Re: [eigen] some problems with building with AltiVec enabled

[jacob@xxxxxxxxxxxxxxx]

Quoting Gael Guennebaud <gael.guennebaud@xxxxxxxxx>:

> On Fri, Aug 22, 2008 at 4:18 PM,  <jacob@xxxxxxxxxxxxxxx> wrote:
> > I also have numerical stability issues. This is getting annoying because
> > determining if a test passes or not often requires to run it several times
> > (each time with 10 repeats) to see if failure occurs everytime. This is
> > really unfortunate as it could make us ignore a real error that would be
> > only occasionally triggerred.
>
> exactly. So I have a suggestion (maybe wrong): what about generating
> floating point random matrices with a limited number of decimals ?
> this way the loss of precision should be significantly reduced and we
> should be able to reduce the tolerance thresholds to more decent
> values. What do you think ? (we would do that only in the unit tests)

Sounds like an excellent idea. One clarification though (I know that  
you know!) here by decimals you mean binary decimals. Something like  
some_random_integer * 2^-8.

Cheers,
Benoit


----------------------------------------------------------------
This message was sent using IMP, the Internet Messaging Program.