Copy elements from one matrix to another under a condition

Hi guys I was wondering if there's an efficient way of doing this.

Say I have matrix A = [1 0; 1 0] and matrix B = [0.5 0.4; 0.4 0.3]

I want to transform the entries of A which are 1 to their corresponding entries in B. For instance, my desired result is A' = [0.5 0; 0.4 0]. I know I can use a for loop but in the case in which A has a large dimension this would be very consuming. any shortcuts you know of?

I was thinking of this command A(A==1) = ? or some sort.

(In my application, A would be the adjacency matrix of a graph, B would be the edge weights. Although the A matrix I gave is atypical since the node 1 has a loop connecting to itself)

Thanks!

Answer 1

[Andrei Bobrov]

out = B.*A

[imperial1991]

neat! thanks andrei