How to compare two matrix?

Hi all,

I have 2 different matrix A and B. I am wondering how to write a script to find how many times does a 1 in matrix A line up with 3 in matrix B. As we can see, in this case, there are 6 times where 1 in matrix A line up with 3 in matrix B, and their locations are all in the first column (Bolded 3 in the matrix B).

A =

[1 1 1 1 1 1 1 1 1 1

1 2 2 2 2 2 2 2 2 1

1 2 3 3 3 3 3 3 2 1

1 2 3 4 4 4 4 3 2 1

1 2 3 4 5 5 4 3 2 1

1 2 3 4 5 5 4 3 2 1

1 2 3 4 4 4 4 3 2 1

1 2 3 3 3 3 3 3 2 1

1 2 2 2 2 2 2 2 2 1

1 1 1 1 1 1 1 1 1 1];

B =

[1 1 1 1 1 1 1 1 0 0

2 2 2 2 2 2 2 1 0 0

3 3 3 3 3 3 2 1 0 0

3 4 4 4 4 3 2 1 0 0

3 4 5 5 4 3 2 1 0 0

3 4 5 5 4 3 2 1 0 0

3 4 4 4 4 3 2 1 0 0

3 3 3 3 3 3 2 1 0 0

2 2 2 2 2 2 2 1 0 0

1 1 1 1 1 1 1 1 0 0];

Please help~

Thank you!

Answer 1

[Walter Roberson]

nnz(A == 1 & B == 3)