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   4     <title>dygraphs JavaScript Visualization Library</title>
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   8     <script type="text/javascript" src="dygraph-combined.js"></script>
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  13       <h2>Documentation</h2>
  14       <ul>
  15         <li><a href="#demo">Demo</a></li>
  16         <li><a href="#usage">Usage</a></li>
  17         <li><a href="#ie">IE Compatibility</a></li>
  18         <li><a href="#gviz">GViz Data</a></li>
  19         <li><a href="#baseball">Baseball chart</a></li>
  20         <li><a href="#stock">Stock chart</a></li>
  21         <li><a href="#options">Options Reference</a></li>
  22         <li><a href="#gwt">GWT Compatibility</a></li>
  23         <li><a href="#policy">Data Policy</a></li>
  24       </ul>
  25
  26       <h2>Project</h2>
  27       <ul>
  28         <li><a href="http://github.com/danvk/dygraphs">Source</a></li>
  29         <li><a href="http://code.google.com/p/dygraphs/issues/">Issues</a></li>
  30         <li><a href="http://code.google.com/p/dygraphs/issues/entry">Report Bug</a></li>
  31         <li><a href="mailto:dygraphs-users [at] googlegroups.com">Contact</a></li>
  32       </ul>
  33
  34       <h2>Gallery</h2>
  35       <ul>
  36         <li><a href="tests/demo.html">Basic Demo</a></li>
  37         <li><a href="tests/gviz.html">GViz Demo</a></li>
  38         <li><a href="tests/plotter.html">Equation Plotter</a></li>
  39         <li><a href="tests/perf.html">Performance Test</a></li>
  40         <li><a href="tests/fillGraph.html">Filled Chart</a></li>
  41         <li><a href="tests/perf.html">Fractions</a></li>
  42         <li><a href="tests/visibility.html">Visibility</a></li>
  43         <li><a href="tests/label-div.html">Labels in a DIV</a></li>
  44         <li><a href="tests/numeric-axis.html">Numeric Axis</a></li>
  45         <li><a href="tests/draw-points.html">Dotted Points</a></li>
  46         <li><a href="tests/native-format.html">Native Format</a></li>
  47         <li><a href="tests/grid_dot.html">Crazy Styles</a></li>
  48         <li><a href="tests/spacing.html">Tick spacing</a></li>
  49         <li><a href="tests/callback.html">Callbacks</a></li>
  50         <li><a href="tests/crosshair.html">Crosshairs</a></li>
  51         <li><a href="tests/hourly.html">Hourly/Minutely data</a></li>
  52         <li><a href="tests/isolated-points.html">Isolated Points</a></li>
  53         <li><a href="tests/missing-data.html">Missing Data</a></li>
  54         <li><a href="tests/border.html">Bordered chart</a></li>
  55         <li><a href="tests/custom-bars.html">Custom Bars</a></li>
  56         <li><a href="tests/customLabel.html">Custom Label Styles</a></li>
  57         <li><a href="tests/dygraph.html">Minimal Example</a></li>
  58         <li><a href="tests/negative.html">Negative Numbers</a></li>
  59         <li><a href="tests/noise.html">Noisy Data</a></li>
  60         <li><a href="tests/two-series.html">Multiple Series</a></li>
  61         <li><a href="tests/underlay-callback.html">Custom Underlay / background</a></li>
  62       </ul>
  63     </div>
  64
  65     <div id="content">
  66       <h1>dygraphs JavaScript Visualization Library</h1>
  67
  68       <p><a href="http://github.com/danvk/dygraphs">http://github.com/danvk/dygraphs</a></p>
  69       <p>See <a href="http://groups.google.com/group/dygraphs-users">mailing list</a>, <a href="http://github.com/danvk/dygraphs/downloads/">downloads</a>, <a href="tests/">gallery</a> and <a href="http://code.google.com/p/dygraphs/issues/">open issues</a></p>
  70
  71       <p>dygraphs is an open source JavaScript library that produces produces interactive, zoomable charts of time series. It is designed to display dense data sets and enable users to explore and interpret them.</p>
  72
  73       <h3 id="demo">A demo is worth a thousand words:</h3>
  74
  75       <p style="font-size:0.8em">(Mouse over to highlight individual values. Click and drag to zoom. Double-click to zoom back out. Change the number and hit enter to adjust the averaging period.)</p>
  76
  77       <div id="title" style="width:800px; margin: 1em;text-align:center; font-weight: bold; font-size: 125%;">Temperatures in New York vs. San Francisco</div>
  78
  79       <div id="demodiv" style="width:800px; height:320px;"></div>
  80       <script type="text/javascript">
  81         g = new Dygraph(
  82           document.getElementById("demodiv"),
  83           "ny-vs-sf.txt",
  84           {
  85             rollPeriod: 14,
  86             showRoller: true,
  87             customBars: true,
  88             yAxisLabelWidth: 30
  89           }
  90         );
  91       </script>
  92
  93       <h4>Some things to notice:</h4>
  94       <ul>
  95         <li>There's less seasonal temperature variation in SF than in NY.</li>
  96         <li>The difference is about 15&deg; F for SF vs. 50&deg; F for NY.</li>
  97         <li>The daily data (set rolling period to 1) is quite noisy and hides this conclusion.</li>
  98         <li>Using a 14-day moving average makes it clearer. A 100-day rolling period averages out nearly all the specifics from the data.</li>
  99         <li>There's a gap in the data for SF, when the weather station was down (zoom into October 2007 to see it).</li>
 100         <li>The bands around each point indicate average highs and lows.</li>
 101         <li>There is a <em>lot</em> of data in this chart: low, average and high for each city on each day of a three year period &asymp; 6000 data points in all.</li>
 102       </ul>
 103
 104       <p>dygraphs allows the user to explore the data and discover these facts.</p>
 105
 106       <p>For more demos, browse the dygraph <a href="tests/">tests</a> directory.</p>
 107
 108       <h3>Features</h3>
 109       <p>Some of the features of dygraphs:</p>
 110       <ul>
 111         <li>Plots time series without using an external server or Flash</li>
 112         <li>Works in Internet Explorer (using excanvas)</li>
 113         <li>Lightweight (45kb) and responsive</li>
 114         <li>Displays values on mouseover (this makes it easily discoverable)</li>
 115         <li>Supports error bands around data series</li>
 116         <li>Interactive zoom</li>
 117         <li>Adjustable averaging period</li>
 118         <li>Can intelligently chart fractions</li>
 119         <li>Customizable click-through actions</li>
 120         <li>Compatible with the Google Visualization API</li>
 121         <li>Intelligent defaults make it easy to use</li>
 122       </ul>
 123
 124       <h2 id="usage">Usage</h2>
 125
 126       <p>To use dygraphs, include the <code><a href="http://github.com/danvk/dygraphs/downloads/">dygraph-combined.js</a></code> JavaScript file and instantiate a <code>Dygraph</code> object.</p>
 127
 128       <p>Here's a basic example to get things started:</p>
 129
 130       <div class="example" style="clear:both;">
 131         <div class="codeblock" style="float:left;width:400px;">
 132           <h3 style="text-align:center">HTML</h3>
 133           <code>
 134   <pre>
 135 &lt;html&gt;
 136 &lt;head&gt;
 137 &lt;script type=&quot;text/javascript&quot;
 138   src=&quot;dygraph-combined.js&quot;&gt;&lt;/script&gt;
 139 &lt;/head&gt;
 140 &lt;body&gt;
 141 &lt;div id=&quot;graphdiv&quot;&gt;&lt;/div&gt;
 142 &lt;script type=&quot;text/javascript&quot;&gt;
 143   g = new Dygraph(
 144
 145     // containing div
 146     document.getElementById(&quot;graphdiv&quot;),
 147
 148     // CSV or path to a CSV file.
 149     &quot;Date,Temperature\n&quot; +
 150     &quot;2008-05-07,75\n&quot; +
 151     &quot;2008-05-08,70\n&quot; +
 152     &quot;2008-05-09,80\n&quot;
 153
 154   );
 155 &lt;/script&gt;
 156 &lt;/body&gt;
 157 &lt;/html&gt;
 158 </pre>
 159           </code>
 160         </div>
 161         <div class="codeoutput" style="float:left;">
 162           <h3 style="text-align:center">OUTPUT</h3>
 163           <div id="graphdiv"></div>
 164           <script type="text/javascript">
 165             g = new Dygraph(
 166
 167               // containing div
 168               document.getElementById("graphdiv"),
 169
 170               // CSV or path to a CSV file.
 171               "Date,Temperature\n" +
 172               "2008-05-07,75\n" +
 173               "2008-05-08,70\n" +
 174               "2008-05-09,80\n"
 175             );
 176           </script>
 177         </div>
 178       </div>
 179
 180       <p style="clear:both">In order to keep this example self-contained, the second parameter is raw CSV data. The dygraphs library parses this data (including column headers), resizes its container to a reasonable default, calculates appropriate axis ranges and tick marks and draws the graph.</p>
 181
 182       <p>In most applications, it makes more sense to include a CSV file instead. If the second parameter to the constructor doesn't contain a newline, it will be interpreted as the path to a CSV file. The Dygraph will perform an XMLHttpRequest to retrieve this file and display the data when it becomes available. Make sure your CSV file is readable and serving from a place that understands XMLHttpRequest's! In particular, you cannot specify a CSV file using <code>"file:///"</code>. Here's an example: (data from <a href="http://www.wunderground.com/history/airport/KNUQ/2007/1/1/CustomHistory.html?dayend=31&amp;monthend=12&amp;yearend=2007&amp;req_city=NA&amp;req_state=NA&amp;req_statename=NA">Weather Underground</a>)</p>
 183
 184       <div class="example" style="clear:both;">
 185         <div class="codeblock" style="float:left;width:400px;">
 186           <h3 style="text-align:center">HTML</h3>
 187           <code>
 188 <pre>
 189 &lt;html&gt;
 190 &lt;head&gt;
 191 &lt;script type=&quot;text/javascript&quot;
 192   src=&quot;dygraph-combined.js&quot;&gt;&lt;/script&gt;
 193 &lt;/head&gt;
 194 &lt;body&gt;
 195 &lt;div id=&quot;graphdiv2&quot;
 196   style=&quot;width:500px; height:300px;&quot;&gt;&lt;/div&gt;
 197 &lt;script type=&quot;text/javascript&quot;&gt;
 198   g2 = new Dygraph(
 199     document.getElementById(&quot;graphdiv2&quot;),
 200     &quot;temperatures.csv&quot;, // path to CSV file
 201     {}          // options
 202   );
 203 &lt;/script&gt;
 204 &lt;/body&gt;
 205 &lt;/html&gt;
 206 </pre>
 207           </code>
 208         </div>
 209         <div class="codeoutput" style="float:left;">
 210           <h3 style="text-align:center">OUTPUT</h3>
 211           <div id="graphdiv2" style="width:500px; height:300px;"></div>
 212           <script type="text/javascript">
 213             g2 = new Dygraph(
 214               document.getElementById("graphdiv2"),
 215               "temperatures.csv",
 216               {}
 217             );
 218           </script>
 219         </div>
 220       </div>
 221
 222       <p style="clear:both;">The file used is <code><a href="temperatures.csv">temperatures.csv</a></code>.</p>
 223
 224       <p>There are a few things to note here:</p>
 225
 226       <ul>
 227         <li>The Dygraph sent off an XHR to get the temperatures.csv file.</li>
 228         <li>The labels were taken from the first line of <code>temperatures.csv</code>, which is <code>Date,High,Low</code>.</li>
 229         <li>The Dygraph automatically chose two different, easily-distinguishable colors for the two data series.</li>
 230         <li>The labels on the x-axis have switched from days to months. If you zoom in, they'll switch to weeks and then days.</li>
 231         <li>Some heuristics are used to determine a good vertical range for the data. The idea is to make all the data visible and have human-friendly values on the axis (i.e. 200 instead of 193.4). Generally this works well.</li>
 232         <li>The data is very spiky. A moving average would be easier to interpret.</li>
 233       </ul>
 234
 235       <p>This problem can be fixed by specifying the appropriate options in the "additional options" parameter to the Dygraph constructor. To set the number of days for a moving average, use the <code>rollPeriod</code> option. Here's how it's done:</p>
 236
 237       <div class="example" style="clear:both;">
 238         <div class="codeblock" style="float:left;width:400px;">
 239           <h3 style="text-align:center">HTML</h3>
 240           <code>
 241 <pre>
 242 &lt;html&gt;
 243 &lt;head&gt;
 244 &lt;script type=&quot;text/javascript&quot;
 245   src=&quot;dygraph-combined.js&quot;&gt;&lt;/script&gt;
 246 &lt;/head&gt;
 247 &lt;body&gt;
 248 &lt;div id=&quot;graphdiv3&quot;
 249   style=&quot;width:500px; height:300px;&quot;&gt;&lt;/div&gt;
 250 &lt;script type=&quot;text/javascript&quot;&gt;
 251   g3 = new Dygraph(
 252     document.getElementById(&quot;graphdiv3&quot;),
 253     &quot;temperatures.csv&quot;,
 254     {
 255       rollPeriod: 7,
 256       showRoller: true
 257     }
 258   );
 259 &lt;/script&gt;
 260 &lt;/body&gt;
 261 &lt;/html&gt;
 262 </pre>
 263           </code>
 264         </div>
 265         <div class="codeoutput" style="float:left;">
 266           <h3 style="text-align:center">OUTPUT</h3>
 267           <div id="graphdiv3" style="width:500px; height:300px;"></div>
 268           <script type="text/javascript">
 269             g3 = new Dygraph(
 270               document.getElementById("graphdiv3"),
 271               "temperatures.csv",
 272               {
 273                 rollPeriod: 7,
 274                 showRoller: true
 275               }
 276             );
 277           </script>
 278         </div>
 279       </div>
 280
 281       <p style="clear:both;">A rolling average can be set using the text box in the lower left-hand corner of the graph (the showRoller attribute is what makes this appear). Also note that we've explicitly set the size of the chart div.</p>
 282
 283       <h2>Error Bars</h2>
 284
 285       <p>Another significant feature of the dygraphs library is the ability to display error bars around data series. One standard deviation must be specified for each data point. A <em>&plusmn;n</em> sigma band will be drawn around the data series at that point. If a moving average is being displayed, dygraphs will compute the standard deviation of the average at each point. I.E. <em>&sigma; = sqrt( (&sigma;<sub>1<sup>2</sup></sub> + &sigma;<sub>2<sup>2</sup></sub> + ... + &sigma;<sub>n<sup>2</sup></sub>) / n )</em></p>
 286
 287       <p>Here's a demonstration. There are two data series. One is <code>N(100,10)</code> with a standard deviation of 10 specified at each point. The other is <code>N(80,20)</code> with a standard deviation of 20 specified at each point. The CSV file was generated using Octave and can be viewed at <a href="twonormals.csv">twonormals.csv</a>.</p>
 288
 289       <div class="example" style="clear:both;">
 290         <div class="codeblock" style="float:left;width:400px;">
 291           <h3 style="text-align:center">HTML</h3>
 292           <code>
 293 <pre>
 294 &lt;html&gt;
 295 &lt;head&gt;
 296 &lt;script type=&quot;text/javascript&quot;
 297   src=&quot;combined.js&quot;&gt;&lt;/script&gt;
 298 &lt;/head&gt;
 299 &lt;body&gt;
 300 &lt;div id=&quot;graphdiv4&quot;
 301   style=&quot;width:600px; height:300px;&quot;&gt;&lt;/div&gt;
 302 &lt;script type=&quot;text/javascript&quot;&gt;
 303   g4 = new Dygraph(
 304     document.getElementById(&quot;graphdiv4&quot;),
 305     &quot;twonormals.csv&quot;,
 306     {
 307       rollPeriod: 7,
 308       showRoller: true,
 309       errorBars: true,
 310       valueRange: [50,125]
 311     }
 312   );
 313 &lt;/script&gt;
 314 &lt;/body&gt;
 315 &lt;/html&gt;
 316 </pre>
 317           </code>
 318         </div>
 319         <div class="codeoutput" style="float:left;">
 320           <h3 style="text-align:center">OUTPUT</h3>
 321           <div id="graphdiv4" style="width:600px; height:300px;"></div>
 322           <script type="text/javascript">
 323             g4 = new Dygraph(
 324               document.getElementById("graphdiv4"),
 325               "twonormals.csv",
 326               {
 327                 rollPeriod: 7,
 328                 showRoller: true,
 329                 errorBars: true,
 330                 valueRange: [50,125]
 331               }
 332             );
 333           </script>
 334         </div>
 335       </div>
 336
 337       <p style="clear:both;">Things to note here:</p>
 338
 339       <ul>
 340         <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>, &hellip;</li>
 341         <li>The first line of the CSV file doesn't mention the error columns. In this case, it's just "Date,Series1,Series2".</li>
 342         <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>
 343         <li>The error bars are partially transparent. This can be seen when they overlap one another.</li>
 344       </ul>
 345
 346       <h2 id="ie">Internet Explorer Compatibility</h2>
 347
 348       <p>The dygraphs library relies heavily on HTML's <code>&lt;canvas&gt;</code> tag, which Microsoft Internet Explorer does not support. Fortunately, some clever engineers created the <a href="http://code.google.com/p/explorercanvas/">excanvas</a> library, which implements the <code>&lt;canvas&gt;</code> tag in IE using VML.</p>
 349
 350       <p>You can add IE support to any page using dygraphs by including the following in your page:</p>
 351
 352 <pre>
 353 &lt;head&gt;
 354   &lt;!--[if IE]&gt;&lt;script src="excanvas.js"&gt;&lt;/script&gt;&lt;![endif]--&gt;
 355 &lt;/head&gt;
 356 </pre>
 357
 358     <p>This works quite well in practice. Charts are responsive, even under VML emulation.</p>
 359
 360     <p>One common gotcha to look out for: make sure you don't have any trailing commas in parameter lists, e.g.</p>
 361
 362 <pre>
 363 new Dygraph(el, data, {
 364   showRoller: true,  // note trailing comma
 365 })</pre>
 366
 367     <p>Most browsers will ignore the trailing comma, but it will break under IE.</p>
 368
 369     <h2 id="gviz">GViz Data</h2>
 370
 371     <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.</p>
 372
 373     <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&amp;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>
 374
 375     <p>Here's an example of a published gviz gadget using dygraphs:</p>
 376
 377     <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>
 378
 379     <h2 id="baseball">Charting Fractions</h2>
 380
 381     <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>
 382
 383     <ul>
 384       <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>
 385       <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>
 386     </ul>
 387
 388     <p>Fortunately, dygraphs handles both of these for you! Here's a chart and the command that generated it:</p>
 389
 390     <div style="width:750px; text-align:center; font-weight: bold; font-size: 125%;">Batting Average for Ichiro Suzuki vs. Mariners (2004)</div>
 391     <div id="baseballdiv" style="width:750px; height:300px;"></div>
 392     <script type="text/javascript">
 393       new Dygraph(
 394         document.getElementById("baseballdiv"),
 395         "suzuki-mariners.txt",
 396         {
 397           fractions: true,
 398           errorBars: true,
 399           showRoller: true,
 400           rollPeriod: 15
 401         }
 402       );
 403     </script>
 404
 405     <p>Command:</p>
 406 <pre>
 407   new Dygraph(
 408     document.getElementById(&quot;baseballdiv&quot;),
 409     &quot;suzuki-mariners.txt&quot;,
 410     {
 411       fractions: true,
 412       errorBars: true,
 413       showRoller: true,
 414       rollPeriod: 15
 415     }
 416   );
 417 </pre>
 418
 419     <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>
 420
 421     <p>A couple things to notice about this chart:</p>
 422
 423     <ul>
 424       <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>
 425       <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>
 426       <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>
 427       <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>
 428     </ul>
 429
 430     <h2 id="stock">One last demo</h2>
 431
 432     <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>
 433
 434     <div id="dow_chart" style="width:900px; height:350px;"></div>
 435     <p><b>Display: </b>
 436     <input type=checkbox id=0 onClick="stockchange(this)" checked>
 437     <label for="0"> Nominal</label>
 438     <input type=checkbox id=1 onClick="stockchange(this)" checked>
 439     <label for="1"> Real</label>
 440     </p>
 441
 442     <script type="text/javascript">
 443     // From http://www.econstats.com/eqty/eq_d_mi_3.csv
 444       stockchart = new Dygraph(
 445         document.getElementById('dow_chart'),
 446         "dow.txt",
 447         {
 448           showRoller: true,
 449           customBars: true,
 450           labelsKMB: true
 451         }
 452       );
 453
 454       function stockchange(el) {
 455         stockchart.setVisibility(el.id, el.checked);
 456       }
 457     </script>
 458 <!--
 459
 460 Here is a script to regenerate the Dow Jones plot:
 461
 462 # Get unadjusted DJIA data in a nice format:
 463 curl -O http://www.econstats.com/eqty/eq_d_mi_3.csv
 464 sed '1,17d' eq_d_mi_3.csv | cut -d, -f1,6 | perl -pe 's/(\d{4}-\d\d)-\d\d/$1/g' | perl -pe 's/, */\t/' | grep -v 'na' | perl -ne 'chomp; ($m,$v) = split/\t/; $close{$m} = $v; if ($low{$m} == 0 || $v < $low{$m}) { $low{$m}=$v } if ($v > $high{$m}) { $high{$m} = $v } END { for $x(sort keys %close) { print "$x\t$low{$x}\t$close{$x}\t$high{$x}\n" } } ' > monthly-djia.tsv
 465
 466 # Fetch and format the CPI data:
 467 curl 'http://data.bls.gov/PDQ/servlet/SurveyOutputServlet?series_id=CUUR0000SA0&years_option=all_years&periods_option=all_periods&output_type=column&output_format=text&delimiter=comma' > cpi-u.txt
 468 sed '1,/Series Id,Year,/d' cpi-u.txt | sed '/^$/,$d' | cut -d, -f2,3,4 | perl -ne 'print if /,M(0[0-9]|1[012]),/' | perl -pe 's/(\d{4}),M(\d{2}),/$1-$2\t/g' > cpi-u.tsv
 469
 470 # Merge:
 471 join -t'     ' cpi-u.tsv monthly-djia.tsv > annotated-djia.tsv
 472 perl -ne 'BEGIN{print "Month,Nominal,Real\n"} chomp; ($m,$cpi,$low,$close,$high) = split /\t/; $cpi /= 100.0; print "$m-15,$low;$close;$high,",($low/$cpi),";",($close/$cpi),";",($high/$cpi),"\n"' annotated-djia.tsv > dow.txt
 473
 474 -->
 475
 476     <h2 id="options">Other Options</h2>
 477
 478     <p>These are the options that can be passed in through the optional third parameter of the Dygraph constructor. Under each option is a set of links to tests which demonstrate its use. While we attempt to keep this list up-to-date, a more complete list can be found in the <code>Dygraph.DEFAULT_ATTRS</code> map in <code>dygraph.js</code> and the <code>this.options</code> map in <code>dygraph-canvas.js</code>.</p>
 479
 480     <table class="thinborder" width="900">
 481       <thead>
 482         <tr>
 483           <th width="150">Name</th>
 484           <th width="200">Values</th>
 485           <th width="150">Default</th>
 486           <th>Description</th>
 487         </tr>
 488       </thead>
 489       <tbody>
 490         <tr>
 491           <td><strong>includeZero</strong></td>
 492           <td><code>boolean</code></td>
 493           <td><code>false</code></td>
 494         <td>Usually, dygraphs will use the range of the data plus some padding to set the range of the y-axis. If this option is set, the y-axis will always include zero, typically as the lowest value. This can be used to avoid exaggerating the variance in the data.
 495         <div class="tests">Tests: <a href="tests/no-range.html">no-range</a> <a href="tests/numeric-gviz.html">numeric-gviz</a> <a href="tests/small-range-zero.html">small-range-zero</a> </div>
 496           </td>
 497         </tr>
 498         <tr>
 499           <td><strong>rollPeriod</strong></td>
 500           <td><code>integer &gt;= 1</code></td>
 501           <td><code>1</code></td>
 502           <td>Number of days over which to average data. Discussed extensively above.
 503         <div class="tests">Tests: <a href="tests/demo.html">demo</a> <a href="tests/two-series.html">two-series</a> <a href="tests/noise.html">noise</a> </div>
 504         </td>
 505         </tr>
 506         <tr>
 507           <td><strong>showRoller</strong></td>
 508           <td><code>boolean</code></td>
 509           <td><code>false</code></td>
 510           <td>If the rolling average period text box should be shown.
 511           <div class="tests">Tests: <a href="tests/callback.html">callback</a> <a href="tests/crosshair.html">crosshair</a> <a href="tests/fractions.html">fractions</a> <a href="tests/isolated-points.html">isolated-points</a> <a href="tests/numeric-gviz.html">numeric-gviz</a> <a href="tests/underlay-callback.html">underlay-callback</a> </div>
 512           </td>
 513         </tr>
 514         <tr>
 515           <td><strong>colors</strong></td>
 516           <td><code>['red', '#00FF00']</code></td>
 517           <td><code></code></td>
 518           <td>List of colors for the data series. These can be of the form "#AABBCC" or "rgb(255,100,200)" or "yellow", etc. If not specified, equally-spaced points around a color wheel are used.
 519           <div class="tests">Tests: <a href="tests/color-visibility.html">color-visibility</a> <a href="tests/demo.html">demo</a> </div>
 520           </td>
 521         </tr>
 522         <tr>
 523           <td><strong>fillGraph</strong></td>
 524           <td><code>boolean<br/></code></td>
 525           <td><code>false</code></td>
 526           <td>Should the area underneath the graph be filled? This option is not
 527           compatible with error bars.
 528           <div class="tests">Tests: <a href="tests/fillGraph.html">fillGraph</a> </div>
 529           </td>
 530         </tr>
 531         <tr>
 532           <td><strong>visibility</strong></td>
 533           <td><code>Array of booleans<br/></code></td>
 534           <td><code>[true, true, ...]</code></td>
 535           <td>Which series should initially be visible? Once the Dygraph has
 536           been constructed, you can access and modify the visibility of each
 537           series using the <code>visibility</code> and
 538           <code>setVisibility</code> methods.
 539           <div class="tests">Tests: <a href="tests/visibility.html">visibility</a> <a href="tests/color-visibility.html">color-visibility</a> </div>
 540           </td>
 541         </tr>
 542         <tr>
 543           <td><strong>colorSaturation</strong></td>
 544           <td><code>0.0 - 1.0</code></td>
 545           <td><code>1.0</code></td>
 546           <td>If <strong>colors</strong> is not specified, saturation of the automatically-generated data series colors.
 547           <div class="tests">Tests: <font color=red>none</font></div>
 548           </td>
 549         </tr>
 550         <tr>
 551           <td><strong>colorValue</strong></td>
 552           <td><code>float (0.0 &mdash; 1.0)</code></td>
 553           <td><code>1.0</code></td>
 554           <td>If colors is not specified, value of the data series colors, as in hue/saturation/value. (0.0-1.0, default 0.5)
 555           <div class="tests">Tests: <font color=red>none</font></div>
 556           </td>
 557         </tr>
 558         <tr>
 559           <td><strong>clickCallback</strong></td>
 560           <td><code>function(e, date){<br>&nbsp;&nbsp;&nbsp;&nbsp;alert(date);<br>}</code></td>
 561           <td><code>null</code></td>
 562           <td>A function to call when a data point is clicked. The function should take two arguments, the event object for the click and the date that was clicked. (default null)
 563           <div class="tests">Tests: <a href="tests/callback.html">callback</a> </div>
 564           </td>
 565         </tr>
 566         <tr>
 567           <td><strong>zoomCallback</strong></td>
 568           <td><code>function(minDate,<br/>maxDate){}</code></td>
 569           <td><code>null</code></td>
 570           <td>A function to call when the zoom window is changed (either by zooming in or out). minDate and maxDate are milliseconds since epoch.
 571           <div class="tests">Tests: <a href="tests/callback.html">callback</a> </div>
 572           </td>
 573         </tr>
 574         <tr>
 575           <td><strong>strokeWidth</strong></td>
 576           <td><code>integer</code></td>
 577           <td><code>1</code></td>
 578           <td>Width of the data lines. This can be used to increase the contrast or some graphs.
 579           <div class="tests">Tests: <font color=red>none</font></div>
 580           </td>
 581         </tr>
 582         <tr>
 583           <td><strong>dateWindow</strong></td>
 584           <td><code>[<br>&nbsp;&nbsp;Date.parse('2006-01-01'),<br>&nbsp;&nbsp;(new Date()).valueOf()<br>]</code></td>
 585           <td rowspan="2"><code>Full range of the<br/> input is shown</code></td>
 586           <td>Initially zoom in on a section of the graph. Is of the form [earliest, latest], where earliest/latest are milliseconds since epoch.
 587           <div class="tests">Tests: <a href="tests/dateWindow.html">dateWindow</a> <a href="tests/link-interaction.html">link-interaction</a> </div>
 588           </td>
 589         </tr>
 590         <tr>
 591           <td><strong>valueRange</strong></td>
 592           <td><code>[10, 110]</code></td>
 593           <td>Explicitly set the vertical range of the graph to [low, high].
 594           <div class="tests">Tests: <font color=red>none</font></div>
 595           </td>
 596         </tr>
 597         <tr>
 598           <td><strong>labelsSeparateLines</strong></td>
 599           <td><code>boolean</code></td>
 600           <td><code>false</code></td>
 601           <td>Put <code>&lt;br/&gt;</code> between lines in the label string. Often used in conjunction with <strong>labelsDiv</strong>.
 602           <div class="tests">Tests: <a href="tests/customLabel.html">customLabel</a> <a href="tests/demo.html">demo</a> </div>
 603           </td>
 604         </tr>
 605         <tr>
 606           <td><strong>labelsDiv</strong></td>
 607           <td><code>document.<br/>getElementById('foo')</code></td>
 608           <td><code>null</code></td>
 609           <td>Show data labels in an external div, rather than on the graph.
 610           <div class="tests">Tests: <a href="tests/demo.html">demo</a> <a href="tests/label-div.html">label-div</a> </div>
 611           </td>
 612         </tr>
 613         <tr>
 614           <td><strong>labelsKMB</strong></td>
 615           <td><code>true</code></td>
 616           <td><code>false</code></td>
 617           <td>Show K/M/B for thousands/millions/billions on y-axis.
 618           <div class="tests">Tests: <a href="tests/demo.html">demo</a> <a href="tests/labelsKMB.html">labelsKMB</a> <a href="tests/no-range.html">no-range</a> </div>
 619           </td>
 620         </tr>
 621         <tr>
 622           <td><strong>labelsKMG2</strong></td>
 623           <td><code>true</code></td>
 624           <td><code>false</code></td>
 625           <td>Show k/M/G for kilo/Mega/Giga on y-axis. This is different than
 626           <code>labelsKMB</code> in that it uses base 2, not 10.
 627           <div class="tests">Tests: <a href="tests/labelsKMB.html">labelsKMB</a> </div>
 628           </td>
 629         </tr>
 630         <tr>
 631           <td><strong>labelsDivWidth</strong></td>
 632           <td><code>250</code></td>
 633           <td><code></code></td>
 634           <td>Width (in pixels) of the div which shows information on the currently-highlighted points.
 635           <div class="tests">Tests: <a href="tests/customLabel.html">customLabel</a> </div>
 636           </td>
 637         </tr>
 638         <tr>
 639           <td><strong>labelsDivStyles</strong></td>
 640           <td><code>{}</code></td>
 641           <td><code>null</code></td>
 642           <td>Additional styles to apply to the currently-highlighted points div. For example, { 'font-weight': 'bold' } will make the labels bold.
 643           <div class="tests">Tests: <a href="tests/border.html">border</a> <a href="tests/customLabel.html">customLabel</a> </div>
 644           </td>
 645         </tr>
 646         <tr>
 647           <td><strong>highlightCircleSize</strong></td>
 648           <td><code>integer</code></td>
 649           <td><code>3</code></td>
 650           <td>The size in pixels of the dot drawn over highlighted points.
 651           <div class="tests">Tests: <a href="tests/grid_dot.html">grid_dot</a> </div>
 652           </td>
 653         </tr>
 654         <tr>
 655           <td><strong>drawPoints</strong></td>
 656           <td><code>boolean</code></td>
 657           <td><code>false</code></td>
 658           <td>Draw a small dot at each point, in addition to a line going through the point. This makes the individual data points easier to see, but can increase visual clutter in the chart.
 659           <div class="tests">Tests: <a href="tests/draw-points.html">draw-points</a> </div>
 660           </td>
 661         </tr>
 662         <tr>
 663           <td><strong>pointSize</strong></td>
 664           <td><code>interger</code></td>
 665           <td><code>1</code></td>
 666           <td>The size of the dot to draw on each point in pixels (see drawPoints). A dot is always drawn when a point is "isolated", i.e. there is a missing point on either side of it. This also controls the size of those dots.
 667           <div class="tests">Tests: <font color=red>none</font></div>
 668           </td>
 669         </tr>
 670         <tr>
 671           <td><strong>pixelsPerXLabel</strong></td>
 672           <td rowspan="2"><code>integer</code></td>
 673           <td><code>60</code></td>
 674           <td rowspan="2">Number of pixels to require between each x- and y-label. Larger values will yield a sparser axis with fewer ticks.
 675           <div class="tests">Tests: <a href="tests/spacing.html">spacing</a> </div>
 676           </td>
 677         </tr>
 678         <tr>
 679           <td><strong>pixelsPerYLabel</strong></td>
 680           <td><code>30</code></td>
 681         </tr>
 682         <tr>
 683           <td><strong>xAxisLabelWidth</strong></td>
 684           <td rowspan="2"><code>integer</code></td>
 685           <td><code></code></td>
 686           <td rowspan="2">Width (in pixels) of the x- and y-axis labels.
 687           <div class="tests">Tests: <a href="tests/customLabel.html">customLabel</a> </div>
 688           </td>
 689         </tr>
 690         <tr>
 691           <td><strong>yAxisLabelWidth</strong></td>
 692           <td><code></code></td>
 693         </tr>
 694         <tr>
 695           <td><strong>axisLabelFontSize</strong></td>
 696           <td><code>integer</code></td>
 697           <td><code>14</code></td>
 698           <td>Size of the font (in pixels) to use in the axis labels, both x- and y-axis.
 699           <div class="tests">Tests: <font color=red>none</font></div>
 700           </td>
 701         </tr>
 702         <tr>
 703           <td><strong>xAxisLabelFormatter</strong></td>
 704           <td><code>function(date, granularity)</code></td>
 705           <td><code>Dygraph.dateAxisFormatter</code></td>
 706           <td>Function to call to format values along the x axis.
 707             <div class="tests">Tests: <a href="tests/x-axis-formatter.html">xAxisLabelFormatter</a></div>
 708           </td>
 709         <tr>
 710           <td><strong>rightGap</strong></td>
 711           <td><code>integer</code></td>
 712           <td><code></code></td>
 713           <td>Number of pixels to leave blank at the right edge of the Dygraph. This makes it easier to highlight the right-most data point.
 714           <div class="tests">Tests: <font color=red>none</font></div>
 715           </td>
 716         </tr>
 717         <tr>
 718           <td><strong>errorBars</strong></td>
 719           <td><code>boolean</code></td>
 720           <td><code>false</code></td>
 721           <td>Does the data contain standard deviations? Setting this to true alters the input format (see above).
 722           <div class="tests">Tests: <a href="tests/noise.html">noise</a> <a href="tests/customLabel.html">customLabel</a> <a href="tests/draw-points.html">draw-points</a> <a href="tests/fillGraph.html">fillGraph</a> <a href="tests/fractions.html">fractions</a> </div>
 723           </td>
 724         </tr>
 725         <tr>
 726           <td><strong>sigma</strong></td>
 727           <td><code>integer</code></td>
 728           <td><code></code></td>
 729           <td>When errorBars is set, shade this many standard deviations above/below each point.
 730           <div class="tests">Tests: <font color=red>none</font></div>
 731           </td>
 732         </tr>
 733         <tr>
 734           <td><strong>fractions</strong></td>
 735           <td><code>boolean</code></td>
 736           <td><code>false</code></td>
 737           <td>When set, attempt to parse each cell in the CSV file as "a/b", where a and b are integers. The ratio will be plotted. This allows computation of Wilson confidence intervals (see below).
 738           <div class="tests">Tests: <a href="tests/fractions.html">fractions</a> </div>
 739           </td>
 740         </tr>
 741         <tr>
 742           <td><strong>wilsonInterval</strong></td>
 743           <td><code>boolean</code></td>
 744           <td><code>true</code></td>
 745           <td>Use in conjunction with the "fractions" option. Instead of plotting +/- N standard deviations, dygraphs will compute a Wilson confidence interval and plot that. This has more reasonable behavior for ratios close to 0 or 1.
 746           <div class="tests">Tests: <font color=red>none</font></div>
 747           </td>
 748         </tr>
 749         <tr>
 750           <td><strong>customBars</strong></td>
 751           <td><code>boolean</code></td>
 752           <td><code>false</code></td>
 753           <td>When set, parse each CSV cell as "low;middle;high". Error bars will be drawn for each point between low and high, with the series itself going through middle.
 754           <div class="tests">Tests: <a href="tests/custom-bars.html">custom-bars</a> <a href="tests/zero-series.html">zero-series</a> </div>
 755           </td>
 756         </tr>
 757
 758         <tr>
 759           <td><strong>drawCallback</strong></td>
 760           <td><code>function(dygraph, is_initial)</code></td>
 761           <td><code>null</code></td>
 762           <td>When set, this callback gets called every time the dygraph is drawn. This includes the initial draw, after zooming and repeatedly while panning. The first parameter is the dygraph being drawn. The second is a boolean value indicating whether this is the initial draw.
 763           <div class="tests">Tests: <a href="tests/callback.html">callback</a> <a href="tests/synchronize.html">synchronize</a> </div>
 764           </td>
 765         </tr>
 766
 767         <tr>
 768           <td><strong>gridLineColor</strong></td>
 769           <td><code>red, blue</code></td>
 770           <td><code>rgb(128,128,128)</code></td>
 771           <td>The color of the gridlines.
 772           <div class="tests">Tests: <a href="tests/grid_dot.html">grid_dot</a> </div>
 773           </td>
 774         </tr>
 775
 776         <tr>
 777           <td><strong>highlightCallback</strong></td>
 778           <td><code>function(event, x, points)</code></td>
 779           <td><code>null</code></td>
 780           <td>When set, this callback gets called every time a new point is highlighted. The parameters are the JavaScript mousemove event, the x-coordinate of the highlighted points and an array of highlighted points: <code>[ {name: 'series', yval: y-value}, &hellip; ]</code>
 781           <div class="tests">Tests: <a href="tests/callback.html">callback</a> <a href="tests/crosshair.html">crosshair</a> </div>
 782           </td>
 783         </tr>
 784
 785         <tr>
 786           <td><strong>unhighlightCallback</strong></td>
 787           <td><code>function(event)</code></td>
 788           <td><code>null</code></td>
 789           <td>When set, this callback gets called every time the user stops highlighting any point by mousing out of the graph.  The parameter is the mouseout event.
 790             <div class="tests">Tests: <a href="tests/callback.html">callback</a> <a href="tests/crosshair.html">crosshair</a> </div>
 791           </td>
 792         </tr>
 793
 794         <tr>
 795           <td><strong>strokeWidth</strong></td>
 796           <td><code>0.5, 2.0</code></td>
 797           <td><code>1.0</code></td>
 798           <td>The width of the lines connecting data points.
 799           <div class="tests">Tests: <a href="tests/grid_dot.html">grid_dot</a> </div>
 800           </td>
 801         </tr>
 802
 803         <tr>
 804           <td><strong>width</strong></td>
 805           <td rowspan="2"><code>integer</code></td>
 806           <td><code>480</code></td>
 807           <td rowspan="2">Width/Height (in pixels) of the chart. If the container div has been explicitly sized, these attributes will be ignored.
 808           <div class="tests">Tests: <a href="tests/demo.html">demo</a> <a href="tests/link-interaction.html">link-interaction</a> <a href="tests/no-range.html">no-range</a> </div>
 809           </td>
 810         </tr>
 811         <tr>
 812           <td><strong>height</strong></td>
 813           <td><code>320</code></td>
 814         </tr>
 815
 816       </tbody>
 817     </table>
 818
 819     <h2>Common Gotchas</h2>
 820
 821     <p>Here are a few problems that I've frequently run into while using the dygraphs library.</p>
 822
 823     <ul>
 824       <li>If your chart doesn't display, be sure to check your browser's JavaScript error console. dygraphs makes every attempt to log errors and warnings, and these can often guide you in the right direction.</li>
 825       <li>Make sure your CSV files are readable! If your graph isn't showing up, the XMLHttpRequest for the CSV file may be failing. You can determine whether this is the case using tools like <a href="http://www.getfirebug.com/">Firebug</a>.</li>
 826       <li>Make sure your CSV files are in the correct format. They must be of the form <code>YYYYMMDD, series1, series2, </code>&hellip; . And if you set the <code>errorBars</code> property, make sure you alternate data series and standard deviations.</li>
 827       <li>dygraphs are not happy when placed inside a <code>&lt;center&gt;</code> tag. This applies to the CSS <code>text-align</code> property as well. If you want to center a Dygraph, put it inside a table with <code>align = center</code> set.</li>
 828       <li>Don't set the <code>dateWindow</code> property to a date. It expects milliseconds since epoch, which can be obtained from a JavaScript Date object's valueOf method.</li>
 829       <li>Make sure you don't have any trailing commas in your call to the Dygraph constructor or in the options parameter. Firefox, Chrome and Safari ignore these but they can cause a graph to not display in Internet Explorer.</li>
 830     </ul>
 831
 832     <h2 id="gwt">GWT Compatibility</h2>
 833     <p>There is currently no GWT wrapper around Dygraphs, however there is a class that can be used to easily load Dygraphs into the browser.  To use it, include the generated dygraph-gwt.jar file in your classpath and add the following line to your GWT module:</p>
 834
 835 <pre>
 836 &lt;inherits name=&quot;org.danvk.dygraphs&quot;/&gt;
 837 </pre>
 838
 839     <p>Call org.danvk.Dygraphs.install() when your application starts to install the JavaScript code into the browser.  You can use <a href="http://code.google.com/webtoolkit/doc/latest/DevGuideCodingBasicsJSNI.html">JSNI</a> to call Dygraphs from your GWT code, as in the example below.  The example uses the <a href="http://code.google.com/p/gwt-google-apis/wiki/VisualizationGettingStarted">Visualization API for GWT</a> and the <a href="#gviz">Dygraphs GViz API.</a></p>
 840
 841 <pre>
 842   public static native JavaScriptObject drawDygraph(Element element, DataTable data, double minY, double maxY) /*-{
 843     var chart = new $wnd.Dygraph.GVizChart(element);
 844     chart.draw(dataTable,
 845       {
 846         valueRange: [minY, maxY]
 847       });
 848     return chart;
 849   }-*/;
 850 </pre>
 851
 852     <h2 id="policy">Data Policy</h2>
 853     <p>dygraphs is purely client-side JavaScript. It does not send your data to any servers &ndash; the data is processed entirely in the client's browser.</p>
 854
 855     <p style="font-size:0.8em">Created May 9, 2008 by <a href=mailto:danvdk@gmail.com>Dan Vanderkam</a></p>
 856   </div>
 857
 858
 859   <!-- Google Analytics -->
 860   <script src="http://www.google-analytics.com/urchin.js" type="text/javascript"></script>
 861   <script type="text/javascript">_uacct = "UA-769809-1";urchinTracker();</script>
 862 </body>
 863 </html>