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<div class="moz-cite-prefix">Yves,<br>
<br>
Error not where I thought it was. Small changes i.e. order or
compiler or anything made a subtle difference and a constraint was
generated<br>
<br>
x995 + x1018 + x1700 >= 1.0000001001<br>
<br>
and the optimal solution had x995==0,x1018==1 and x1700==0 - but
it was within tolerances (just)<br>
<br>
One of the cut generators then thought 0.0000001001 is greater
than primal tolerance of 1.0e-7 and created a bad cut.<br>
<br>
I have modified code to be a bit more relaxed.<br>
<br>
John Forrest<br>
<br>
On 18/12/13 10:11, Yves Touchard wrote:<br>
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Attached is a archive file (test.gz) containing an lp constraint
file (test.lp -> <i>tar xzf test.gz</i>)<br>
<br>
Executing cbc (#2.8.0) on the test.lp file (<i>cbc test.lp</i>)
provides the following result<br>
<i>Result - Problem proven infeasible</i><i><br>
</i><i>No feasible solution found<br>
<br>
</i>If the two first constraints of the LP file (lines 1258/1259)
are swapped, the same command provides a different result:<br>
<i>Result - Optimal solution found</i><br>
<br>
So, what's wrong with this constraints fle? Is there any specific
order to declare constraints?<br>
Or is this a bug? And, if so, is there any workaround?<br>
<br>
Thanks in advance for any help.<br>
<br>
Regards,<br>
<br>
Yves<br>
<br>
<br>
<br>
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