Add axis_labels tests that rely on the preferred style of formatting axes.
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29 <div id="nav">
30 <h2>Documentation</h2>
31 <ul>
32 <li><a href="#demo">Demo</a></li>
33 <li><a href="#usage">Usage</a></li>
34 <li><a href="#ie">IE Compatibility</a></li>
35 <li><a href="#gviz">GViz Data</a></li>
36 <li><a href="#baseball">Baseball chart</a></li>
37 <li><a href="#stock">Stock chart</a></li>
38 <li><a href="#gwt">GWT Compatibility</a></li>
39 <li><a href="#policy">Data Policy</a></li>
40 <li><a href="options.html">Options Reference</a></li>
41 <li><a href="jsdoc/symbols/Dygraph.html">JSDoc Reference</a></li>
42 <li><a href="data.html">Data Formats</a></li>
43 <li><a href="annotations.html">Annotations</a></li>
44 </ul>
45
46 <h2>Project</h2>
47 <ul>
48 <li><a href="http://blog.dygraphs.com/">Blog</a></li>
49 <li><a href="http://github.com/danvk/dygraphs">Source</a></li>
50 <li><a href="http://code.google.com/p/dygraphs/issues/">Issues</a></li>
51 <li><a href="http://code.google.com/p/dygraphs/issues/entry">Report Bug</a></li>
52 <li><a href="changes.html">Contribute a change</a></li>
53 <li><a href="mailto:dygraphs-users [at] googlegroups.com">Contact</a></li>
54 </ul>
55
56 <h2>Demos/Usage</h2>
57 <ul>
58 <li><a href="#users">Known Users</a></li>
59 <hr/>
60 <li><span style="color: red;">New!</span> <a href="gallery/">(browse gallery)</a></li>
61 <li><a href="tests/">(browse demos)</a></li>
62 <li><a href="tests/demo.html">Basic Demo</a></li>
63 <li><a href="tests/gviz.html">GViz Demo</a></li>
64 <li><a href="tests/plotter.html">Equation Plotter</a></li>
65 <li><a href="tests/perf.html">Performance Test</a></li>
66 <li><a href="tests/annotation.html">Annotations</a></li>
67 <li><a href="tests/annotation-gviz.html">Annotations (GViz)</a></li>
68 <li><a href="tests/fillGraph.html">Filled Chart</a></li>
69 <li><a href="tests/perf.html">Fractions</a></li>
70 <li><a href="tests/visibility.html">Visibility</a></li>
71 <li><a href="tests/label-div.html">Labels in a DIV</a></li>
72 <li><a href="tests/numeric-axis.html">Numeric Axis</a></li>
73 <li><a href="tests/draw-points.html">Dotted Points</a></li>
74 <li><a href="tests/native-format.html">Native Format</a></li>
75 <li><a href="tests/grid_dot.html">Crazy Styles</a></li>
76 <li><a href="tests/spacing.html">Tick spacing</a></li>
77 <li><a href="tests/callback.html">Callbacks</a></li>
78 <li><a href="tests/hourly.html">Hourly/Minutely data</a></li>
79 <li><a href="tests/isolated-points.html">Isolated Points</a></li>
80 <li><a href="tests/missing-data.html">Missing Data</a></li>
81 <li><a href="tests/border.html">Bordered chart</a></li>
82 <li><a href="tests/custom-bars.html">Custom Bars</a></li>
83 <li><a href="tests/customLabel.html">Custom Label Styles</a></li>
84 <li><a href="tests/dygraph.html">Minimal Example</a></li>
85 <li><a href="tests/negative.html">Negative Numbers</a></li>
86 <li><a href="tests/highlighted-region.html">Custom Underlay / background</a></li>
87 <li><a href="tests/zoom.html">Tests for zoom operations</a></li>
88 <li><a href="tests/logscale.html">Log scale tests</a></li>
89 </ul>
90 </div>
91
92 <div id="content">
93 <h1>dygraphs JavaScript Visualization Library</h1>
94
95 <p><a href="http://github.com/danvk/dygraphs">http://github.com/danvk/dygraphs</a></p>
96 <p>See <a href="http://blog.dygraphs.com/">blog</a>, <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/">demos</a> and <a href="http://code.google.com/p/dygraphs/issues/">open issues</a></p>
97
98 <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>
99
100 <h3 id="demo">A demo is worth a thousand words:</h3>
101
102 <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>
103
104 <div id="demodiv" style="width:800px; height:320px;"></div>
105 <script type="text/javascript">
106 g = new Dygraph(
107 document.getElementById("demodiv"),
108 "ny-vs-sf.txt",
109 {
110 rollPeriod: 14,
111 showRoller: true,
112 customBars: true,
113 title: 'Daily Temperatures in New York vs. San Francisco',
114 ylabel: 'Temperature (F)',
115 legend: 'always',
116 labelsDivStyles: { 'textAlign': 'right' }
117 }
118 );
119 </script>
120
121 <h4>Some things to notice:</h4>
122 <ul>
123 <li>There's less seasonal temperature variation in SF than in NY.</li>
124 <li>The difference is about 15&deg; F for SF vs. 50&deg; F for NY.</li>
125 <li>The daily data (set rolling period to 1) is quite noisy and hides this conclusion.</li>
126 <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>
127 <li>There's a gap in the data for SF, when the weather station was down (zoom into October 2007 to see it).</li>
128 <li>The bands around each point indicate average highs and lows.</li>
129 <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>
130 </ul>
131
132 <p>dygraphs allows the user to explore the data and discover these facts.</p>
133
134 <p>For more demos, browse the dygraph <a href="tests/">tests</a>
135 directory. To see other people who are using dygraphs, check out the <a
136 href="#users">known users</a>.</p>
137
138 <h3>Features</h3>
139 <p>Some of the features of dygraphs:</p>
140 <ul>
141 <li>Plots time series without using an external server or Flash</li>
142 <li>Works in Internet Explorer (using excanvas)</li>
143 <li>Lightweight (69kb) and responsive</li>
144 <li>Displays values on mouseover, making interaction easily discoverable</li>
145 <li>Supports error bands around data series</li>
146 <li>Interactive zoom</li>
147 <li>Displays Annotations on the chart</li>
148 <li>Adjustable averaging period</li>
149 <li>Can intelligently chart fractions</li>
150 <li>Customizable click-through actions</li>
151 <li>Compatible with the Google Visualization API</li>
152 <li>Intelligent defaults make it easy to use</li>
153 </ul>
154
155 <h2 id="usage">Usage</h2>
156
157 <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>
158
159 <p>Here's a basic example to get things started:</p>
160
161 <div class="example" style="clear:both;">
162 <div class="codeblock" style="float:left;width:400px;">
163 <h3 style="text-align:center">HTML</h3>
164 <code>
165 <pre>
166 &lt;html&gt;
167 &lt;head&gt;
168 &lt;script type=&quot;text/javascript&quot;
169 src=&quot;dygraph-combined.js&quot;&gt;&lt;/script&gt;
170 &lt;/head&gt;
171 &lt;body&gt;
172 &lt;div id=&quot;graphdiv&quot;&gt;&lt;/div&gt;
173 &lt;script type=&quot;text/javascript&quot;&gt;
174 g = new Dygraph(
175
176 // containing div
177 document.getElementById(&quot;graphdiv&quot;),
178
179 // CSV or path to a CSV file.
180 &quot;Date,Temperature\n&quot; +
181 &quot;2008-05-07,75\n&quot; +
182 &quot;2008-05-08,70\n&quot; +
183 &quot;2008-05-09,80\n&quot;
184
185 );
186 &lt;/script&gt;
187 &lt;/body&gt;
188 &lt;/html&gt;
189 </pre>
190 </code>
191 </div>
192 <div class="codeoutput" style="float:left;">
193 <h3 style="text-align:center">OUTPUT</h3>
194 <div id="graphdiv"></div>
195 <script type="text/javascript">
196 g = new Dygraph(
197
198 // containing div
199 document.getElementById("graphdiv"),
200
201 // CSV or path to a CSV file.
202 "Date,Temperature\n" +
203 "2008-05-07,75\n" +
204 "2008-05-08,70\n" +
205 "2008-05-09,80\n"
206 );
207 </script>
208 </div>
209 </div>
210
211 <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>
212
213 <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>
214
215 <div class="example" style="clear:both;">
216 <div class="codeblock" style="float:left;width:400px;">
217 <h3 style="text-align:center">HTML</h3>
218 <code>
219 <pre>
220 &lt;html&gt;
221 &lt;head&gt;
222 &lt;script type=&quot;text/javascript&quot;
223 src=&quot;dygraph-combined.js&quot;&gt;&lt;/script&gt;
224 &lt;/head&gt;
225 &lt;body&gt;
226 &lt;div id=&quot;graphdiv2&quot;
227 style=&quot;width:500px; height:300px;&quot;&gt;&lt;/div&gt;
228 &lt;script type=&quot;text/javascript&quot;&gt;
229 g2 = new Dygraph(
230 document.getElementById(&quot;graphdiv2&quot;),
231 &quot;temperatures.csv&quot;, // path to CSV file
232 {} // options
233 );
234 &lt;/script&gt;
235 &lt;/body&gt;
236 &lt;/html&gt;
237 </pre>
238 </code>
239 </div>
240 <div class="codeoutput" style="float:left;">
241 <h3 style="text-align:center">OUTPUT</h3>
242 <div id="graphdiv2" style="width:500px; height:300px;"></div>
243 <script type="text/javascript">
244 g2 = new Dygraph(
245 document.getElementById("graphdiv2"),
246 "temperatures.csv",
247 {}
248 );
249 </script>
250 </div>
251 </div>
252
253 <p style="clear:both;">The file used is <code><a href="temperatures.csv">temperatures.csv</a></code>.</p>
254
255 <p>There are a few things to note here:</p>
256
257 <ul>
258 <li>The Dygraph sent off an XHR to get the temperatures.csv file.</li>
259 <li>The labels were taken from the first line of <code>temperatures.csv</code>, which is <code>Date,High,Low</code>.</li>
260 <li>The Dygraph automatically chose two different, easily-distinguishable colors for the two data series.</li>
261 <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>
262 <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>
263 <li>The data is very spiky. A moving average would be easier to interpret.</li>
264 </ul>
265
266 <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>
267
268 <div class="example" style="clear:both;">
269 <div class="codeblock" style="float:left;width:400px;">
270 <h3 style="text-align:center">HTML</h3>
271 <code>
272 <pre>
273 &lt;html&gt;
274 &lt;head&gt;
275 &lt;script type=&quot;text/javascript&quot;
276 src=&quot;dygraph-combined.js&quot;&gt;&lt;/script&gt;
277 &lt;/head&gt;
278 &lt;body&gt;
279 &lt;div id=&quot;graphdiv3&quot;
280 style=&quot;width:500px; height:300px;&quot;&gt;&lt;/div&gt;
281 &lt;script type=&quot;text/javascript&quot;&gt;
282 g3 = new Dygraph(
283 document.getElementById(&quot;graphdiv3&quot;),
284 &quot;temperatures.csv&quot;,
285 {
286 rollPeriod: 7,
287 showRoller: true
288 }
289 );
290 &lt;/script&gt;
291 &lt;/body&gt;
292 &lt;/html&gt;
293 </pre>
294 </code>
295 </div>
296 <div class="codeoutput" style="float:left;">
297 <h3 style="text-align:center">OUTPUT</h3>
298 <div id="graphdiv3" style="width:500px; height:300px;"></div>
299 <script type="text/javascript">
300 g3 = new Dygraph(
301 document.getElementById("graphdiv3"),
302 "temperatures.csv",
303 {
304 rollPeriod: 7,
305 showRoller: true
306 }
307 );
308 </script>
309 </div>
310 </div>
311
312 <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>
313
314 <h2>Error Bars</h2>
315
316 <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>
317
318 <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>
319
320 <div class="example" style="clear:both;">
321 <div class="codeblock" style="float:left;width:400px;">
322 <h3 style="text-align:center">HTML</h3>
323 <code>
324 <pre>
325 &lt;html&gt;
326 &lt;head&gt;
327 &lt;script type=&quot;text/javascript&quot;
328 src=&quot;combined.js&quot;&gt;&lt;/script&gt;
329 &lt;/head&gt;
330 &lt;body&gt;
331 &lt;div id=&quot;graphdiv4&quot;
332 style=&quot;width:480px; height:320px;&quot;&gt;&lt;/div&gt;
333 &lt;script type=&quot;text/javascript&quot;&gt;
334 g4 = new Dygraph(
335 document.getElementById(&quot;graphdiv4&quot;),
336 &quot;twonormals.csv&quot;,
337 {
338 rollPeriod: 7,
339 showRoller: true,
340 errorBars: true,
341 valueRange: [50,125]
342 }
343 );
344 &lt;/script&gt;
345 &lt;/body&gt;
346 &lt;/html&gt;
347 </pre>
348 </code>
349 </div>
350 <div class="codeoutput" style="float:left;">
351 <h3 style="text-align:center">OUTPUT</h3>
352 <div id="graphdiv4" style="width:480px; height:320px;"></div>
353 <script type="text/javascript">
354 g4 = new Dygraph(
355 document.getElementById("graphdiv4"),
356 "twonormals.csv",
357 {
358 rollPeriod: 7,
359 showRoller: true,
360 errorBars: true,
361 valueRange: [50,125]
362 }
363 );
364 </script>
365 </div>
366 </div>
367
368 <p style="clear:both;">Things to note here:</p>
369
370 <ul>
371 <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>
372 <li>The first line of the CSV file doesn't mention the error columns. In this case, it's just "Date,Series1,Series2".</li>
373 <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>
374 <li>The error bars are partially transparent. This can be seen when they overlap one another.</li>
375 </ul>
376
377 <h2 id="ie">Internet Explorer Compatibility</h2>
378
379 <p>The dygraphs library relies heavily on the HTML5 <code>&lt;canvas&gt;</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>
380
381 <pre>
382 &lt;!DOCTYPE html&gt;
383 </pre>
384
385 <p>When IE9 is in HTML5 mode, dygraphs works just like in other modern browsers.</p>
386
387 <p>If you want to support previous versions of Internet Explorer (IE6&ndash;IE8), you'll need to include the <a href="http://code.google.com/p/explorercanvas/">excanvas</a> library, which emulates the <code>&lt;canvas&gt;</code> tag using VML. You can add excanvas by including the following snippet:</p>
388
389 <pre>
390 &lt;!DOCTYPE html&gt;
391 &lt;html&gt;
392 &lt;head&gt;
393 &lt;meta http-equiv="X-UA-Compatible" content="IE=EmulateIE7; IE=EmulateIE9"&gt;
394 &lt;!--[if IE]&gt;&lt;script src="path/to/excanvas.js"&gt;&lt;/script&gt;&lt;![endif]--&gt;
395 &lt;/head&gt;
396 </pre>
397
398 <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.)</p>
399
400 <p>While VML emulation sounds like it would be slow, it works well in practice for most charts.</p>
401
402 <p>One common gotcha to look out for: make sure you don't have any trailing commas in parameter lists, e.g.</p>
403
404 <pre>
405 new Dygraph(el, data, {
406 showRoller: true, // note trailing comma
407 })</pre>
408
409 <p>Most browsers will ignore the trailing comma, but it will break under IE.</p>
410
411 <h2 id="gviz">GViz Data</h2>
412
413 <p>The <a
414 href="http://code.google.com/apis/visualization/documentation/index.html">Google
415 Visualization API</a> provides a standard interface for describing data.
416 Once you've specified your data using this API, you can plug in any
417 GViz-compatible visualization. dygraphs is such a visualization. In
418 particular, it can be used as a drop-in replacement for the
419 AnnotatedTimeline visualization used on Google Finance and other sites. To
420 see how this works, check out the <a href="tests/annotation-gviz.html">gviz
421 annotation demo.</a></p>
422
423 <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>
424
425 <p>Here's an example of a published gviz gadget using dygraphs:</p>
426
427 <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>
428
429 <h2 id="baseball">Charting Fractions</h2>
430
431 <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>
432
433 <ul>
434 <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>
435 <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>
436 </ul>
437
438 <p>Fortunately, dygraphs handles both of these for you! Here's a chart and the command that generated it:</p>
439
440 <div style="width:750px; text-align:center; font-weight: bold; font-size: 125%;">Batting Average for Ichiro Suzuki vs. Mariners (2004)</div>
441 <div id="baseballdiv" style="width:750px; height:300px;"></div>
442 <script type="text/javascript">
443 new Dygraph(
444 document.getElementById("baseballdiv"),
445 "suzuki-mariners.txt",
446 {
447 fractions: true,
448 errorBars: true,
449 showRoller: true,
450 rollPeriod: 15
451 }
452 );
453 </script>
454
455 <p>Command:</p>
456 <pre>
457 new Dygraph(
458 document.getElementById(&quot;baseballdiv&quot;),
459 &quot;suzuki-mariners.txt&quot;,
460 {
461 fractions: true,
462 errorBars: true,
463 showRoller: true,
464 rollPeriod: 15
465 }
466 );
467 </pre>
468
469 <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>
470
471 <p>A couple things to notice about this chart:</p>
472
473 <ul>
474 <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>
475 <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>
476 <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>
477 <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>
478 </ul>
479
480 <h2 id="stock">One last demo</h2>
481
482 <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>
483
484 <div id="dow_chart" style="width:750px; height:350px;"></div>
485 <p><b>Display: </b>
486 <input type=checkbox id=0 onClick="stockchange(this)" checked>
487 <label for="0"> Nominal</label>
488 <input type=checkbox id=1 onClick="stockchange(this)" checked>
489 <label for="1"> Real</label>
490 <input type=checkbox id=ann onClick="annotationschange(this)" checked>
491 <label for="ann"> Annotations</label>
492 </p>
493
494 <script type="text/javascript">
495 var stock_annotations = [
496 {
497 series: "Real",
498 x: "1929-08-15",
499 shortText: "A",
500 text: "1929 Stock Market Peak"
501 },
502 {
503 series: "Nominal",
504 x: "1987-08-15",
505 shortText: "B",
506 text: "1987 Crash"
507 },
508 {
509 series: "Nominal",
510 x: "1999-12-15",
511 shortText: "C",
512 text: "1999 (.com) Peak"
513 },
514 {
515 series: "Nominal",
516 x: "2007-10-15",
517 shortText: "D",
518 text: "All-Time Market Peak"
519 }
520 ];
521
522 // From http://www.econstats.com/eqty/eq_d_mi_3.csv
523 stockchart = new Dygraph(
524 document.getElementById('dow_chart'),
525 "dow.txt",
526 {
527 showRoller: true,
528 customBars: true,
529 labelsKMB: true,
530 drawCallback: function(g, is_initial) {
531 if (!is_initial) return;
532 g.setAnnotations( stock_annotations );
533 }
534 }
535 );
536
537 function stockchange(el) {
538 stockchart.setVisibility(el.id, el.checked);
539 }
540
541 function annotationschange(el) {
542 if (el.checked) {
543 stockchart.setAnnotations(stock_annotations);
544 } else {
545 stockchart.setAnnotations([]);
546 }
547 }
548 </script>
549 <!--
550
551 Here is a script to regenerate the Dow Jones plot:
552
553 # Get unadjusted DJIA data in a nice format:
554 curl -O http://www.econstats.com/eqty/eq_d_mi_3.csv
555 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
556
557 # Fetch and format the CPI data:
558 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
559 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-$2\t/g' > cpi-u.tsv
560
561 # Merge:
562 join -t' ' cpi-u.tsv monthly-djia.tsv > annotated-djia.tsv
563 perl -ne 'BEGIN{print "Month,Nominal,Real\n"} chomp; ($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
564
565 -->
566
567 <h2 id="options">Other Options</h2>
568
569 <p>In addition to the options mentioned above (<code>showRoller</code>, <code>rollPeriod</code>, <code>errorBars</code>, <code>valueRange</code>), there are <i>many</i> others.</p>
570
571 <p>For a full list, see the <a href="options.html">Dygraphs Options Reference</a> page.</p>
572
573 <h2>Common Gotchas</h2>
574
575 <p>Here are a few problems that I've frequently run into while using the dygraphs library.</p>
576
577 <ul>
578 <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>
579 <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>
580 <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>
581 <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>
582 <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>
583 <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>
584 </ul>
585
586 <h2 id="gwt">GWT Compatibility</h2>
587 <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>
588
589 <pre>
590 &lt;inherits name=&quot;org.danvk.dygraphs&quot;/&gt;
591 </pre>
592
593 <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>
594
595 <pre>
596 public static native JavaScriptObject drawDygraph(
597 Element element, DataTable dataTable, double minY, double maxY) /*-{
598 var chart = new $wnd.Dygraph.GVizChart(element);
599 chart.draw(dataTable,
600 {
601 valueRange: [minY, maxY]
602 });
603 return chart;
604 }-*/;
605 </pre>
606
607 <a name="users" />
608 <h2>Known Users</h2>
609 <p>Since its public release in late 2009, dygraphs has found many users
610 across the web. This is a small collection of the uses that we know about.
611 If you're using dygraphs, please send <a
612 href="mailto:dan@dygraphs.com">Dan</a> a link and he'll add it to this
613 list.</p>
614
615 <p>dygraphs was originally developed at Google and has found wide use on
616 internal dashboards and servers there. There are also a few uses of
617 dygraphs on public Google products:</p>
618
619 <ul class='padded-list'>
620 <li><a href="http://www.google.com/trends/correlate/search?e=id:20xKcnNqHrk&t=weekly">Google Correlate</a><br/>
621 <span class="desc">Uses dygraphs for time series visualization. Mostly a standard configuration, with just a few tweaks to match Google style.</span></li>
622
623 <li><a href="http://www.google.com/trends/correlate/draw?p=us">Google Correlate - Search by Drawing</a><br/>
624 <span class="desc">This is a highly customized configuration which lets the user draw a time series. Based on <a href="tests/drawing.html">this demo</a>.</span></li>
625
626 <li><a href="https://www.google.com/latitude/b/0/history/manage">Google Latitude History Dashboard</a><br/>
627 <span class="desc">Uses mouse interaction callbacks to synchronize time series points with markers on a Google Map.</span></li>
628 </ul>
629
630 <p>dygraphs has also found use in other organizations:</p>
631
632 <ul class='padded-list'>
633 <li><a
634 href="http://iswa.ccmc.gsfc.nasa.gov:8080/IswaSystemWebApp/index.jsp?i_1=388&l_1=99&t_1=316&w_1=800&h_1=400&s_1=0!3!0!ACE.B_x!ACE.B_y!ACE.B_z!">Integrated
635 Space Weather Analysis System</a> (NASA)<br/>
636 <span class="desc">&ldquo;We use [dygraphs] in the Integrated Space Weather
637 Analysis System available from the Space Weather Laboratory at NASA Goddard
638 Space Flight Center. It works quite well for time series data from various
639 missions and simulations that we store.&rdquo;</span></li>
640
641
642 <li><a href="http://www.eutelsat.fr">Eutelsat</a><br/>
643 <span class="desc">&ldquo;Eutelsat uses dygraphs for charting spacecraft
644 telemetry for a fleet of 25 geostationary satellites. The spacecraft
645 engineers are very happy with it. All satellite combined are producing
646 about 200 millions unique data points per day so we really appreciate the
647 excellent performance of dygraphs.&rdquo;</span></li>
648
649 <li><a href="http://www.10gen.com/mongodb-monitoring-service">10gen MongoDB
650 Monitoring Service</a><br/>
651 <span class="desc">A free monitoring service for MongoDB from 10gen (the
652 creators of MongoDB). Used by thousands of servers and users. Makes use of
653 <a href="tests/synchronize.html">synchronized charts</a> to display many
654 quantities simultaneously.</span></li>
655
656 <li><a href="http://duckduckgo.com/traffic.html">Duck Duck Go Traffic Dashboard</a><br/>
657 <span class="desc">DDG uses dygraphs to display a public chart of their daily traffic. They use annotations and the moving average features.</span></li>
658
659 <li><a href="http://toolserver.org/~dartar/moodbar/">Wikimedia Foundation - Moodbar data dashboard</a><br/>
660 <span class="desc">dygraphs is used internally at Wikimedia as a handy solution to monitor the
661 results of a bunch of small experiments.</span></li>
662
663 <li><a href="http://code.google.com/p/quadrant-framework/">quadrant-framework</a> (MySQL Load Testing Framework)<br/>
664 <span class="desc">A user friendly framework for creating and visualizing
665 MySQL database load test jobs. For more information on its use of dygraphs,
666 see <a href="http://themattreid.com/wordpress/2011/05/20/quadrant-framework-rev7-update-adds-dygraphs-support/">this post</a>.</span></li>
667
668 <li><a href="http://spinwave.wordpress.com/2011/03/28/spinwave-systems-enables-energy-efficiency-case-studies/">Spinwave Systems</a> (Home energy monitoring)<br/>
669 <span class="desc">dygraphs is used to chart energy usage over time.</span></li>
670
671
672 <li><a href="http://www.socib.es/jwebchart/?file=http://thredds.socib.es/thredds/dodsC/mooring/weather_station/mobims_calamillor-scb_met001/L1/dep0001_mobims-calamillor_scb-met001_L1_latest.nc">Jwebchart</a><br/>
673 <span class="desc">
674 jWebChart is a stand-alone and Thredds' embedded plotting system for
675 netCDF files. NetCDF is a common standard for the storage and
676 distribution of scientific data.
677 </span></li>
678
679 <li><a href="http://ngrams.cavorite.com/">n-gramas - Explore las tendencias en los artículos periodísticos de Colombia.</a><br/>
680
681
682 <span class="desc">(English: "Explore trends in newspaper articles of
683 Colombia"). dygraphs is used for displaying the results of this n-grams
684 viewer. Uses an extension for exporting the plots as PNG images
685 (<a href="http://cavorite.com/labs/js/dygraphs-export/">[1]</a>, <a href="https://github.com/cavorite/dygraphs">[2]</a>).
686 </span></li>
687
688 </ul>
689
690 <p>Are you using dygraphs? Please let <a href="mailto:dan@dygraphs.com">Dan</a> know and he'll add your link here!</p>
691
692
693 <h2 id="policy">Data Policy</h2>
694 <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>
695
696 <p style="font-size:0.8em">Created May 9, 2008 by <a href=mailto:danvdk@gmail.com>Dan Vanderkam</a></p>
697 </div>
698
699 </body>
700 </html>