Numerical integration of double integrals in MAtlab

Hi,

I am trying to integrate an array of numbers in polar co-ordinates. I do not have a defined function for this array of numbers. How can I integrate the array of numbers numerically in matlab? Theta goes from 0 to 2*pi and R goes from 0 to 10.

Thank you, HT

Answer 1

[Matt Fig]

Look at the TRAPZ function.

[Walter Roberson]

That sounded okay at first, under the assumption that the polar was converted to cartesian, but then I realized that in polar plots it is common for the same X cartesian coordinate to have multiple Y, which is a situation that trapz is not designed to handle.

[Andrew Newell]

It depends on what the problem is. If the problem is to integrate inside a curve on a polar plot, you're right. But I think the problem is really just to integrate a function like sin(x) given a set of values [x sin(x)].

[Walter Roberson]

Andrew, the OP stated that theta goes from 0 to 2*pi; as the range is greater than Pi, there must be overlapping X areas.