How do I replace certain values of a vector A that are greater than certain values of a vector B for the values this vector?

My problem is the following: I have a matrix A(x,y) that some of it values are greater than a vector B(x) that sets a limit of amplitude. I want to replace the values of A that are greater than the values of B for the respective values of B. I tried this code but without succsess:

for ii = 1:size(A,1)

    A(A(ii,:) > B(ii)) = B(ii);

end

Any clarification will help a lot! Thanks in advance.

Answer 1

[Adam Danz]

Here's a solution with fake data that match the dimensions in your question (an earlier answer by me, now deleted, used a vector instead of a matrix for A).

% fake data
A = [ 9 2 3; 4 5 6; 1 1 8];
B = [2;3;9]; 

%replicate B to match A
Br = repmat(B, 1, size(A,2));

%Replace values in A that exceed vals in B
A(A>Br) = Br(A>Br);

[Adam Danz]

Note that this solution (and Stephen's) takes care of the whole matrix at once. It looks like you're doing this in a loop which will require adaptation if you decide to keep the loop. Stephen's bsxfun solution is higher level and is unnoticeably slower (microseconds) than mine. If you're looking for a 1-liner, use Stephen's solution.

Answer 2

[Stephen23]

>> A = [9,2,3;4,5,6;1,1,8];
>> B = [2;3;9];

Method ONE: for MATLAB versions R2016b+ with implicit scalar expansion, all you need is:

>> min(A,B)
ans =
   2   2   2
   3   3   3
   1   1   8

For older versions try the two following methods.

Method TWO: repmat with min:

>> min(A,repmat(B,1,3))
ans =
   2   2   2
   3   3   3
   1   1   8

Method THREE: Use min with bsxfun:

>> bsxfun(@min,A,B)
ans =
   2   2   2
   3   3   3
   1   1   8

Answer 3

[Matheus Henrique Fessel]

Thank you so much, gentlemen! You were very helpful and both suggestions work perfectly!