[Numpy-discussion] OS X PPC problem with Numpy 1.3.0b1

Pauli Virtanen pav at iki.fi
Mon Mar 23 18:01:11 EDT 2009


Mon, 23 Mar 2009 19:55:17 +0000, Pauli Virtanen wrote:

> Mon, 23 Mar 2009 13:22:29 -0600, Charles R Harris wrote: [clip]
>> PPC stores long doubles as two doubles. I don't recall exactly how the
>> two are used, but the result is that the numbers aren't in the form you
>> would expect. Long doubles on the PPC have always been iffy, so it is
>> no surprise that machar fails. The failure on SPARC quad precision
>> bothers me more.
> 
> The test fails on SPARC, since we need one term more in the Horner
> series to reach quad precision accuracy. I'll add that for long doubles.

Another reason turned out to be that (1./6) is a double-precision 
constant, whereas the series of course needs an appropriate precision for 
each data type. Fixed in r6715, r6716.

I also skip the long double test if it seems that finfo(longdouble) is 
bogus.

Backport?

-- 
Pauli Virtanen




More information about the NumPy-Discussion mailing list