[SCIP] How to create initial solution file for ParaSCIP from NL-file

[Vladimir V. Voloshinov]

Dear SCIP Team members,

we are going to try ParaSCIP with rather hard MINLP (with polynomial
functions) problems, which are generated by another application as NL-files
containing initial values of variables.
To prepare input data for ParaSCIP we convert NL to PIP, CIP and OSIL
formats, but initial values that are in NL, are not "passed" in converted
PIP, CIP and OSIL files.

The content of [scipoptsuite-6.0.0/ug/check/instances/MINLP] folder of SCIP
Opt. Suite distribution gave us "a hint" that ParaSCIP accepts problems in
PIP, CIP, MPS and OSIL formats.
According to the list of input formats
http://scip.zib.de/doc-6.0.0/html/group__FILEREADERS.php we tried to
convert NL-files to PIP, CIP and OSIL.
It has been successfully done by SCIPAMPL running in interactive mode:
e.g. for NL-to-PIP convertion:
========================
>echo "write problem some.cip" | scipampl some.nl -i
written original problem to file <some.pip>
========================
The issue is that our NL-file contains initial values of variables ("#
initial guess" section in NL), but <some.pip|cip|osil> - does not have
appropriate "initial values".

May be all these formats (PIP, CIP, OSIL) do not support initial values at
all?

If so, are there any recommendations how to "extract" initial values to a
file that can be passed to ParaSCIP via [-isol <initial solution file>]
argument of parascip application?

We'll appreciate any advices,
Vladimir Voloshinov.
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