[Wannier] default value of kubo_freq_max

[Gibertini Marco]

Dear Wannier90 users and developers,

I realized that the default setting of kubo_freq_max does not guarantee 
that *kubo_freq_max > 0*.
This means that kubo_nfreq can be negative by default, with ensuing 
crashes of mpi when trying to broadcast kubo_freq_list at the beginning 
of postw90 calculations.

This is quite annoying because it affects all post-processing 
calculations (not just Kubo), i.e.
even when one is not interested in properly setting the Kubo frequency 
limits.
For instance I discovered this inconsistency by doing a DOS calculation 
where by default kubo_freq_max was negative and kubo_nfreq=-82:

Fatal error in PMPI_Bcast: Invalid count, error stack:
PMPI_Bcast(2011): MPI_Bcast(buf=0x100, count=-82, MPI_DOUBLE_COMPLEX, 
root=0, MPI_COMM_WORLD) failed
PMPI_Bcast(1903): Negative count, value is -82

I believe that a simple check that kubo_freq_max is positive would be 
sufficient to solve the problem (and use the current fallback otherwise, 
i.e. "the difference between the maximum and the minimum energy 
eigenvalue stored in seedname.eig, plus 0.6667").

Kind regards,
Marco Gibertini

-- 
****
Marco Gibertini
****************************************
Post-doctoral Research Scientist
Theory and Simulation of Materials (THEOS)
École Polytechnique Fédérale de Lausanne

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/wannier/attachments/20140819/97a23ed4/attachment.html>