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<div class="moz-cite-prefix">James,<br>
<br>
I have checked in changes in trunk. As there is a small overhead
cleaning up SOS variables, the changes are on an option. See
cleanBounds in CbcModel.hpp for more information.<br>
<br>
Preprocessing works for both examples. Keep me informed on
problems.<br>
<br>
John<br>
<br>
On 14/05/18 00:57, James Howey wrote:<br>
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<p class="MsoNormal">Attached lp comes up infeasible in cbc, but
finds optimal objective in cplex. In cbc I ran it with and
without preprocessing which has given me problems before.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I ran latest trunk build and an older one.
I saw one checkin in latest saying SOS shouldn’t have
tolerance, and wonder if this is another similar
manifestation.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">It looks like it is correctly computing l1
(63999/64000), but then rounding l2 (1/64000 = 1.5625e-5) down
to zero. It would seem that a consistent rounding strategy
would yield a feasible solution. If it doesn’t admit l2 =
1.5625e-5 to the solution, it shouldn’t let l4 = 1.5930576e-09
in . If it rounds l2 = 1.5625e-5 to zero, it should round l1 =
.99998089 to 1.0. I would prefer no tolerance.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">X0009905: S2:: HS_ST(0)_l1:1 HS_ST(0)_l2:2
HS_ST(0)_l3:3 HS_ST(0)_l4:4<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Integer infeasible - objective value
0.00000000<o:p></o:p></p>
<p class="MsoNormal"> 10 HS_ST(0)_l1
0.99998089 0<o:p></o:p></p>
<p class="MsoNormal"> 11 HS_ST(0)_l2
0 0<o:p></o:p></p>
<p class="MsoNormal"> 12 HS_ST(0)_l3
1.9106687e-05 0<o:p></o:p></p>
<p class="MsoNormal"> 13 HS_ST(0)_l4
1.5930576e-09 0<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">In the meantime, can anyone suggest a
workaround?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">jkh<o:p></o:p></p>
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