[Numpy-discussion] eig hangs

[Robert Hetland]

On Jun 12, 2006, at 3:17 PM, Travis Oliphant wrote:

> Robert Hetland wrote:
>
>> I set up a linux machine without BLAS, LAPACK, ATLAS, hoping that
>> lapack_lite would take over.  For the moment, I am not concerned
>> about speed -- I just want something that will work with small
>> matricies.  I installed numpy, and it passes all of the tests OK, but
>> it hangs when doing eig:
>>
>> u, v = linalg.eig(rand(10,10))
>> # ....lots of nothing....
>>
>> Do you *need* the linear algebra libraries for eig? BTW,  inverse
>> seems to work fine.
>>
>> -Rob
>>
>  From ticket #5
>
>> Greg Landrum pointed out that it may be a gcc 4.0 related
>> problem and proposed a workaround -- to add the option '-ffloat- 
>> store' to CFLAGS. Works for me !
>>
> Are you using gcc 4.0?

Well, gcc 4.1, I had forgotten to check that.  The install is on a  
relatively new version of Fedora, FC5.  (all the older redhats I have  
use gcc3..).

$ uname -a
Linux ---.----.--- 2.6.15-1.2054_FC5smp #1 SMP Tue Mar 14 16:05:46  
EST 2006 i686 i686 i386 GNU/Linux

$ gcc --version
gcc (GCC) 4.1.0 20060304 (Red Hat 4.1.0-3)

That seems like the most likely cause of the bug.  I will try with - 
ffloat-store, and with gcc 3.2.3, and let you know if I have the same  
problems.

-Rob.


-----
Rob Hetland, Assistant Professor
Dept of Oceanography, Texas A&M University
p: 979-458-0096, f: 979-845-6331
e: hetland at tamu.edu, w: http://pong.tamu.edu