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<div class="moz-cite-prefix">Modified in trunk (can be copied to
stable). Just for now I have left it as was unless GOMORY_LONG is
defined in configure. If anyone is interested they could see what
difference it makes (on my first test it was slower - but then
invalid cuts can be very powerful!). There may be some connection
with queries about accuracy of Gomory cuts in 2015
(GOMORY_RELAX_NUMBER).<br>
<br>
John Forrest <br>
<br>
<br>
On 16/05/17 10:47, Tobias Stengel wrote:<br>
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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I noticed an integer overflow in
CglGomory.cpp / nearestRational(double, int) lines 445 and
446. That specific MIP is solved correctly, but I have no idea
whether such an overflow can lead to wrong cuts that e.g. cut
off the optimal solution. Anyway integer overflow is undefined
behaviour in C/C++ and the returned fractional is not „near“
the input…<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">2 parameter sets for nearestRational that
lead to overflow can be found in the attached test program.
Does anyone know how nearestRational works and how the
overflow can be fixed properly?<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">Tobias<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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