[CIG-SEISMO] external model file question

[Michael Gineste]

Hi Specfem group,

I have a question regarding the external model file input, dependent on
the parameter MODEL. I can not find much on this in the documentation so
what I understand is from the source code...

I need to supply the external model through a external file, so using a
subroutine is not an option, ruling out parameter option 'external'. For
the remaining options, it seems to me that that only option 'default'
and 'tomo' allows you supply a model not to know the mesh partition in
advance. Is this correctly understood?

The 'default' option, which I have used so far, maps a model
specification to an entire element, whereas I wish to pass a model at
finer resolution, and with 'tomo' it gets interpolated onto the GLL
points. Which is fine, but I wonder how one is supposed to handle the
PML elements with this model format.

Must values given at (x,z) points within the PML elements be ensured
constant and equal to (x,z)-points just adjacent to the PML elements, in
the same manner as when one uses the combination nbmodels,
materials_file and absorbing_cpml_file? Or is it handled within the code?

Thank you for your help.

Best regards,
Michael Gineste