- <h2 id="ie">Internet Explorer Compatibility</h2>
-
- <p>The dygraphs library relies heavily on HTML's <code><canvas></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><canvas></code> tag in IE using VML.</p>
-
- <p>You can add IE support to any page using dygraphs by including the following in your page:</p>
-
-<pre>
-<head>
- <!--[if IE]><script src="excanvas.js"></script><![endif]-->
-</head>
-</pre>
-
- <p>This works quite well in practice. Charts are responsive, even under VML emulation.</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>
-
- <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:900px; 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 );
- }
- }
- );
-
- function stockchange(el) {
- stockchart.setVisibility(el.id, el.checked);
- }
-
- function annotationschange(el) {
- if (el.checked) {
- stockchart.setAnnotations(stock_annotations);
- } else {
- stockchart.setAnnotations([]);
- }
- }
- </script>
-<!--
-
-Here is a script to regenerate the Dow Jones plot:
-
-# Get unadjusted DJIA data in a nice format:
-curl -O http://www.econstats.com/eqty/eq_d_mi_3.csv
-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
-
-# Fetch and format the CPI data:
-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
-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-$2\t/g' > cpi-u.tsv
-
-# Merge:
-join -t' ' cpi-u.tsv monthly-djia.tsv > annotated-djia.tsv
-perl -ne 'BEGIN{print "Month,Nominal,Real\n"} chomp; ($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
-
--->
-
- <h2 id="options">Other Options</h2>
-
- <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>
-
- <p>For a full list, see the <a href="options.html">Dygraphs Options Reference</a> page.</p>
-
- <h2>Common Gotchas</h2>
-
- <p>Here are a few problems that I've frequently run into while using the dygraphs library.</p>
-
- <ul>
- <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>
- <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>
- <li>Make sure your CSV files are in the correct format. They must be of the form <code>YYYYMMDD, series1, series2, </code>… . And if you set the <code>errorBars</code> property, make sure you alternate data series and standard deviations.</li>
- <li>dygraphs are not happy when placed inside a <code><center></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>
- <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>
- <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>
- </ul>
-
- <h2 id="gwt">GWT Compatibility</h2>
- <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>
-
-<pre>
-<inherits name="org.danvk.dygraphs"/>
-</pre>
-
- <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>
-
-<pre>
- public static native JavaScriptObject drawDygraph(Element element, DataTable dataTable, double minY, double maxY) /*-{
- var chart = new $wnd.Dygraph.GVizChart(element);
- chart.draw(dataTable,
- {
- valueRange: [minY, maxY]
- });
- return chart;
- }-*/;
-</pre>
-
- <h2 id="policy">Data Policy</h2>
- <p>dygraphs is purely client-side JavaScript. It does not send your data to any servers – the data is processed entirely in the client's browser.</p>
-
- <p style="font-size:0.8em">Created May 9, 2008 by <a href=mailto:danvdk@gmail.com>Dan Vanderkam</a></p>