Flot

About （部分中文翻译）##

Flot is a Javascript plotting library for jQuery.
Read more at the website: http://www.flotcharts.org/

Take a look at the the examples in examples/index.html; they should give a good impression of what Flot can do, and the source code of the examples is probably the fastest way to learn how to use Flot.

Installation

Just include the Javascript file after you've included jQuery.

Generally, all browsers that support the HTML5 canvas tag are supported.

通常来说，所有的浏览器都支持HTML5 canvas标签。

For support for Internet Explorer < 9, you can use Excanvas excanvas, a canvas emulator; this is used in the examples bundled with Flot. You just include the excanvas script like this:

对于IE9以下的版本，你可以使用Excanvas，这是一个canvas的反正器，例子那里有用到。你只需要引入下面的语句即可：

<!--[if lte IE 8]><script language="javascript" type="text/javascript" src="excanvas.min.js"></script><![endif]-->

If it's not working on your development IE 6.0, check that it has support for VML which Excanvas is relying on. It appears that some stripped down versions used for test environments on virtual machines lack the VML support.

You can also try using Flashcanvas, which uses Flash to do the emulation. Although Flash can be a bit slower to load than VML, if you've got a lot of points, the Flash version can be much faster overall. Flot contains some wrapper code for activating Excanvas which Flashcanvas is compatible with.

You need at least jQuery 1.2.6, but try at least 1.3.2 for interactive charts because of performance improvements in event handling.

Basic usage

Create a placeholder div to put the graph in:

创建一个id为placeholder的DIV标签用来作图：

<div id="placeholder"></div>

You need to set the width and height of this div, otherwise the plot library doesn't know how to scale the graph. You can do it inline like this:

你必须为这个Div设置好宽度跟高度，否则plot不知道如何按什么比例去作图，你可以像下面一样采用用行内样式：

<div id="placeholder" style="width:600px;height:300px"></div>

You can also do it with an external stylesheet. Make sure that the placeholder isn't within something with a display:none CSS property - in that case, Flot has trouble measuring label dimensions which results in garbled looks and might have trouble measuring the placeholder dimensions which is fatal (it'll throw an exception).

Then when the div is ready in the DOM, which is usually on document ready, run the plot function:

$.plot($("#placeholder"), data, options);

Here, data is an array of data series and options is an object with settings if you want to customize the plot. Take a look at the examples for some ideas of what to put in or look at the API reference. Here's a quick example that'll draw a line from (0, 0) to (1, 1):

$.plot($("#placeholder"), [ [[0, 0], [1, 1]] ], { yaxis: { max: 1 } });

The plot function immediately draws the chart and then returns a plot object with a couple of methods.

What's with the name?

First: it's pronounced with a short o, like "plot". Not like "flawed".

So "Flot" rhymes with "plot".

And if you look up "flot" in a Danish-to-English dictionary, some of the words that come up are "good-looking", "attractive", "stylish", "smart", "impressive", "extravagant". One of the main goals with Flot is pretty looks.

Notes about the examples