[Couenne] Assertion failed in BonChooseVariable

[Pietro Belotti]

Giacomo,

this is a recent bug that is a consequence of moving the management of 
integer variables to Couenne (they were previously taken care of by Cbc). 
A recent update to Couenne/src/branch/CouenneObject.cpp takes care of 
that, at least temporarily.

Note: please make sure that you only svn update that file -- other 
recently committed changes seem to break Couenne in some instances. I'm 
looking into this latter issue.

Hope this helps.

Cheers,
Pietro

--
Pietro Belotti
Dept. of Mathematical Sciences
Clemson University
email: pbelott at clemson.edu
phone: 864-656-6765
web:   myweb.clemson.edu/~pbelott

On Fri, 17 Dec 2010, Giacomo Nannicini wrote:

> Hi,
> in Couenne trunk, there is an assertion that sometimes fails when
> branching with CouenneChooseStrong:
>
> couenne: ../../../../../Bonmin/src/Algorithms/Branching/BonChooseVariable.cpp:969:
> virtual void Bonmin::BonChooseVariable::updateInformation(const
> OsiBranchingInformation*, int, OsiHotInfo*): Assertion
> `object->upEstimate()>0.0&&object->downEstimate()>0.0' failed
>
> I couldn't find out why this happens but it may be worth having a
> look: the values object->upEstimate() and object->downEstimate()
> appear in some denominators later on, so, this could cause some
> Infinity/NaN, hence troubles. I'll let you know if I discover the
> source.
>
> Giacomo
>
> _______________________________________________
> Couenne mailing list
> Couenne at list.coin-or.org
> http://list.coin-or.org/mailman/listinfo/couenne
>