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Hi Marko,<br>
<br>
can you explain the meaning of the 6th, 7th, and 8th column? I think
the last column is the gap?! Are you sure, that you have an feasible
solution, because you have an infinite gap which means (i) no primal
solution exists or (ii) primal or dual bound is equal to 0.<br>
<br>
Just as a remark, the gap set with the parameter "limits/gap" is
relative to 1, e.g., 1 corresponds to 100%.<br>
<br>
Best,<br>
Jakob <br>
<br>
<div class="moz-cite-prefix">On 25.09.2015 12:21, Horváth Markó
wrote:<br>
</div>
<blockquote cite="mid:56052044.3030408@gmail.com" type="cite">
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Dear all,<br>
<br>
I'm using SCIP-3.2.0 and I'm dealing with a branch-and-cut
procedure, and I set gaplimit to 0.005 (that is, "limits/gap" was
set to 0.005). Here is my output:<br>
<br>
<i>> (...)</i><br>
<i>> 35.0 1 38r 663 663 6913.000 --
6924.000 Inf</i><i><br>
</i><i>> (pricing) no new column(s)</i><i><br>
</i><i>> (general event handler) [lpsolved] LP of node 1 was
completely solved with cut & price</i><i><br>
</i><i>> (branching) branching at node 1</i><i><br>
</i><i>> (branching) branching node: 1 same node: 2 diff node:
3</i><i><br>
</i><i>> (general event handler) [nodebranched] the focus node
1 has been solved by branching</i><i><br>
</i><i>> problem has been solved with gap 0.0016</i><br>
<i>> (...)<br>
</i> <br>
In this output you can see that after some iterations my pricer
could not find new columns (hence my pricer sets result to
RESULT_SUCCESS), and SCIP says that the LP of node 1 was
completely solved with cut & price<i>.<br>
</i>So the root lowerbound is equal to 6913.000 and we also have a
primal solution with value 6924.000. So we have reached the
gaplimit at the root node, but as you can see SCIP didn't
terminate but performed a branching (actually using my branching
rule). It's not a big deal, but I wonder if we could avoid this <span
id="result_box" class="short_text" lang="en"><span class="hps">unnecessary
</span></span>step (i.e., we could check gap limit after a node
is solved with cut & price).<br>
<br>
Best regards,<br>
Marko<br>
<br>
<br>
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<br>
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</blockquote>
<span class="moz-txt-tag">-- <br>
</span>Jakob Witzig
<br>
<br>
Konrad-Zuse-Zentrum für
<br>
Informationstechnik Berlin (ZIB)
<br>
<br>
Division Mathematical Optimization and Scientific Information
<br>
Research Group Mathematical Optimization Methods
<br>
<br>
Takustrasse 7
<br>
14195 Berlin
<br>
<br>
Tel. : +49 (0)30 84185-416
<br>
Fax : +49 (0)30 84185-269
<br>
email: <a class="moz-txt-link-abbreviated"
href="mailto:witzig@zib.de">witzig@zib.de</a>
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