Hi Daniel,<br>This is something we do see in our customer models, they can be very "close" to being infeasible. Which due to tolerances and finite precision can create different results from optimizer to optimizer. I think you should get the farkas ray ( i.e certificate of infeasibility from farkas lemma ) provided by Clp (which I assume you can get), check the quality (i.e dual infeasibility and objective of the ray). If it seems ok, then its not some numerical issue in Clp and your model can be declared infeasible within tolerances (which might be something to look into to improve the model stability ).<br>
Regards<br>Bo<br><br><div class="gmail_quote">On Tue, Jul 28, 2009 at 11:59 AM, Daniel Bienstock <span dir="ltr"><<a href="mailto:dano@columbia.edu">dano@columbia.edu</a>></span> wrote:<br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
Hello,<br> I have a tough LP that the callable version of Clp declares infeasible; however the command-line version eventually (slowly) solves it but complaining a bit at the end about remaining infeasibilities. Commercial solvers do solve this problem. Question: how can I get the callable version to also solve the problem to optimality. Thanks.<br clear="all">
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<br>-- <br><a href="http://www.columbia.edu/%7Edano" target="_blank">www.columbia.edu/~dano</a><br>
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