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Dear All,<br>
<br>
I'm using scip 3.1.1 with soplex 2.0.1. (on 1 thread) through C++.
I'm deailing with a branch-and-price procedure for a MILP. The
problem contains continuous and binary variables where the binary
variables have lazy upper bound (the minimization problem has a set
partition structure so an LP solution should respect these bounds).<br>
<br>
I have made a pricer and a branching rule, of course, and I'm
expecting SCIP to call my function scip_execlp. And SCIP does it
usually, but sometimes calls the function scip_execps, and I can't
find its reason.<br>
<br>
Okay, it's clear from the documentation that SCIP calls scip_execps
if 'an integral solution violates one or more constraints and this
infeasibility could not be resolved...', but what does it mean?
Hasn't SCIP solved the LP in the focused node? I have made an event
handler to check the solving steps and I've got the following
output:<br>
<i>...</i><i><br>
</i><i>[nodefocused] node 11 has been focused and is now the focus
node</i><i><br>
</i><i>[firstlpsolved] initial LP of node 11 was solved</i><i><br>
</i><i>[lpsolved] LP of node 11 was completely solved with cut &
price</i><i><br>
</i><i>[nodebranched] the focus node 11 has been solved by branching</i><i><br>
</i><i>...</i><br>
so it means for me that the LP has been solved. But the branching
procedure used the function scip_execps instead of scip_execlp, and
I still don't see the reason. Can you explain it me?<br>
<br>
On the other hand, I wanted to check if a solution violates some
constraints (something like SCIPchecksol). I can get the variables
of a constraint, but I haven't found any procedure to get the
coefficient of a variable in a given constraint. Is there an easy
way to get it?<br>
<br>
Best Regards,<br>
Markó Horváth
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