Re: [gentoo-science] [sage-on-gentoo] cannot build Sage because of Sympy-0.7.1

Quoting v_2e@×××.net:

> On Thu, 16 Aug 2012 21:28:07 +1200
> Francois Bissey <fbissey@××××××××××××.nz> wrote:
>
>> you have numpy-1.6.xx installed don't you? I am adding that to the
>> list of pains related to the fact we are stuck with numpy-1.5
>   No, I don't. In fact, numpy-1.6 has been masked in
> my /etc/portage/package.mask file for a while.
>   Currently I've got dev-python/numpy-1.5.1 installed.
>
OK wrong assumption from me by looking at the code. You have probably enabled
the gmp useflag in mpmath and now you have gmpy on your system. I am 
now fairly
sure that gmpy is the cause of the problem.
Like sage gmpy can be autoloaded by mpmath but if both are present at the same
time  you get the confusion that you have seen. As a quick check you can try:
MPMATH_NOGMPY=1 emerge -1v sympy
that should work. Adding that variable to sage-env may help with potential
problems importing mpmath or sympy in sage but really mpmath has to change
their default behavior.

Francois