Question

I have a matrix ‘x’ and a row vector ‘v’; the number of elements in the row vector is the same as the number of columns in the matrix. Is there any predefined function for doing the following operation?

for c = 1 : columns(x)
    for r = 1 : rows(x)
        x(r, c) -= v(c);
    end
end

Answer 1

bsxfun(@minus,x,v)

Here’s an octave demonstration:

octave>  x = [1 2 3;2 3 4]
x =

   1   2   3
   2   3   4

octave> v = [2 0 1]
v =

   2   0   1

octave> 
octave> z=bsxfun(@minus,x,v)
z =

  -1   2   2
   0   3   3