Matrix-vector boolean comparison

I might be having a brain fart, but if I'm not...

I have a matrix M (mxn) and a vector V (mx1). On each row of M, I want to see how many elements are greater than the element on the corresponding row of V. That is, I want R, where

for i=1:m;
  R(i)=length(find( M(i,:) > V(i)));
end

My question is - can I do this without a loop? Is there a one line operation for this? I know the loop in the example is trivial, but I'm trying to optimize code that takes hours to run and where I run through the loop many many times.

Answer 1

[Sean de Wolski]

Sure:

R = sum(bsxfun(@gt,M,V),2)

Also note, just preallocating R would save you a lot of time for large m.

R = zeros(m,1); 
for ii =...
   R(ii) = ...
end

[Greg]

Awesome. Preallocating was done, smarter things weren't. Thanks!