[SciPy-user] installation problem w/ scipy 0.2: flbas.so has undefined symbol srotmg_

Pearu Peterson pearu at cens.ioc.ee
Mon Jun 3 14:09:20 CDT 2002

On Mon, 3 Jun 2002, David Marimont wrote:

> I built and installed the complete lapack library (AFAIK), rebuilt
> atlas and scipy, and I'm still getting errors.  Here's what happens
> where I try to import scipy:
> [marimont at serenity scipy_distutils]$ python
> Python 2.2 (#1, Dec 24 2001, 15:43:58)
> [GCC 2.96 20000731 (Red Hat Linux 7.1 2.96-98)] on linux2
> Type "help", "copyright", "credits" or "license" for more information.
>  >>> import scipy
> exceptions.ImportError: /usr/local/lib/python2.2/site-packages/scipy/linalg/flapack.so: undefined 
> symbol: sgesdd_

How did you rebuilt scipy? It is possible that this flapack.so is from the
previous built. I suggest `rm -rf build' and `python setup.py'.

You can also check if a library contains a specific symbol using nm
command. E.g.

  nm /usr/local/lib/liblapack.a | grep sgesdd

should show something like

00000000 T sgesdd_

> I noticed in the install file with the scipy distribution that I
> should include all sorts of version info when I ask for help -- it's
> below.  


> The only strange thing I noticed is that when I build scipy,
> it only listed the atlas libraries as found, not the blas or lapack
> ones, but when I ask for system_info, the blas and lapack ones are
> listed.  Does that mean that scipy isn't using the atlas versions?

This is OK. When excecuting `python system_info.py', it will display all
resources. But when building scipy, it finds atlas and therefore it does
not need to check for blas or lapack libraries. If scipy build would not
find atlas, then it would also look for blas/atlas libraries.

> [root at serenity site-packages]# python scipy_distutils/system_info.py
> atlas_info:
>    FOUND:
>      libraries = ['lapack', 'f77blas', 'cblas', 'atlas']
>      library_dirs = ['/usr/local/lib']

To make sure, when you rebuild atlas, did you installed it to
/usr/local/lib or /usr/local/lib/atlas?

If none of the hints above are helpful, could you explain exactly how did
you built/installed lapack,atlas, and scipy. Outputs of command executions
can be useful.


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