[TriZPUG] undefined symbol after numpy install

Chris Calloway cbc at unc.edu
Wed Jan 26 20:53:21 CET 2011

On 1/26/2011 12:28 PM, Joseph Mack NA3T wrote:
> I've installed numpy on several machines, sometimes it works and
> sometimes it doesn't.

It's about the way lapack is built on the machines where it fails. It 
sounds like you need a shared (not static) lapack built with -fPIC.

On the machines where it fails, see if your *nix distribution has an 
update for lapack. Make sure there are no stray .a lapack libs left 
around after the update.

You may end up having to build lapack yourself if updates don't work.

You can also use alternate linear algebra libraries to lapack, like blas 
or atlas or mkl, with numpy.

Your linear algebra libraries will need to have been built with the same 
C and Fortran compilers as numpy. See:


Finally, you can also install numpy with no linear algebra libraries. 
Numpy will just run a lot slower for some thing. But it will work. You 
can do this with:

BLAS=None LAPACK=None ATLAS=None python setup.py build

If fiddling with configuration isn't how you like to spend time, you 
might consider a pre-built numpy environment like EPD:


or Sage:


or PythonXY



Chris Calloway http://nccoos.org/Members/cbc
office: 3313 Venable Hall   phone: (919) 599-3530
mail: Campus Box #3300, UNC-CH, Chapel Hill, NC 27599

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