Add values to vector

I have the following vectors A and B

A= [20  80  -1  0.1  0.05  0.25  0.13     0.12  0.35  21  70      -1  0.1  0.2     0.7  20  77            -1  0.15  0.15  0.7];
B= [1   1    1   1    1     1     1    0    1     1   1   1  0  0  1   1   1  0  0  1   1   1  0  0  0  0  1  1     1  1];

And I would like to create vector C

C= [20  80  -1  0.1  0.05  0.25  0.13  0  0.12  0.35  21  70  0  0  -1  0.1  0.2  0  0  0.7  20  77  0  0  0  0  -1  0.15  0.15  0.7];

I use

I=find(B==0);

to find the indices of B where there is a 0 and I thought about inserting a zero in A in those indices but I do not know how. I also thought about somehow replacing the 1 in B by values of A but again I do not how to do this.

Is there any way to do this?

Thanks in advance

Answer 1

[Stephen23]

"I also thought about somehow replacing the 1 in B by values of A"

You can use logical indexing. Here is an example that will work if B is either logical or numeric, and does not overwrite the existing variables:

C = double(B);
C(B==1) = A

If B is numeric and you don't mind overwriting its values, then you just need this:

B(B==1) = A

[AM]

Oh I see, thank you!

Answer 2

[Adam]

B( B == 1 ) = A

[AM]

Thank you!