How to replace elements in a vector?

I have a vector and want to replace all 2's that appear in the vector with a 3 and all 3's with a 2. I can't find a way to do this in a script without a 2 becoming a 3 then automatically becoming a 2 again.

Answer 1

[Thorsten]

First determine the indices of the 2's and 3's, then replace them:

 idx2 = v == 2;
 idx3 = v == 3;
 v(idx2) = 3;
 v(idx3) = 2;