filtering values of one matrix according to another

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Sara on 10 Oct 2012
Hi, I want to filter out rows of one matrix (V) according to values in another (F) and store them in another matrix, V1. F corresponds to some values in the 3rd column of V. The values in F are non-consecutive so a simple loop wouldn't work. Yet filtering using logical indexing (which I normally use) won't work either since F is not a scalar. I'm not a programmer and not a frequent matlab user so it's difficult for me to grasp what's going wrong. I've pasted some of the versions that haven't worked below:
%1 -- didn't work because F is neither a scalar nor the same size of V
F = [4;5;6;9;10;11];
V1 = V((V(:,3) == F ):);
%2 -- this gave a syntax error
start(F(1,1);
end(F(6,1);
V1 = V((V(:,3) >= start <= end ):);
Sounds really stupid but I don't know how to do this?
Sorry!
Thomas on 10 Oct 2012
give an expample of your two inputs and the output you need.. would be easier for us to understand the question..

Andrei Bobrov on 10 Oct 2012
V1 = V(ismember(V(:,3),F),:);

Sara on 10 Oct 2012
Brilliant! Thanks