+ </code>
+ </div>
+ <div class="codeoutput" style="float:left;">
+ <h3 style="text-align:center">OUTPUT</h3>
+ <div id="graphdiv4" style="width:480px; height:320px;"></div>
+ <script type="text/javascript">
+ g4 = new Dygraph(
+ document.getElementById("graphdiv4"),
+ "twonormals.csv",
+ {
+ rollPeriod: 7,
+ showRoller: true,
+ errorBars: true,
+ valueRange: [50,125]
+ }
+ );
+ </script>
+ </div>
+ </div>
+
+ <p style="clear:both;">Things to note here:</p>
+
+ <ul>
+ <li>The <strong>errorBars</strong> option affects both the interpretation of the CSV file and the display of the graph. When <strong>errorBars</strong> is set to true, each line is interpreted as <em>YYYYMMDD</em>, <em>A</em>, <em>sigma_A</em>, <em>B</em>, <em>sigma_B</em>, …</li>
+ <li>The first line of the CSV file doesn't mention the error columns. In this case, it's just "Date,Series1,Series2".</li>
+ <li>The averaging visibly affects the error bars. This is most clear if you crank up the rolling period to something like 100 days. For the earliest dates, there won't be 100 data points to average so the signal will be noisier. The error bars get smaller like sqrt(N) going forward in time until there's a full 100 points to average.</li>
+ <li>The error bars are partially transparent. This can be seen when they overlap one another.</li>
+ </ul>
+
+ <h2 id="ie">Internet Explorer Compatibility</h2>
+
+ <p>The dygraphs library relies heavily on the HTML5 <code><canvas></code> tag, which Microsoft Internet Explorer did not traditionally support. To use Microsoft's native canvas implementation in IE9, you need to set an HTML5 doctype on your page:</p>
+
+<pre>
+<!DOCTYPE html>
+</pre>
+
+ <p>When IE9 is in HTML5 mode, dygraphs works just like in other modern browsers.</p>
+
+ <p>If you want to support previous versions of Internet Explorer (IE6–IE8), you'll need to include the <a href="http://code.google.com/p/explorercanvas/">excanvas</a> library, which emulates the <code><canvas></code> tag using VML. You can add excanvas by including the following snippet:</p>
+
+<pre>
+<!DOCTYPE html>
+<html>
+ <head>
+ <meta http-equiv="X-UA-Compatible" content="IE=EmulateIE7; IE=EmulateIE9">
+ <!--[if IE]><script src="path/to/excanvas.js"></script><![endif]-->
+ </head>
+</pre>
+
+<p>(This is surprisingly tricky because the HTML5 doctype breaks excanvas in IE8. See <a href="https://groups.google.com/group/dygraphs-users/browse_thread/thread/c60709e04bc7fe5f#">this discussion</a> for details. Note that the <meta http-equiv…> line must appear <i>first</i> in the <head> section for this to work properly.)</p>
+
+ <p>While VML emulation sounds like it would be slow, it works well in practice for most charts.</p>
+
+ <p>One common gotcha to look out for: make sure you don't have any trailing commas in parameter lists, e.g.</p>
+
+<pre>
+new Dygraph(el, data, {
+ showRoller: true, // note trailing comma
+})</pre>
+
+ <p>Most browsers will ignore the trailing comma, but it will break under IE.</p>
+
+ <p>You may also need to delay instantiating any dygraphs until after the DOM
+ content is ready, as there have been some <a
+ href="https://groups.google.com/d/topic/dygraphs-users/qPX4Syx2kz8/discussion">reports</a>
+ that excanvas won't work until this happens. If you're using jQuery, this
+ means drawing your charts inside of a <code>$(function() { ... })</code>
+ block.</p>
+
+ <h2 id="gviz">GViz Data</h2>
+
+ <p>The <a
+ href="http://code.google.com/apis/visualization/documentation/index.html">Google
+ Visualization API</a> provides a standard interface for describing data.
+ Once you've specified your data using this API, you can plug in any
+ GViz-compatible visualization. dygraphs is such a visualization. In
+ particular, it can be used as a drop-in replacement for the
+ AnnotatedTimeline visualization used on Google Finance and other sites. To
+ see how this works, check out the <a href="tests/annotation-gviz.html">gviz
+ annotation demo.</a></p>
+
+ <p>For a simple demonstration of how to use dygraphs a GViz visualization, see <a href="http://danvk.org/dygraphs/tests/gviz.html">http://danvk.org/dygraphs/tests/gviz.html</a>. dygraphs can also be used as a GViz gadget. This allows it to be embedded inside of a Google Spreadsheet. For a demonstration of this, see <a href="http://spreadsheets.google.com/ccc?key=0Anx1yCqeL8YUdDR1c3pPREhraGhkWmdhaURjOXRncXc&hl=en">this spreadsheet</a>. The URL for the gadget is <code><a href="http://danvk.org/dygraphs/gadget.xml">http://danvk.org/dygraphs/gadget.xml</a></code>.</p>
+
+ <p>Here's an example of a published gviz gadget using dygraphs:</p>
+
+ <script src="http://spreadsheets.google.com/gpub?url=http%3A%2F%2Fkb8jbn8l90ocl9n4b14jrcvp61ceqis5.spreadsheets.gmodules.com%2Fgadgets%2Fifr%3Fup__table_query_url%3Dhttp%253A%252F%252Fspreadsheets.google.com%252Ftq%253Frange%253DA1%25253AC31%2526headers%253D-1%2526key%253D0Anx1yCqeL8YUdDR1c3pPREhraGhkWmdhaURjOXRncXc%2526gid%253D0%2526pub%253D1%26up__table_query_refresh_interval%3D300%26url%3Dhttp%253A%252F%252Fdanvk.org%252Fdygraphs%252Fgadget.xml%253Fnocache&height=215&width=530"></script>
+
+ <h2 id="baseball">Charting Fractions</h2>
+
+ <p>Situations often arise where you want to plot fractions, e.g. the fraction of respondents in a poll who said they'd vote for candidate X or the number of hits divided by at bats (baseball's batting average). Fractions require special treatment for two main reasons:</p>
+
+ <ul>
+ <li>The average of <code>a1/b1</code> and <code>a2/b2</code> is <code>(a1+a2)/(b1+b2)</code>, not <code>(a1/b1 + a2/b2)/2</code>.</li>
+ <li>The normal approximation is not always applicable and more sophisticated confidence intervals (e.g. the <a href="http://en.wikipedia.org/wiki/Binomial_proportion_confidence_interval">Wilson confidence interval</a>) must be employed to avoid ratios that exceed 100% or go below 0%.</li>
+ </ul>
+
+ <p>Fortunately, dygraphs handles both of these for you! Here's a chart and the command that generated it:</p>
+
+ <div style="width:750px; text-align:center; font-weight: bold; font-size: 125%;">Batting Average for Ichiro Suzuki vs. Mariners (2004)</div>
+ <div id="baseballdiv" style="width:750px; height:300px;"></div>
+ <script type="text/javascript">
+ new Dygraph(
+ document.getElementById("baseballdiv"),
+ "suzuki-mariners.txt",
+ {
+ fractions: true,
+ errorBars: true,
+ showRoller: true,
+ rollPeriod: 15
+ }
+ );
+ </script>
+
+ <p>Command:</p>
+<pre>
+ new Dygraph(
+ document.getElementById("baseballdiv"),
+ "suzuki-mariners.txt",
+ {
+ fractions: true,
+ errorBars: true,
+ showRoller: true,
+ rollPeriod: 15
+ }
+ );
+</pre>
+
+ <p>The <code>fractions</code> option indicates that the values in each column should be parsed as fractions (e.g. "1/2" instead of "0.5"). The <code>errorBars</code> option indicates that we'd like to see a confidence interval around each data point. By default, when <code>fractions</code> is set, you get a Wilson confidence interval. If you look carefully at the chart, you can see that the error bars are asymmetric.</p>
+
+ <p>A couple things to notice about this chart:</p>
+
+ <ul>
+ <li>The error bars for Ichiro's batting average are larger than for the Mariners', since he has far fewer at bats than his team.</li>
+ <li>dygraphs makes it easy to see "batting average over the last 30 games". This is ordinarily quite difficult to compute. It makes it clear where the "hot" and "cold" part of Suzuki's season were.</li>
+ <li>If you set the averaging period to something large, like 200, you'll see the team's and player's batting average through that game. The final number is the overall batting average for the season.</li>
+ <li>Where the error bars do not overlap, we can say with 95% confidence that the series differ. There is a better than 95% chance that Ichiro was a better hitter than his team as a whole in 2004, the year he won the batting title.</li>
+ </ul>
+
+ <h2 id="stock">One last demo</h2>
+
+ <p>This chart shows monthly closes of the Dow Jones Industrial Average, both in nominal and real (i.e. adjusted for inflation) dollars. The shaded areas show its monthly high and low. CPI values with a base from 1982-84 are used to adjust for inflation.</p>
+
+ <div id="dow_chart" style="width:750px; height:350px;"></div>
+ <p><b>Display: </b>
+ <input type=checkbox id=0 onClick="stockchange(this)" checked>
+ <label for="0"> Nominal</label>
+ <input type=checkbox id=1 onClick="stockchange(this)" checked>
+ <label for="1"> Real</label>
+ <input type=checkbox id=ann onClick="annotationschange(this)" checked>
+ <label for="ann"> Annotations</label>
+ </p>
+
+ <script type="text/javascript">
+ var stock_annotations = [
+ {
+ series: "Real",
+ x: "1929-08-15",
+ shortText: "A",
+ text: "1929 Stock Market Peak"
+ },
+ {
+ series: "Nominal",
+ x: "1987-08-15",
+ shortText: "B",
+ text: "1987 Crash"
+ },
+ {
+ series: "Nominal",
+ x: "1999-12-15",
+ shortText: "C",
+ text: "1999 (.com) Peak"
+ },
+ {
+ series: "Nominal",
+ x: "2007-10-15",
+ shortText: "D",
+ text: "All-Time Market Peak"
+ }
+ ];
+
+ // From http://www.econstats.com/eqty/eq_d_mi_3.csv
+ stockchart = new Dygraph(
+ document.getElementById('dow_chart'),
+ "dow.txt",
+ {
+ showRoller: true,
+ customBars: true,
+ labelsKMB: true,
+ drawCallback: function(g, is_initial) {
+ if (!is_initial) return;
+ g.setAnnotations( stock_annotations );