MATLAB: Compute average of each value in a matrix without using for

filterfor loopMATLABmatrix manipulation

Hi all,

I was wondering is it possible to alter each value of a matrix based on the average value of its neighbors, wihtout using for loops?

Thanks in advance.

you can use conv2 or imfilter, for example

x = magic(3)
y = conv2(ones(3)/9,x)

I would recommend using diag function.

The following is an example:

A = [1 2 3 4 5;
  6 7 8 9 10];
A = A';
output = diag(A(:));

>> output

output =

1 0 0 0 0 0 0 0 0 0

0 2 0 0 0 0 0 0 0 0

0 0 3 0 0 0 0 0 0 0

0 0 0 4 0 0 0 0 0 0

0 0 0 0 5 0 0 0 0 0

0 0 0 0 0 6 0 0 0 0

0 0 0 0 0 0 7 0 0 0

0 0 0 0 0 0 0 8 0 0

0 0 0 0 0 0 0 0 9 0

0 0 0 0 0 0 0 0 0 10

For any one of them,

sum(T, 3)