Re: [Numpy-discussion] Unit test error with numpy rc3

[Charles R H. <cha...@gm...>]

On 10/24/06, Mark Hymers <ma...@hy...> wrote:
>
> On Mon, 23, Oct, 2006 at 11:50:27AM +0100, Mark Hymers spoke thus..
> > Hi,
> >
> > I've just done a Mac OS X PPC build of the SVN trunk and am getting this
> > failure too.
> <snip>
> > FAIL: Ticket #112
> </snip>
>
> I've just been looking into this a bit further (though I may be heading
> down the wrong road) and come across this which doesn't exactly look
> right.  Again this is on a PPC Mac OS X 10.4 install:
>
> In [1]: import numpy
>
> In [2]: numpy.__version__
> Out[2]: '1.0.dev3390'
>
> In [3]: print numpy.finfo(numpy.float32).min, numpy.finfo(numpy.float32).max,
> numpy.finfo(numpy.float32).eps
> -3.40282346639e+38 3.40282346639e+38 1.19209289551e-07
>
> In [4]: print numpy.finfo(numpy.float64).min, numpy.finfo(numpy.float64).max,
> numpy.finfo(numpy.float64).eps
> -1.79769313486e+308 1.79769313486e+308 2.22044604925e-16
>
> In [5]: print numpy.finfo(numpy.float128).min, numpy.finfo(numpy.float128).max,
> numpy.finfo(numpy.float128).eps
> Warning: overflow encountered in add
> Warning: invalid value encountered in subtract
> Warning: invalid value encountered in subtract
> Warning: overflow encountered in add
> Warning: invalid value encountered in subtract
> Warning: invalid value encountered in subtract
> 9223372034707292160.0 -9223372034707292160.0 1.38178697010200053743e-76


These aren't right. Are you running on a 64 bit system? Currently float80,
float96, and float128 are all float80 with different alignments, so show up
as float96 on 32 bit machines and float128 on 64 bit machines. This is
probably set by a combination of compiler defaults and machine architecture.
It sounds like something is getting misidentified, but I don't know much
about that.

Anyone got any comments /thoughts on this?  Should I file it as a bug?
> I just tested this on an x86 Linux box (running Debian though that
> should be irrelevant) and numpy.float128 doesn't exist on x86 Linux
> but float96 does gives:


My impression is that it is a bug.


Chuck