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<div class="moz-cite-prefix">Dear Vladimir,<br>
<br>
<code>Stefan Vigerske and I tried to implement it so that it works
more precisely.<br>
Probably, the code is already released in the version.<br>
Please try to use the command line option with "-sl gap.set",
and the file gap.set inclueds<br>
"limits/gap" or "limits/absgap". Then, it would work better than
the previous versions.<br>
Please let me know the results.<br>
</code><code>@Stefan: If you can say something else, please add
your comments. <br>
<br>
Best regards,<br>
Yuji<br>
</code><br>
On 24.04.23 1:06, Vladimir V. Voloshinov wrote:<br>
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cite="mid:CAH87KpvxK-3546HWFp6PeNfSzza0LKRBQZcXeEpVTcdGP1zT=w@mail.gmail.com">
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<div>Dear Yuji,<br>
</div>
excuse for bothering you, but I see that SCIP Opt. Suite 8.0.3
includes UG 1.0 already. <br>
<div>I see that the parameter CheckGapInLC, which we tried to
use, has been excluded from the list of UG options, so it
seems that some changes with "gap management" happened...</div>
<div>But I see that the gap set in the scip.set file does not
affect FiberSCIP which still solves problem till zero gap. <br>
Moreover, I see in ug/src/ug_scip/scipParaSolver.cpp, lines
#1259,#1260, that "limits/gap" and "limits/absgap" are
"hardcoded" to be 0...<br>
</div>
<div>Maybe we missed something, but is it possible to set a non
zero gap for FiberSCIP (and ParaSCIP) now, since version
8.0.3? It is very important in some circumstances...<br>
</div>
<div><br>
</div>
<div>Best regards,<br>
</div>
<div>Vladimir<br>
</div>
</div>
<br>
<div class="gmail_quote">
<div dir="ltr" class="gmail_attr">On Mon, Sep 12, 2022 at
5:36 PM Yuji Shinano <<a href="mailto:shinano@zib.de"
moz-do-not-send="true" class="moz-txt-link-freetext">shinano@zib.de</a>>
wrote:<br>
</div>
<blockquote class="gmail_quote" style="margin:0px 0px 0px
0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Hi
Sergey,<br>
<br>
On 12.09.22 16:17, Sergey Smirnov wrote:<br>
> Thank you for checking my instance.<br>
><br>
> We also tried setting CheckGapInLC=TRUE but it did not
help either.<br>
<br>
Thanks for testing it, too. Probably, I tried to implement it
once,<br>
but I had some issues realizing it. Before UG version 1.0,<br>
UG was a bit hard to specialize for a specific "base solver"
parallelization.<br>
In current UG version 1.0, it is easy to implement some
features<br>
specialized to a specific "base solver".<br>
I will let you know when I add the feature to FiberSCIP and
ParaSCIP.<br>
<br>
Best,<br>
Yuji<br>
<br>
><br>
>> On 11 Sep 2022, at 17:42, Yuji Shinano <<a
href="mailto:shinano@zib.de" target="_blank"
moz-do-not-send="true" class="moz-txt-link-freetext">shinano@zib.de</a>>
wrote:<br>
>><br>
>> Hi Sergey,<br>
>><br>
>> Thanks for the instance and configuration. I checked
it.<br>
>> Sorry, in the current implementation of FiberSCIP and
ParaSCIP, controlling it only with the SCIP parameter looks
difficult when it takes time to solve<br>
>> (if it can be solved in the racing stage, the
"NoPreprocessingInLC = TRUE" might work).<br>
>> And it looks like the setting SCIP parameters for
that is not good for FiberSCIP and ParaSCIP in a sense how it
work is not clear.<br>
>> I will add the feature rather UG side in the future.
I think it can not control vividly, but when LC recognized
that gap is reached,<br>
>> then LC interrupts all computations from the UG side.<br>
>><br>
>> Best regards,<br>
>> Yuji<br>
>><br>
>> --------------<br>
>> Hi Yuji,<br>
>><br>
>> Here are the instance and configuration files
attached.<br>
>><br>
>> Thank you in advance,<br>
>> Best regards,<br>
>> Sergey<br>
>><br>
>><br>
>> > On 10 Sep 2022, at 08:55, Yuji Shinano <<a
href="mailto:shinano@zib.de" target="_blank"
moz-do-not-send="true" class="moz-txt-link-freetext">shinano@zib.de</a>>
wrote:<br>
>> ><br>
>> > Hi Sergey,<br>
>> ><br>
>> > Can you send me the instance and parameters (UG
and SCIP)? I will check it.<br>
>> ><br>
>> > Best regards,<br>
>> > Yuji<br>
>> ><br>
>> > On 10.09.22 6:50, Sergey Smirnov wrote:<br>
>> >> Hi Yuji,<br>
>> >><br>
>> >> Thank you for the suggestion. I tried to set
NoPreprocessingInLC = TRUE in ug.set but both fscip and
parascip still solved till zero gap.<br>
>> >><br>
>> >> Best regards,<br>
>> >> Sergey<br>
>> >><br>
>> >>> On 9 Sep 2022, at 21:20, Yuji Shinano
<<a href="mailto:shinano@zib.de" target="_blank"
moz-do-not-send="true" class="moz-txt-link-freetext">shinano@zib.de</a>>
wrote:<br>
>> >>><br>
>> >>> Hi,<br>
>> >>><br>
>> >>> This is one of the frequently asked
questions. FiberSCIP/ParaSCIP solves the presolved instance in
the Solvers.<br>
>> >>> Therefore, the value is applied to solve
the presolved instance. If you would like to control the gap
more precisely,<br>
>> >>> one way would be to set<br>
>> >>> NoPreprocessingInLC = TRUE<br>
>> >>> In the UG parameter file.<br>
>> >>> However, this means that layered
presolving does not work and may decrease its performance.<br>
>> >>> Please try to run with the above
parameter.<br>
>> >>><br>
>> >>> Best,<br>
>> >>> Yuji<br>
>> >>><br>
>><br>
>><br>
>> On 09.09.22 19:45, Sergey Smirnov wrote:<br>
>>> Hello, SCIP community,<br>
>>><br>
>>> I have problems setting relative gap in parallel
version of SCIP 8.0.1.<br>
>>><br>
>>> When I set limits/gap = .5e-01 in scip.set and
run scip like scip -f problem.cip -s scip.set scip stops
after reaching the gap specified. However, fscip and parascip
seem to ignore this parameter. For example, I run fscip the
following way and it solves until optimality:<br>
>>> fscip ug.set problem.cip -s scip.set<br>
>>><br>
>>> What is the correct way to set relative gap in
fscip/parascip?<br>
>>><br>
>>> Thank you in advance,<br>
>>> Best regards,<br>
>>> Sergey<br>
>>><br>
>>><br>
>>> _______________________________________________<br>
>>> Scip mailing list<br>
>>> <a href="mailto:Scip@zib.de" target="_blank"
moz-do-not-send="true" class="moz-txt-link-freetext">Scip@zib.de</a><br>
>>> <a
href="https://listserv.zib.de/mailman/listinfo/scip"
rel="noreferrer" target="_blank" moz-do-not-send="true"
class="moz-txt-link-freetext">https://listserv.zib.de/mailman/listinfo/scip</a><br>
>><br>
>><br>
>> -- <br>
>> --------------------------------------------------<br>
>> Yuji Shinano<br>
>> Zuse Institute Berlin<br>
>> Takustrasse 7, 14195 Berlin-Dahlem, Germany<br>
>> Phone:+49 30 84185-477, Fax:+49 30 84185-269<br>
>><br>
>> _______________________________________________<br>
>> Scip mailing list<br>
>> <a href="mailto:Scip@zib.de" target="_blank"
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rel="noreferrer" target="_blank" moz-do-not-send="true"
class="moz-txt-link-freetext">https://listserv.zib.de/mailman/listinfo/scip</a><br>
><br>
<br>
<br>
-- <br>
--------------------------------------------------<br>
Yuji Shinano<br>
Zuse Institute Berlin<br>
Takustrasse 7, 14195 Berlin-Dahlem, Germany<br>
Phone:+49 30 84185-477, Fax:+49 30 84185-269<br>
<br>
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<span class="gmail_signature_prefix">-- </span><br>
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<div>Vladimir V. Voloshinov,<br>
Ph.D, head of lab. C-3 "Distributed computing
algorithms", <a
href="http://www.iitp.ru/ru/researchlabs/1040.htm"
target="_blank" moz-do-not-send="true"
class="moz-txt-link-freetext">http://www.iitp.ru/ru/researchlabs/1040.htm</a>,<br>
Center for Distributed Computing, Institute for
Information Transmission Problems RAS, <a
href="http://www.iitp.ru" target="_blank"
moz-do-not-send="true"
class="moz-txt-link-freetext">http://www.iitp.ru</a><br>
web: <a
href="https://scholar.google.ru/citations?hl=en&user=-m4QhNEAAAAJ&view_op=list_works&sortby=pubdate"
target="_blank" moz-do-not-send="true">GoogleScholar
profile</a></div>
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</blockquote>
<br>
<br>
<pre class="moz-signature" cols="0">--
--------------------------------------------------
Yuji Shinano
Zuse Institute Berlin
Takustrasse 7, 14195 Berlin-Dahlem, Germany
Phone:+49 30 84185-477, Fax:+49 30 84185-269</pre>
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