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<div class="moz-cite-prefix">Mattia,<br>
<br>
Really for flexibility you need to write an event handler (see
examples in Cbc/examples) - but one parameter is maxnodes. Better
yet is to also add ratiogap or allowablegap to stop when
reasonable solution.<br>
<br>
Your problem has a lot of symmetry - see if you can break that
symmetry.<br>
<br>
Optimal answer is 23652.0 - which code gets quite soon - so doing<br>
<br>
cbc payg_final.mod%inp-2395.dat -ratiogap 0.01 -solve<br>
<br>
gives<br>
<br>
Result - Optimal solution found (within gap tolerance)<br>
<br>
Objective value: 23652.00000000<br>
Lower bound: 23587.000<br>
Time 299.32 seconds<br>
<br>
John Forrest<br>
<br>
On 27/09/14 07:38, Mattia Buccarella wrote:<br>
</div>
<blockquote
cite="mid:CAE5kHDkcuhW-fE8a=8-74P0atE4dQsNA0zkNU+4UOHOGTzANAw@mail.gmail.com"
type="cite">
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<div>
<div>
<div>Hello everyone.<br>
<br>
I am using the standalone Cbc 2.8.9, compiled with the GNU
MathProg support.<br>
I have the problem that it gets stuck forever on certain
MILP instances.<br>
<br>
</div>
<div>One of these instance can be found at the following
url:<br>
</div>
<div>INSTANCE: <a moz-do-not-send="true"
href="https://dl.dropboxusercontent.com/u/44504233/inp-2395.dat">https://dl.dropboxusercontent.com/u/44504233/inp-2395.dat</a><br>
</div>
<div>MODEL: <a moz-do-not-send="true"
href="https://dl.dropboxusercontent.com/u/44504233/payg_final.mod">https://dl.dropboxusercontent.com/u/44504233/payg_final.mod</a><br>
</div>
<div><br>
I tried with the<br>
<br>
-cuts on<br>
<br>
</div>
option to see if something changed but the result was the
same, and now I don't know what to try. I tried the options
-nodelim and -nodlim to see if I could stop it after a
while, but it did not look working.<br>
<br>
</div>
At the moment, I really need it to stop after spending some
time on a certain solution. Do you know how could I do it? The
only required thing is that, when I stop it, the found
solution (partial) should still be feasible. So optimality is
not fundamental at the moment. Feasibility it is instead.<br>
<br>
Thank you very much for your time.<br>
<br>
--<br>
</div>
Mattia Buccarella<br>
</div>
<br>
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