How can I add four neighbor elements (left, right, top and bottom) of each element of a given matrix and make a new matrix of the same sixe from the calulated values?

For example, let A= [ 0 2 1; 1 0 1; 1 0 2]. Then my resulting matrix should be [3 1 3; 1 4 3; 1 3 1].

Answer 1

[Image Analyst]

Use conv2():

A= [ 0 2 1; 1 0 1; 1 0 2]
kernel = [0,1,0;1,0,1;0,1,0]; % Sum above, left, right, and below
B = conv2(A, kernel, 'same')

[Don]

awsome! thanks!!