[Clp] Possible different treatment for Bounds and Constraints Section

[Emrah Tanriverdi]

  I was trying to solve a problem with CLP, and I encountered a Primal Infeasibility with tolerance of 1.0e-6. After a cumbersome debugging procedure, I found that it is because of a Variable in Bound Section (that it shouldn't cause). So, I changed the place of the Upper Bound of the Variable from Bound Section to Constraint Section, and then CLP was able to solve it to optimality. With same upper bound in Bounds Section, CLP complaint infeasibility, whereas it solved to optimality when it is in Constraint Section.
    It seems, Constraint Section and Bound Section has different rounding or treatment or may be it was because of perturbation we are using. Can someone explain what is going on and what may be the cause?
    Thanks,
    Emrah



      
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://list.coin-or.org/pipermail/clp/attachments/20090519/507c9026/attachment.html>