create a new matrix with combining two matrices with the same size

My aim is to create a new matrix which the same rows in matrix A and matrix B are zero. the same rows in matrix A which are zero, should also be zero in matrix C.

I want to create matrix C from matrix B.

 A= 
 1 2
 0 0
 3 2
 0 0

 B= 
 7 2
 3 6
 4 5
 2 6

 C= 
 7 2
 0 0
 4 5
 0 0

[Azzi Abdelmalek]

The explanation is not clear

[Paul Sponagle]

Is this what you are trying to do?

A=[1,2;0,0,;3,2;0,0]
B=[7,2;3,6;4,5;2,6]
C=B;
C(A==0)=0

Results in:

C =

       7     2
       0     0
       4     5
       0     0

This will work for all elements of A that are zero. If you only want to modify B if both elements in the row of A are zero this won't work.

Rather than guessing your intent I provided the simpler solution.

Answer 1

[Azzi Abdelmalek]

C=B
C(~any(A,2),:)=0

[Maryam Hamrahi]

Thanks a lot Azzi Abdelmalek.

Answer 2

[Paul Sponagle]

I put this in comments, it should have been in the 'Answers' section.

The question was not quite clear, but I think this might also work:

A=[1,2;0,0,;3,2;0,0]
B=[7,2;3,6;4,5;2,6]
C=B;
C(A==0)=0

Results in:

C =
       7     2
       0     0
       4     5
       0     0

This will create C by copying and modifying B for all elements of A that are zero. If you only want to modify B if both elements in the row of A are zero this won't work and you need to see Aziz's answer.

Paul