# Output of a vector which excludes the entries of the second vector

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Feng Cheng Chang on 1 Dec 2012
Hello,
Problem: Given two distinct integer vectors p and q. I'd like to get a new vector r, that is p excluding the entries of q.
For example,
p = [1 2 3 4 5 6 7 8], q = [2 5 7 9], then r = [1 3 4 6 8].
Hope to have a code in a singer line. Thanks.

Azzi Abdelmalek on 1 Dec 2012
Edited: Azzi Abdelmalek on 1 Dec 2012
p = [1 2 3 4 5 6 7 8],
q = [2 5 7 9],
out=p(~ismember(p,q))
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Azzi Abdelmalek on 1 Dec 2012
Feng Cheng Chang on 1 Dec 2012

Walter Roberson on 1 Dec 2012
r = setdiff(p, q);
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Walter Roberson on 1 Dec 2012
Note that the two answers are slightly different, having to do with the ordering of the outputs if the first vector is not sorted. setdiff() also has a 'stable' option to get the outputs in the original order.
Matt Fig on 1 Dec 2012
Not in 2011b....