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<div class="moz-cite-prefix">A preprocessing error was fixed
recently which might have something to do with the problem. Try
the latest Cbc/stable. Also try switching off preprocessing. If
that gives a feasible solution then there is obviously a bug - I
can look at problem.<br>
<br>
John Forrest<br>
<br>
<br>
<br>
On 10/11/15 12:28, Mona Rahn wrote:<br>
</div>
<blockquote
cite="mid:CAJW3XALXZW9X5A6eKe6HKP4iRDMih3d+=RYoQN_4Kv6oLKFZyQ@mail.gmail.com"
type="cite">
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<div><span style="font-size:12.8px">Hello,</span><br>
</div>
<div><span style="font-size:12.8px"><br>
</span></div>
<div><span style="font-size:12.8px">I have an LP where I get the
message </span></div>
<div><span style="font-size:12.8px"><br>
</span></div>
<div><span style="font-size:12.8px">"Cut generators found to be
infeasible!</span></div>
<div><span style="font-size:12.8px">Preprocessing says
infeasible or unbounded"</span></div>
<div><span style="font-size:12.8px"><br>
</span></div>
<div><span style="font-size:12.8px">The problem can't be
unbounded (it's a minimization problem and the objective is
of the form a*x, a>0, x>=0).</span></div>
<div><span style="font-size:12.8px"><br>
</span></div>
<div><span style="font-size:12.8px">So I tried to analyze the
infeasibility via a (kind of) Lagrangian relaxation (for
every constraint, I added two variables in [0,inf), one with
positive and one with negative coefficient, that appear also
in the objective function with a positive coefficient; by
making them large enough, the constraint is feasible). So
unless I made an error, the relaxed problem cannot be
infeasible. But upon solving this I get the same message
again.</span></div>
<div><span style="font-size:12.8px"><br>
</span></div>
<div><span style="font-size:12.8px">Can somebody please help?</span></div>
<div><span style="font-size:12.8px"><br>
</span></div>
<div><span style="font-size:12.8px">Thank you in advance!</span></div>
</div>
<br>
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