Understood. I think you will find that a 2000x2000 2D problem (assuming you
have enough RAM) will not take anything like 7.5 h.
> On Jul 24, 2018, at 3:49 PM, Carsten Langrock wrote:
>
> I tried a few solvers for this 1D diffusion problem and it does indeed appear
> that pySparse is faster
Thanks for the links. I had come across the first one, but I haven’t found any
major speedup using the —inline option on this 1D problem. Initially I thought
that remeshing would be fairly simple, not unlike what our C++ code does. It
wouldn’t speed things up necessarily since our code uses a
I tried a few solvers for this 1D diffusion problem and it does indeed appear
that pySparse is faster than the rest. Sadly, faster doesn’t equate to fast …
about 4 seconds for a 2000 grid, 440 time steps nonlinear diffusion process
using a single sweep. For the second part, which opens the left
Hi Carsten,
Have you looked at:
https://www.ctcms.nist.gov/fipy/documentation/EFFICIENCY.html
http://nbviewer.jupyter.org/github/wd15/fipy-efficiency/blob/master/notebooks/FiPy-IPython.ipynb
https://www.mail-archive.com/fipy@nist.gov/msg03180.html thread
I struggled to install weave and get
Thanks for pointing out the performance order of the solvers. I’ll try to get
pySparse to work to compare it other solvers. It’s also good to know that I
shouldn’t give up on 2D just yet;-)
Regards,
Carsten
_Dipl.-Phys. Carsten Langrock, Ph.D.
Senior
Dario,
Thanks. I was able to install the PyAmg module and use it by adding —pyamg on
the command line. The DefaultSolver on my system appears to be PyTrilinos.
Sadly, with the —pyamg flag, it took significantly longer for the script to run
… and I haven’t yet been able to get pySparse to
FiPy still does not support remeshing.
As Dario said, choice of solver can make a big difference. I've not used PyAMG
much, but PySparse is dramatically faster than SciPy. PyTrilinos is slower than
PySparse, but enables you to solve in parallel.
I've also found that 2D problems solve much
Hi Carsten,
I'll start by saying I'm not a fipy expert, but have been playing around it
for a few months as part of my PhD project.
Regarding your second question.
Performance can be improved by switching from the default (SciPy) solver to
one of the others. I use the PyAmg solver that can
Hi,
Thanks for the help with getting FiPy running under Linux! I am trying to
re-create a 1D nonlinear diffusion problem for which we have C++ code that uses
the implicit Thomas algorithm based on
J. Weickert, B. Romerny, M. Viergever, "Efficient and Reliable Schemes
for Nonlinear Diffusion
