[petsc-users] slepc4py: How to create a matrix in serial then find its eigenvalues in parallel?

[Alex Eftimiades]

I have a routine that creates a matrix in parallel by spawning 
subprocesse. This is to say it is run from a serial python interpreter, 
but spawns subprocesses so that it works in parallel. The result is a 
scipy csr_matrix.

What would be the best way use slepsc4py to solve for eigenvalues and 
eigenvectors in parallel? I tried a rather awkward method (described 
below), but I suspect there is a better way to go about doing this.

I have currently tried saving the csr data to a file, reading it with a 
new python interpreter spawned with mpiexec, and writing the resulting 
eigenvalues and eigenvectors to a file. However, something is going 
wrong as I read in the file from the python interpreter spawned with 
mpiexec.

Thanks,
Alex Eftimiades