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Re: Random timing results with 'fsolve'
From: |
Francesco Potortì |
Subject: |
Re: Random timing results with 'fsolve' |
Date: |
Wed, 12 Oct 2011 18:59:59 +0200 |
>
>On Wed, Oct 12, 2011 at 04:21:57PM +0200, Søren Hauberg wrote:
>> ons, 12 10 2011 kl. 14:02 +0000, skrev bpabbott:
>> > It does look strange.
>> >
>> >
>> > Have you looked at the 2nd (function values) and 3rd (termination
>> > status) outputs of fsolved?
>>
>> Hmm, okay... it seems like the algorithm converges to different solution
>> each time. The problem I'm solving is under-determined so it does not
>> surprise me that the solver can converge to different solutions, but I
>> am surprised that this happens when the solver is given the same
>> starting conditions. Does 'fsolve' perform any random steps?
>>
>> Søren
>
>Wild guess: hardware floating point randomness (maybe due to
>differences between processor cores?) which has only "negligible"
>effect on accuracy, but could change the course of optimization in
>under-determined problems...
??? What is hardware floating point randomness? As far as I know,
floating point is deterministic, on a given processor.
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- Random timing results with 'fsolve', Søren Hauberg, 2011/10/12
- Re: Random timing results with 'fsolve', bpabbott, 2011/10/12
- Re: Random timing results with 'fsolve', Søren Hauberg, 2011/10/12
- Re: Random timing results with 'fsolve', bpabbott, 2011/10/12
- Re: Random timing results with 'fsolve', Søren Hauberg, 2011/10/12
- Re: Random timing results with 'fsolve', Olaf Till, 2011/10/12
- Re: Random timing results with 'fsolve', Søren Hauberg, 2011/10/12
- Re: Random timing results with 'fsolve', Olaf Till, 2011/10/12
- Re: Random timing results with 'fsolve', Sergei Steshenko, 2011/10/12
- Re: Random timing results with 'fsolve',
Francesco Potortì <=
Re: Random timing results with 'fsolve', Martin Helm, 2011/10/12