Question

I have to write a Matlab script that does this:

The input is 2 matrices, A(m x n) and D(m x 1). The output is a matrix, C (m x n). C is calculated like this:

function c = scanrow(a,d)
[rows columns] = size(d);
for i=1:columns
a(i,:) = a(i,:).*d(i);   
end
c = a;
end

The requirement is not using recursion. I have no idea to solve this problem. Glad that you can help.
Thank you.

Answer 1

If the problem is “multiply every element in each row of A with the corresponding element on the corresponding row of D” then I would suggest the following:

dd = repmat(d, 1, size(a, 2))
c = a.*dd

Example:

>> a = [1 2; 3 4; 5 6];
>> d = [1 2 3]';
>> dd = dd = repmat(d, 1, size(a, 2))
dd = 
     1   1
     2   2
     3   3
>> a.*dd
ans =
     1   2
     6   8
     15  18