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[Filip Dominec <947797@xxxxxxxxxxxxxxxxxx>]

** Attachment added: "A modified example script reproducing the error"
   https://bugs.launchpad.net/bugs/947797/+attachment/2821169/+files/harmin.meep.py

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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.

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