Getting color of a data series from a flot chart
After seeing the cool new "reputation" tab on the stackoverflow user page, I was inspired to play with the Flot charting library a little. I have a line chart that has several hundred series. Only a couple of these series will be visible at any given time. My data series are grouped into several "categories" and I assign the numeric color index based on that category. I'd like to be able to see what actual color was assigned by Flot to a particular color index value, for the ultimate purpose of creating a custom legend that relates the color to my "category" of data. How can I get these color values?
I see that I can provide my own array for colors, but I am reluctant to do this, because I am not sure how many categories I will have until I load the data. I suppose I could just create an array that's just way too big, but that seems wasteful if it's possible to ask Flot what color each series is.
Answer
There's an example at the bottom of http://flot.googlecode.com/svn/trunk/API.txt that does just that. Something like:
var plot = $.plot(placeholder, data, options)
var series = plot.getData();
for (var i = 0; i < series.length; ++i)
alert(series[i].color);