How can I change all the elements in a matrix with value1 to a new value2?

I have a 78X78 binary matrix. How can I change all the 0s to -1s?

Answer 1

[Torsten K]

How about this?

m = randi([0,1],78) % 78x78 matrix with random integers in the interval 0..1
m(m==0)=-1 % Substitute all 0's b -1's

Best regards

Torsten

Answer 2

[Ameer Hamza]

Another approach

M; % 78x78 matrix
M_new = 2*M-1;

This will be faster as compared to the indexing approach.