Draw Rectangle on graph

[The_Wirjy]

Hi,

I make an application at school. This app must show the area under a function by drawing rectangles, trapezium or with the Simpson method.

Is there a way to draw rectangle on the graph like this :


http://imgur.com/mUcowS5

Thank's

(Sorry for my english, I speak french)

[paradoxoff]

Do you want to show the grey bars or the red circle on the chart?

[The_Wirjy]

I want to show the grey bars. Actually, I have the red line (a sinus function) and i want to draw the grey rectangles.

[paradoxoff]

Do you already have the height of the bars that you want to plot, and their start and end values on the x-axis?
Then, I suggest to use a second dataset, eventually plotted to a secondary y-axis.

[The_Wirjy]

A rectangle is defined like this :

start point : (x,0)
width : ((x+delta) - x) delta is the difference between two point on the sinus
height : f(x) : f represent the sinus function

[paradoxoff]

Then just use an XYIntervalSeriesCollection as secondary dataset. You can plot that to the same axis as the first dataset, since the x and y values will be quite similar.