+ rollPeriod: 15
+ }
+ );
+</pre>
+
+ <p>The <code>fractions</code> option indicates that the values in each column should be parsed as fractions (e.g. "1/2" instead of "0.5"). The <code>errorBars</code> option indicates that we'd like to see a confidence interval around each data point. By default, when <code>fractions</code> is set, you get a Wilson confidence interval. If you look carefully at the chart, you can see that the error bars are asymmetric.</p>
+
+ <p>A couple things to notice about this chart:</p>
+
+ <ul>
+ <li>The error bars for Ichiro's batting average are larger than for the Mariners', since he has far fewer at bats than his team.</li>
+ <li>dygraphs makes it easy to see "batting average over the last 30 games". This is ordinarily quite difficult to compute. It makes it clear where the "hot" and "cold" part of Suzuki's season were.</li>
+ <li>If you set the averaging period to something large, like 200, you'll see the team's and player's batting average through that game. The final number is the overall batting average for the season.</li>
+ <li>Where the error bars do not overlap, we can say with 95% confidence that the series differ. There is a better than 95% chance that Ichiro was a better hitter than his team as a whole in 2004, the year he won the batting title.</li>
+ </ul>
+
+ <h2 id="stock">One last demo</h2>
+
+ <p>This chart shows monthly closes of the Dow Jones Industrial Average, both in nominal and real (i.e. adjusted for inflation) dollars. The shaded areas show its monthly high and low. CPI values with a base from 1982-84 are used to adjust for inflation.</p>
+
+ <div id="dow_chart" style="width:750px; height:350px;"></div>
+ <p><b>Display: </b>
+ <input type=checkbox id=0 onClick="stockchange(this)" checked>
+ <label for="0"> Nominal</label>
+ <input type=checkbox id=1 onClick="stockchange(this)" checked>
+ <label for="1"> Real</label>
+ <input type=checkbox id=ann onClick="annotationschange(this)" checked>
+ <label for="ann"> Annotations</label>
+ </p>
+
+ <script type="text/javascript">
+ var stock_annotations = [
+ {
+ series: "Real",
+ x: "1929-08-15",
+ shortText: "A",
+ text: "1929 Stock Market Peak"
+ },
+ {
+ series: "Nominal",
+ x: "1987-08-15",
+ shortText: "B",
+ text: "1987 Crash"
+ },
+ {
+ series: "Nominal",
+ x: "1999-12-15",
+ shortText: "C",
+ text: "1999 (.com) Peak"
+ },
+ {
+ series: "Nominal",
+ x: "2007-10-15",
+ shortText: "D",
+ text: "All-Time Market Peak"
+ }
+ ];
+
+ // From http://www.econstats.com/eqty/eq_d_mi_3.csv
+ stockchart = new Dygraph(
+ document.getElementById('dow_chart'),
+ "dow.txt",
+ {
+ showRoller: true,
+ customBars: true,
+ labelsKMB: true,
+ drawCallback: function(g, is_initial) {
+ if (!is_initial) return;
+ g.setAnnotations( stock_annotations );
+ }
+ }
+ );
+
+ 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]