[Coin-lpsolver] Presolve removed variable's values?

[Sathi]

Hi,

I have an LP problem in which presolve removes a lot of variables. I have
attached the presolve statistics for a model I have.

While solving the presolved model, I would like to use some relationships
between the original variables in guiding the pivoting heuristic.  So I am
interested in two issues:

1. Which variables are removed? How do the variables in the presolved
model map to the original variables?

2. What values are the removed variables fixed at, if any?  Or, are the
values of some of the removed variables are only fixed during postsolving
process?

I am at present looking at presolve literature and also the COIN presolve
codes to figure out these issues. Any help would be useful to me.

Thanks,
Sathi

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