How to trim data in a matrix?

I have a matrix 800x800, from X(0:130) and X(589:end) is garbage. How do i remove the data so that i can surface plot it?

If there is a link on how to manipulate data in MATLAB i'd appreciate it, it seems i spend most of my time goofing around with this type of stuff. Any help is greatly appreciated.

[Rik]

You mean like this?

X_smaller=X(131:588,131:588);

Answer 1

[jonas]

X(0) is not a valid index. Try this:

X(:,[1:130,589:end])=[];

This removes the columns from 1 to 130 and 589 onward, so that you end up with a matrix of size ~800x450,

You could have a read here ( link )