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Re: speed of octave interpreter
From: |
David Bateman |
Subject: |
Re: speed of octave interpreter |
Date: |
Thu, 29 Sep 2005 09:56:01 +0200 |
User-agent: |
Mozilla Thunderbird 0.8 (X11/20040923) |
Brendan Drew wrote:
The STL uses a hybrid of quicksort and heapsort (introspectsort I
believe it's called) which works by using quicksort until the stack
depth reaches some predetermined threshold. At this point, it switches
to heapsort to solve that subproblem. Results are what you'd expect
for a quicksort with guaranteed O(n lg n) run time. SGI's numbers
placed it roughly neck-and-neck with qsort on non-pathological inputs
(i.e. roughly twice as fast as heapsort), but significantly better
than heapsort on pathological inputs. Maybe this is worth investigating?
~B
Brendan,
I'm sorry this is a case where I'll have to say "show me the code"... I
spent a large amount of time on sort and got about a factor of 5 speed
up. The most I'd expected you could get as an improve now is 70% (the
difference in the worst case with matlab) and so I personally don't want
to spend the effort improving it further. Of course if you come up with
something better, I'd be happy to see my code thrown out in favour of
yours...
Cheers
David
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- Re: speed of octave interpreter, (continued)
- Re: speed of octave interpreter, John W. Eaton, 2005/09/26
- Re: speed of octave interpreter, Mike Miller, 2005/09/26
- Re: speed of octave interpreter, Robert A. Macy, 2005/09/26
- Re: speed of octave interpreter, Mike Miller, 2005/09/26
- Message not available
- Message not available
- Re: speed of octave interpreter, David Bateman, 2005/09/27
- Re: speed of octave interpreter, Paul Thomas, 2005/09/27
- Re: speed of octave interpreter, changed to vecorization, Henry F. Mollet, 2005/09/27
- Message not available
- Re: speed of octave interpreter, Mike Miller, 2005/09/27
- Re: speed of octave interpreter, David Bateman, 2005/09/28
- Re: speed of octave interpreter, Brendan Drew, 2005/09/28
- Re: speed of octave interpreter,
David Bateman <=
- Re: speed of octave interpreter, Brian Blais, 2005/09/26
- Re: speed of octave interpreter, Francesco Potorti`, 2005/09/26
- Re: speed of octave interpreter, John W. Eaton, 2005/09/26
- Re: speed of octave interpreter, Javier Arantegui, 2005/09/27
- Re: speed of octave interpreter, Mike Miller, 2005/09/27
- Re: speed of octave interpreter, Javier Arantegui, 2005/09/27
- Re: speed of octave interpreter, Andy Adler, 2005/09/27
- Funding - Specifically identifying allocations, Robert A. Macy, 2005/09/27
- Funding - Specifically identifying allocations, John W. Eaton, 2005/09/27
- Re: Funding - Specifically identifying allocations, Javier Arantegui Jimenez, 2005/09/28