Re: [gentoo-science] sage on gentoo -- only use system atlas

[François Bissey]

On 2013-08-22 00:19, Burcin Erocal wrote:
> Hi,
>
> On Wed, 21 Aug 2013 20:02:02 +0800
> P Purkayastha <ppurka@×××××.com> wrote:
>
>>   I need to have a personal installation of Sage to do development
>> work. However, I also want to reduce my upgrade times by installing a
>> system atlas.
>>
>>   To do so, I added the science overlay and emerged
>> sci-libs/atlas[lapack,fortran,threads]. Thereafter, I added the
>> environment variable
>>
>> SAGE_ATLAS_LIB=/usr/lib
>>
>> and proceeded to compile sage in my home directory. Atlas fails with
>> the error that it can not find liblapack. The exact error message is
>> given below:
>>
>> Cannot find liblapack.* in /usr/lib
>> Unable to find one of liblapack, libcblas, libatlas or libf77blas
>> in the directory None
>> Set SAGE_ATLAS_LIB to the directory containing liblapack, libcblas,
>> libatlas and libf77blas (either .a, .so, .dylib extensions) if
>> you wish to use existing ATLAS libraries. For more details, see
>> http://sagemath.org/doc/installation/source.html#environment-variables
>> Unset SAGE_ATLAS_LIB to build ATLAS from source.
>
> if you make Sage believe that the atlas package was installed properly,
> the installation proceeds without trouble. So as a quick workaround,
> just do
>
> touch spkg/installed/atlas-<version_number>
>
> I always do this on my system. It would be good to find out the proper
> solution of course. :)
>
The main problem here is that Gentoo support the installation of 
multiple BLAS/LAPACK at once.
For that reason there is no libraries on the system installed with the 
names:
libcblas.*
libf77blas.*
liblapack.*

My recommendation for you is to create a folder in your home directory 
and
link all the libraries you need with the appropriate name in a lib 
subfolder
and pass the parent directory to SAGE_ATLAS_LIB.

Francois