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## Re: uniq function?

 From: John W. Eaton Subject: Re: uniq function? Date: Tue, 3 Nov 1998 17:55:11 -0600 (CST)

```On  3-Nov-1998, Daniel Heiserer <address@hidden> wrote:

| Well intersection bases on create_set as far as I have seen.
| Here a little benchmark between "create_set" and "unique".
| Unique is a factor 70 faster!!!!
|
| octave:3> a=1:1000000;
| octave:4> b=[a,a];
| octave:5> b=sort(b);
| octave:6> tic;c=unique(b);toc
| ans = 11
| octave:7> tic;d=create_set(b);toc
| ans = 721
| octave:8> e=find(c-d)
| e = [](0x0)

The trouble is that create_set and intersection (and union, because it
calls create_set) use loops when they should probably use find or some
other method instead.  The comments in those files say that I wrote
them, but I think that is incorrect.  They were added a long time ago
and I don't remember who contributed them.  I'll see if I can figure
out who did and fix the comments.

Any volunteers for speeding them up?

Thanks,

jwe

```

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