# [SciPy-User] Calling LAPACK function dbdsqr()?

Philip Semanchuk philip@semanchuk....
Fri Dec 14 14:15:44 CST 2012

On Dec 14, 2012, at 2:38 PM, Pauli Virtanen wrote:

> 14.12.2012 21:24, Philip Semanchuk kirjoitti:
> [clip]
>> The not-so-excellent news is that on Windows I installed scipy 0.11.0
>> (the same version that's on my Mac) and it does *not* seem to provide
>> a reference to dbdsqr(). I also looked for _dbdsqr, dbdsqr_, _dbdsqr_,
>> etc. and it's just not there. I can get a reference to e.g. zgelss --
>>
>>>>> hasattr(scipy.linalg.lapack.flapack, 'zgelss')
>> True
>>
>> But not dbdsqr. I guess this is an artifact of the LAPACK library
>> against which scipy was compiled?
>
> No, the result from hasattr only means that the routine is not wrapped
> via f2py. The Scipy LAPACK wrappers always wrap the exact same set of
> routines.
>
> However, if a routine is not wrapped, the compiler might not include it
> in the built dll file. This probably is platform dependent.

Oh, I see.

When I use `dumpbin.exe /SYMBOLS flapack.pyd`, I see dbdsqr referenced, but I can't access it under any name. ISTR that some other LAPACK function in scipy uses dbdsqr(), so it should be in there but perhaps the symbol is not exported. I can't find it in any of the other .pyd files in site-packages\scipy\linalg.

Cheers
Philip