV	6	<!--[if IE]>
a2b2c3a1	7	<script type="text/javascript" src="../excanvas.js"></script>
34bbe78b	8	<![endif]-->
7e5ddc94 DV	9	<!--
	10	For production (minified) code, use:
	11	<script type="text/javascript" src="dygraph-combined.js"></script>
	12	-->
	13	<script type="text/javascript" src="../dygraph-dev.js"></script>
	14
34bbe78b DV	15	<style type="text/css">
	16	body { max-width: 640 px; }
	17	</style>
	18	</head>
	19	<body>
	20	<h2>Linear Regression Demo</h2>
	21	<p>Click the buttons to generate linear regressions over either data
	22	series. If you zoom in and click the regression button, the regression will
	23	only be run over visible points. Zoom back out to see what the local
	24	regression looks like over the full data.</p>
	25
	26	<div id="demodiv" style="width: 480px; height: 320px;"></div>
	27
	28	<script type="text/javascript">
	29	var data = [];
	30	for (var i = 0; i < 120; i++) {
	31	data.push([i,
	32	i / 5.0 + 10.0 * Math.sin(i / 3.0),
	33	30.0 - i / 5.0 - 10.0 * Math.sin(i / 3.0 + 1.0)]);
	34	}
	35	var labels = ['X', 'Y1', 'Y2'];
	36	var orig_colors = [];
	37
	38	g = new Dygraph(
	39	document.getElementById("demodiv"),
	40	data,
	41	{
	42	labels: labels,
	43	drawPoints: true,
de0445fc	44	strokeWidth: 0.0,
34bbe78b DV	45	drawCallback: function(g, is_initial) {
	46	if (!is_initial) return;
	47	var c = g.getColors();
	48	for (var i = 0; i < c.length; i++) orig_colors.push(c[i]);
	49	}
	50	}
	51	);
	52
	53	// coefficients of regression for each series.
	54	// if coeffs = [ null, [1, 2], null ] then we draw a regression for series 1
	55	// only. The regression line is y = 1 + 2 * x.
	56	var coeffs = [ null, null, null ];
	57	function regression(series) {
	58	// Only run the regression over visible points.
	59	var range = g.xAxisRange();
	60
	61	var sum_xy = 0.0, sum_x = 0.0, sum_y = 0.0, sum_x2 = 0.0, num = 0;
	62	for (var i = 0; i < data.length; i++) {
	63	var x = data[i][0];
	64	if (x < range[0] \|\| x > range[1]) continue;
	65
	66	var y = data[i][series];
	67	if (y == null) continue;
d1dfab80 DV	68	if (y.length == 2) {
	69	// using fractions
	70	y = y[0] / y[1];
	71	}
34bbe78b DV	72
	73	num++;
	74	sum_x += x;
	75	sum_y += y;
	76	sum_xy += x * y;
	77	sum_x2 += x * x;
	78	}
	79
	80	var a = (sum_xy - sum_x * sum_y / num) / (sum_x2 - sum_x * sum_x / num);
	81	var b = (sum_y - a * sum_x) / num;
	82
	83	coeffs[series] = [b, a];
4df1af70	84	if (typeof(console) != 'undefined') {
34bbe78b DV	85	console.log("coeffs(" + series + "): [" + b + ", " + a + "]");
	86	}
	87
	88	updateChart();
	89	}
	90
	91	function updateChart() {
	92	// Generate a new data set with the regression lines.
	93	var new_labels = [];
	94	var new_colors = [];
de0445fc	95	var new_opts = {};
34bbe78b DV	96	for (var i = 0; i < labels.length; i++) {
	97	new_labels.push(labels[i]);
	98	if (i) new_colors.push(orig_colors[i - 1]);
	99	if (coeffs[i]) {
	100	// Darken the series by 50% to generate its regression.
227b93cc DV	101	var label = labels[i] + " Regression";
227b93cc DV	102	new_labels.push(label);
34bbe78b DV	103	var c = new RGBColor(orig_colors[i - 1]);
	104	c.r = Math.floor(255 - 0.5 * (255 - c.r));
	105	c.g = Math.floor(255 - 0.5 * (255 - c.g));
	106	c.b = Math.floor(255 - 0.5 * (255 - c.b));
	107	new_colors.push(c.toHex());
227b93cc	108	new_opts[label] = {
de0445fc DV	109	drawPoints: false,
	110	strokeWidth: 1.0
	111	};
34bbe78b DV	112	}
	113	}
	114
	115	var new_data = [];
	116	for (var i = 0; i < data.length; i++) {
	117	new_data.push([]);
	118	for (var j = 0; j < data[i].length; j++) {
	119	new_data[i].push(data[i][j]);
	120	if (coeffs[j]) {
	121	new_data[i].push(coeffs[j][0] + coeffs[j][1] * data[i][0]);
	122	}
	123	}
	124	}
	125
de0445fc DV	126	new_opts.file = new_data;
	127	new_opts.labels = new_labels;
	128	new_opts.colors = new_colors;
	129	g.updateOptions(new_opts);
34bbe78b DV	130	}
	131
	132	function clearLines() {
	133	for (var i = 0; i < coeffs.length; i++) coeffs[i] = null;
	134	updateChart();
	135	}
34bbe78b DV	136
	137	</script>
	138
	139	<div style="position: absolute; left: 500px; top: 150px;">
	140	<input type=button style="color: green;" value="Regression (Y1)" onClick="regression(1)" />
	141	<br/><br/>
	142	<input type=button style="color: blue;" value="Regression (Y2)" onClick="regression(2)" />
	143	<br/><br/>
	144	<input type=button value="Clear Lines" onClick="clearLines()" />
	145	</div>
	146	</body>
	147	</html>