X-Git-Url: https://adrianiainlam.tk/git/?a=blobdiff_plain;f=docs%2Findex.html;h=a4fb76c1c951b9bf3c251c3767f689fa2b1d96c9;hb=7ca60bd1161dc1e4c623fb9def484fa20854149c;hp=cb4f362778fd122b6cf538bb30d10328045bb8be;hpb=bb89f4463bfe972067bd9894421a98ed0563292c;p=dygraphs.git diff --git a/docs/index.html b/docs/index.html index cb4f362..a4fb76c 100644 --- a/docs/index.html +++ b/docs/index.html @@ -1,6 +1,6 @@ - dygraphs JavaScript Library + dygraphs JavaScript Visualization Library @@ -19,82 +19,155 @@ border-style: solid; border-color: black; } + + #nav { + position: absolute; + left: 0px; + width: 150px; + } + #content { + position: absolute; + left: 160px; + top: 0px; + border-left: 2px solid rgb(229, 236, 249); + padding-left: 10px; + margin-left: 0px; + } + + #nav ul { + list-style: none; + padding-left: 20px; + margin-left: 0px; + } + #nav ul ul { + padding-left: 0.5em; + padding-bottom: 1em; + } + #nav ul ul li { + padding-top: 0.25em; + } -
-

dygraphs JavaScript Library
- code.google.com/p/dygraphs

-
- -

The dygraphs JavaScript library produces produces interactive, zoomable charts of time series.

-

Features

+ -

Caveats

- +
+

dygraphs JavaScript Visualization Library
+http://github.com/danvk/dygraphs
+See downloads, gallery and open issues

-

Demo

-(Mouse over to highlight individual values. Click and drag to zoom. Double-click to zoom out.)
- -
-
-		 -
-
+

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.

+ + +

A demo is worth a thousand words:

+ +

(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.)

+
Temperatures in New York vs. San Francisco
+
+

Some things to notice:

+ + +

dygraphs allows the user to explore the data and discover these facts.

+

For more demos, browse the dygraph tests directory.

-

Usage

+

Features

+

Some of the features of dygraphs:

+ -

The dygraphs library depends on two other JS libraries: MochiKit and PlotKit. Rather than tracking down copies of these libraries, I recommend using a packed version of dygraphs that combines all three libraries into a single JS file. Either grab this file from dygraph project's downloads page or create it yourself by checking out a copy of the code and running: +

Usage

-
./generate-combined.sh
+

To use dygraphs, include the dygraph-combined.js JavaScript file and instantiate a Dygraph object.

-

The combined JS file is now in dygraph-combined.js. Here's a basic example to get things started:

+

Here's a basic example to get things started:

@@ -104,17 +177,20 @@
HTML
 <html>
 <head>
-<script type="text/javascript" src="combined.js"></script>
+<script type="text/javascript"
+  src="dygraph-combined.js"></script>
 </head>
 <body>
 <div id="graphdiv"></div>
 <script type="text/javascript">
   g = new Dygraph(
-        document.getElementById("graphdiv"),  // containing div
-        "Date,Temperature\n" +                // CSV or path to a CSV file.
-        "20080507,75\n" +
-        "20080508,70\n" +
-        "20080509,80\n",
+        // containing div
+        document.getElementById("graphdiv"),
+        // CSV or path to a CSV file.
+        "Date,Temperature\n" +
+        "2008-05-07,75\n" +
+        "2008-05-08,70\n" +
+        "2008-05-09,80\n"
       );
 </script>
 </body>
@@ -122,18 +198,21 @@
-
-

In order to keep this example self-contained, the second parameter is a function that returns CSV data. These lines must begin with a date in the form YYYYMMDD. In most applications, it makes more sense to include a CSV file instead. If the second parameter to the constructor is a string, 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 "file:///". Here's an example: (data from Weather Underground)

+ + +

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 the its container to a reasonable default, calculates appropriate axis ranges and tick marks and draws the graph.

+ +

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 "file:///". Here's an example: (data from Weather Underground)

@@ -143,30 +222,33 @@
HTML
 <html>
 <head>
-<script type="text/javascript" src="combined.js"></script>
+<script type="text/javascript"
+  src="dygraph-combined.js"></script>
 </head>
 <body>
-<div id="graphdiv" style="width:600px; height:300px;"></div>
+<div id="graphdiv"
+  style="width:500px; height:300px;"></div>
 <script type="text/javascript">
-  g = new Dygraph(
-        document.getElementById("graphdiv"),
-        "temperatures.csv",  // path to CSV file
-        {}                   // additional options
-      );
+  new Dygraph(
+    document.getElementById("graphdiv"),
+    "temperatures.csv",  // path to CSV file
+    {}                   // options
+  );
 </script>
 </body>
 </html>
-
- +
+ +

Click here to view the temperatures.csv file. There are a few things to note here:

-

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 rollPeriod option. Here's how it's done:

+

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 rollPeriod option. Here's how it's done:

@@ -188,10 +270,12 @@
HTML
 <html>
 <head>
-<script type="text/javascript" src="combined.js"></script>
+<script type="text/javascript"
+  src="dygraph-combined.js"></script>
 </head>
 <body>
-<div id="graphdiv" style="width:600px; height:300px;"></div>
+<div id="graphdiv"
+  style="width:500px; height:300px;"></div>
 <script type="text/javascript">
   g = new Dygraph(
         document.getElementById("graphdiv"),
@@ -205,19 +289,18 @@
 </html>
-
- +
-

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).

+ + +

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.

Error Bars

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 +/-n 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. σ = sqrt((σ_1^2 + σ_2^2 + ... + σ_n^2)/n))

@@ -237,7 +320,7 @@ </head> <body> <div id="graphdiv" - style="width:800px; height:400px;" + style="width:600px; height:300px;" ></div> <script type="text/javascript"> $ = document.getElementById; @@ -255,8 +338,10 @@ g = new Dygraph( </html> -
- - +

Things to note here:

-

One last demo

+

Internet Explorer Compatibility

+ +

The dygraphs library relies heavily on HTML's <canvas> tag, which +Microsoft Internet Explorer does not support. Fortunately, some clever engineers +created the excanvas +library, which imlements the <canvas> tag in IE using VML.

+ +

You can add IE support to any page using dygraphs by including the following +in your page:

+ +
+<head>
+<!--[if IE]><script src="excanvas.js"></script><![endif]-->
+</head>
+
+ +

This works quite well in practice. Charts are responsive, even under VML +emulation.

+ +

One common gotcha to look out for: make sure you don't have any trailing +commas in parameter lists, e.g.

+ +
new Dygraph(el, data, {
+  showRoller:true,  // <-- note trailing comma
+})
+ +

Most browsers will ignore the trailing comma, but it will break under IE.

+ +

GViz Data

+

The Google + Visualization API 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.

+ +

For a simple demonstration of how to use dygraphs a GViz visualization, see +this page. 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 this + spreadsheet. The URL for the gadget is +http://danvk.org/dygraphs/gadget.xml.

+ +

Here's an example of a published gviz gadget using dygraphs:

+ + + +

Charting Fractions

+

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:

+ + + +

Fortunately, dygraphs handles both of these for you! Here's a chart and the command that generated it:

+ +
Batting Average for Ichiro Suzuki vs. Mariners (2004)
+
+ + +

Command:

+
+new Dygraph(
+  document.getElementById("baseballdiv"), "suzuki-mariners.txt",
+  {
+    fractions: true, errorBars: true,
+    showRoller: true, rollPeriod: 15
+  });
+
+ +

The fractions option indicates that the values in each column should be parsed as fractions (e.g. "1/2" instead of "0.5"). The errorBars option indicates that we'd like to see a confidence interval around each data point. By default, when fractions is set, you get a Wilson confidence interval. If you look carefully at the chart, you can see that the error bars are asymmetric.

+ +

A couple things to notice about this chart:

+ + +

One last demo

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.

-
+
+

Other Options

These are the options that can be passed in through the optional third parameter of the Dygraph constructor. To see demonstrations of many of these options, browse the dygraphs tests directory.

- +
+ + + + + + @@ -426,7 +612,7 @@ perl -ne 'BEGIN{print "Month,Nominal,Real\n"} chomp; ($m,$cpi,$low,$close,$high) - + @@ -434,6 +620,23 @@ perl -ne 'BEGIN{print "Month,Nominal,Real\n"} chomp; ($m,$cpi,$low,$close,$high) + + + + + + + + + + + +
NameSample ValueDescription
includeZerotrue, falseUsually, 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.
rollPeriod 7 Number of days over which to average data. Discussed extensively above.Additional styles to apply to the currently-highlighted points div. For example, { 'font-weigth': 'bold' } will make the labels bold.
highlightCircleSize 3
drawPointsfalseDraw 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. Default: false
pointSize1.0The 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.
pixelsPerXLabel, pixelsPerYLabel 50 Number of pixels to require between each x- and y-label. Larger values @@ -501,8 +704,6 @@ perl -ne 'BEGIN{print "Month,Nominal,Real\n"} chomp; ($m,$cpi,$low,$close,$high)
-

Any options you specify also get passed on to PlotKit's Renderer class. dygraphs will override some of these (e.g. strokeColor), but others may be useful. The padding property is an example of this.

-

Common Gotchas

Here are a few problems that I've frequently run into while using the dygraphs library.

@@ -526,9 +727,29 @@ dygraphs library.

  • Don't set the dateWindow property to a date. It expects milliseconds since epoch, which can be obtained from a JavaScript Date object's valueOf method.
    • + +
  • 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.
    • + +

    Data Policy

    +

    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.

    +

    Created May 9, 2008 by Dan Vanderkam

    +
    + + + + + +