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Topic: Using Intersect Without Removing Repetitions
Replies: 3   Last Post: Aug 24, 2015 7:09 AM

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 Jos Posts: 1,268 Registered: 10/24/08
Re: Using Intersect Without Removing Repetitions
Posted: Jan 10, 2013 8:01 AM

"zcbtf89" wrote in message <kcm7q0\$m1u\$1@newscl01ah.mathworks.com>...
> I would like to do the following:
>
> [C ind] = intersect(A,B);
>
> Where A(100,1), is a vector with a list of consecutive values from 1 to 1000 in a random order (i.e. value 3 is in row 11),
> And B (5,1) is a vector with a shorter list of values all of which occur in A at some location. However there are some repetitions i.e. [1 3 5 5 70] ...
>
> I would like my output vector 'ind' to account for these repetitions in B, such that the index in A repeats itself. i.e. for the above example ind = [ 1 11 25 25 100].
>
> Any help regarding this would be much appreciated,
>
> Thanks!

I think ISMEMBER can do that for you

[tf,ind] = ismember(B,A)

~ Jos

Date Subject Author
1/10/13 Tanya
1/10/13 Jos
1/10/13 Tanya
8/24/15 Jerome