Replacing values in a matrix based on values in another matrix

If I have a matrix with "1"s and "0"s (A) and other matrixes of the same size with other values (B,C,D, etc), is it possible to find the locations of the "1"s in A in B,C,D,etc and replace these values with a constant number while the other values in B,C,D, etc are uneffected?

Thanks in advanced!

Answer 1

[Cris LaPierre]

Use logical indexing (see Ch 11 of MATLAB Onramp)

A = [0 1 1 0]

A = 1×4

0 1 1 0

B = rand(size(A))

B = 1×4

0.1915 0.9248 0.8352 0.2674

B(A==1) = 99

B = 1×4

0.1915 99.0000 99.0000 0.2674

[Filip Hansson]

Thank you!