If you can reduce this to a standalone, runnable test case that uses only code 
from Base, it would be helpful to file an issue.

--Tim

On Saturday, January 17, 2015 05:36:36 PM Arch Call wrote:
> Give alg=MergeSort a whirl.  The doc says this is slower than alg=QuickSort
> for numeric arrays, but who knows until you try.
> 
> On Saturday, January 17, 2015 at 4:57:20 PM UTC-5, Petr Krysl wrote:
> > Hi guys,
> > 
> > This one has me scratching my head.
> > 
> > Matlab code:
> > 
> > function  Out  =myunique(A)
> > 
> >     sA=sort(A,2);
> >     [sA,rix]  = sortrows(sA);;
> >     d=sA(1:end-1,:)~=sA(2:end,:);
> >     ad=[true; any(d,2)];
> >     iu =find((ad&[ad(2:end);true])==true);
> >     Out =A(rix(iu),:);
> > 
> > end
> > 
> > was rewritten in Julia. Since some of the functionality is different (or
> > slower) as written, I had to rewrite a bit.  The surprise was that even
> > after the rewrite the Julia code runs in around 24 seconds whereas the
> > Matlab code gets it done in two seconds.  As I went poking around to find
> > what is slow, I found that 95% of the time were spent in the sort() and
> > sortrrows() functions.
> > 
> > Any idea of what could cause this slowness? By the way, @code_warntype
> > gives the code a clean bill... So are those two functions somehow slow by
> > themselves?
> > 
> > The Julia version of this  is posted at
> > https://gist.github.com/PetrKryslUCSD/cde67dfa0f1b0a1f98ac
> > 
> > Thanks,
> > 
> > Petr

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