Re: [Discuss-gnuradio] accuracy problem?

[David P. Reed]

Eric Blossom wrote:

> On Wed, Jun 01, 2005 at 04:12:16PM -0400, David P. Reed wrote:
>  
>
> > I'm trying to install the gnuradio software from CVS on Fedora Core 3 on 
> > an AMD64 (x86_64) laptop (and python 2.3).   Aside from annoying 
> > pathname bugs and quirks with FFTW linking, which I will report 
> > separately, I get the following error when testing gnuradio-core, where 
> > a unittest fails.   Anyone who has a clue why this imprecision might be 
> > happening?  If I change this one test to check for 5 digits after the 
> > decimal point, it works...
> >
> > Also, has anyone gotten gnuradio to run on x86_64?
> >    
>
> Hi David,
>
> Some folks have GNU Radio running on x86_64.  I just took delivery on
> one the other day, but haven't had a chance to spend any time with it.
>
> I think the difference you're seeing is that GCC for the x86_64 uses
> the SSE scalar mode instructions at 32-bits instead of the x87
> instructions with 80-bits of precision.
>
> Eric
>
>
>  
Yeah, but should the test process stop the build process, or should the 
check be for 5 digits rather than 6?

I'm still trying to figure out why I can't build the gsm codec, 
apparently because of linker errors with fftw (multiply defined symbols).