python-meep team mailing list archive

[Filip Dominec <947797@xxxxxxxxxxxxxxxxxx>]

Public bug reported:

(This may be an error in the MEEP utilities themselves.) Harminv uses
integers instead of floats at some place. When all the constants
(resolution, dimensions and time) are scaled   properly so that the
simulation output looks the same, Harminv does behave differently.

When the simulation resolution is scaled down, one comes to a zero "data
capture time":

   runWithHarminv starting : sources will stop at time = 0 and will
capture data for Harminv analysis during an additional time of 0.

This causes Harminv to fail, mostly returning "On entry to ZGEBAL
parameter number 3 had an illegal value" or "...invalid argument to
ZGEEV". Unfortunately I can not fix the error in the harminv C++ code.

A quick workaround is to get along without SI units and rescale all
constants to use high enough numeric values.

To reproduce the error, see the script attached.

** Affects: python-meep
     Importance: Undecided
         Status: New


** Tags: harminv meep

-- 
You received this bug notification because you are a member of python-
meep, which is the registrant for python-meep.
https://bugs.launchpad.net/bugs/947797

Title:
  With small scale, Harminv has rounding error

Status in Python binding for MEEP (FDTD solver by MIT):
  New

Bug description:
  (This may be an error in the MEEP utilities themselves.) Harminv uses
  integers instead of floats at some place. When all the constants
  (resolution, dimensions and time) are scaled   properly so that the
  simulation output looks the same, Harminv does behave differently.

  When the simulation resolution is scaled down, one comes to a zero
  "data capture time":

     runWithHarminv starting : sources will stop at time = 0 and will
  capture data for Harminv analysis during an additional time of 0.

  This causes Harminv to fail, mostly returning "On entry to ZGEBAL
  parameter number 3 had an illegal value" or "...invalid argument to
  ZGEEV". Unfortunately I can not fix the error in the harminv C++ code.

  A quick workaround is to get along without SI units and rescale all
  constants to use high enough numeric values.

  To reproduce the error, see the script attached.

To manage notifications about this bug go to:
https://bugs.launchpad.net/python-meep/+bug/947797/+subscriptions