Efficient way of finding common elements of two arrays?

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Dear all,
I have two arrays of different size, for example x1=2:1000; and x2=50:1500; I would like to find common elements so my exepcting answer is x3=[50:1000].
Here is the code I'm using right now, but it is too slow.
x1=2:1000;
x2=50:1500;
lx1=length(x1);
lx2=length(x2);
x1 = [x1, zeros(1,length(x2)-length(x1))];
x2 = [x2, zeros(1,length(x1)-length(x2))];
for i=1:length(x2);
for j=1:length(x1);
com(i,j)=x2(i)==x1(j);
end
end
row_com = sum(com);
[~, idx]= find(row_com);
common= x1(idx)
%matchFeatures
How can I do more efficient, preferably without using for loops? Thank you very much for any guidance or advice you could give me.
Regards,
Ivan

Accepted Answer

dpb
dpb on 8 Jan 2015
doc intersect % and friends
  1 Comment
Ivan Shorokhov
Ivan Shorokhov on 8 Jan 2015
Thank you very much for the help, the intersect function took only 0.033s to run, so it is more efficient that my code (0.466 s).

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