[SCIP] SCIPgetVarRedcost

[Peter Notebaert]

I have a small model that contains one integer variable and it contains one
quadratic constraint along with other real variables and linear constraints.

When solved via the scip command and asking to display the dual solution it
says that this information is not available when presolve is active. When
presolve is disabled (set presolving emphasis off) it says that dual
information is only available for pure LPs.

However I am now interested in the variable reduced costs. I don't see a
way to display this via the scip command. Is that correct?

Anyway in fact the model is build in code and I use SCIPgetVarRedcost to
get the reduced costs.
I see that this information is returned even with presolve on and with the
integer variable.
I also note that I get totally different values when presolve is on or off
And I even get non-zero values for basic variables which is also quite
strange I think.

So my question. Is this call possible if there are integer variables /
quadratic constraints and is it possible when presolve is active and if
not, why do I get values? Oh and is there a way to show these values via
the scip command?

Thanks,

Peter
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