Re: pb with -ffast-math

[Jaroslav Hajek]

On Thu, Apr 16, 2009 at 9:51 PM, Alain Baeckeroot
<address@hidden> wrote:
>
> Le 15/04/2009 à 19:56, Jaroslav Hajek  écrit :
>>
>> On Tue, Apr 14, 2009 at 9:54 AM, Alain Baeckeroot
>> <address@hidden> wrote:
>> >
>> > i builded octave with additional optimisation flags
> .../...
>>
>> I use -O3 -march=native -funroll-loops and get good results.
> I'll try this.
>
>>
>> > And this is really not important, i doubt we can get another 20%
>> > speed improvement.
>>
>> Depending on your code, you may get even much better improvements by
>> switching to the development sources (it seems you use 3.0.5). An
>> instance is the experience of F. Potorti:
>> http://www.nabble.com/thanks-for-the-indexing-improvements-td22494818.html#a22494818
>>
> Everythnig is vectorised, except one for-loop (iteration over time) which
>  takes 90% of time !
> We are going to write this short part in C in a .oct file.
>

Could you post the relevant piece of code? Maybe there's a vectorized
way you didn't see, or one that only works with development version,
or maybe it will be something worth a new function.

regards

-- 
RNDr. Jaroslav Hajek
computing expert & GNU Octave developer
Aeronautical Research and Test Institute (VZLU)
Prague, Czech Republic
url: www.highegg.matfyz.cz