Find and changing element in matrix (double).

I have a 10x10 matrix (double). I would like to check on a specific column (example column 1) for an element which value is equal to 2 (example) and then change the corresponding element in the same row but different column (example column 2) to 0. How can i do this?

Answer 1

[Birdman]

A(A(:,1)==2,2)=0

or

 A(ismember(A(:,1),2),2)=0