No subject
Wed Sep 26 11:31:34 EDT 2012
1. Import MPS file by just typing "import mpsfilename.mps" 2. and then you =
can solve it just typing "branchAndCut"
Then compare the time to solve with the API.
A random google search to find a "recipe" could be (at the end of page 6): =
http://wpweb2.tepper.cmu.edu/fmargot/coin/proj5.pdf
Regards
Date: Tue=2C 9 Oct 2012 20:50:04 +0300
From: chtsolak at gmail.com
To: dibarra21 at hotmail.com
CC: cbc at list.coin-or.org
Subject: Re: [Cbc] solving time in C++ >> time in Gams
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i have the latest version=2C 2.7.7....
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I solve it by using the default cbc solver=2C (i am not getting
involved in the solver) with this way:
=20
solver1.loadProblem(numcols=2C numrows=2C start=2C index=2C
value=2C collb=2C colub=2C obj=2C rowlb=2C rowub)=3B
CbcModel model(solver1)=3B
CbcMain0(model)=3B
const char * argv2[]=3D{"DAS"=2C"-solve"=2C"-quit"}=3B =20
=20
CbcMain1(3=2Cargv2=2Cmodel)=3B =20
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So=2C i do not think that it's ommiting the presolve step=2C am i
wrong?
=20
Where can i find the latest version=2C and how can i load an mps
file?
=20
Thank you
=20
On 9/10/2012 20:42=2C David Ibarra G=F3mez wrote:
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Hi=2C
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there are several things that can cause this:
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different solvers version=2C
solving is a complex task: presolve (cuting planes=2C heuristic=
s=2C ...) and then branch and bound (cut). If you
omit the first part or you do not do exactly the same
steps result could be different.
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Did you try to solve using CBC CLI (stand alone executable) ?
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Regards
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Date: Tue=2C 9 Oct 2012 12:16:49 +0300
From: chtsolak at gmail.com
To: cbc at list.coin-or.org
Subject: [Cbc] solving time in C++ >> time in Gams
=20
Hi all again=2C
=20
I have 1 question for you=2C if i solve it=2C i won't bother
you again :-P=20
=20
I am using cbc in order to make an executable via MS visual
studio which solves a model.
In order to solve it=2C takes 60 mins
=20
I have made the same problem with GAMS and solved it in 30
secs=2C 120 times faster!!
=20
Is it because of an error in modeling or due to the
different interface? (exe-GAMS)
=20
Why is there this enormous difference?
=20
=20
Thank you in advance.
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=20
_______________________________________________
Cbc mailing list
Cbc at list.coin-or.org
http://list.coin-or.org/mailman/listinfo/cbc
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=
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<body class=3D'hmmessage'><div dir=3D'ltr'>
You can find the CBC binaries here: =3B<a href=3D"https://projects.coin=
-or.org/CoinBinary">https://projects.coin-or.org/CoinBinary</a> =3Bor (=
here =3B<a href=3D"http://www.coin-or.org/download/binary/Cbc/">http://=
www.coin-or.org/download/binary/Cbc/</a>). You can test different versions<=
div><br></div><div>From the shell you can call the executable binary. Then =
you just:</div><div><br></div><div>1. Import MPS file by just typing "impor=
t mpsfilename.mps" =3B</div><div>2. and then you can solve it just typi=
ng "branchAndCut"</div><div><br></div><div>Then compare the time to solve w=
ith the API.</div><div><br></div><div>A random google search to find a "rec=
ipe" could be (at the end of page 6): =3B<a href=3D"http://wpweb2.teppe=
r.cmu.edu/fmargot/coin/proj5.pdf" style=3D"font-size: 10pt=3B ">http://wpwe=
b2.tepper.cmu.edu/fmargot/coin/proj5.pdf</a></div><div><br></div><div>Regar=
ds</div><div><div><br></div><div><br><br><div><div id=3D"SkyDrivePlaceholde=
r"></div><hr id=3D"stopSpelling">Date: Tue=2C 9 Oct 2012 20:50:04 +0300<br>=
From: chtsolak at gmail.com<br>To: dibarra21 at hotmail.com<br>CC: cbc at list.coin-=
or.org<br>Subject: Re: [Cbc] solving time in C++ >=3B>=3B time in Gams=
<br><br>
=20
=20
=20
=20
<div class=3D"ecxmoz-cite-prefix">i have the latest version=2C 2.7.7...=
.<br>
<br>
I solve it by using the default cbc solver=2C (i am not getting
involved in the solver) with this way:<br>
<br>
<i><small>solver1.loadProblem(numcols=2C numrows=2C start=2C index=2C
value=2C collb=2C colub=2C obj=2C rowlb=2C rowub)=3B<br>
CbcModel model(solver1)=3B<br>
CbcMain0(model)=3B<br>
const char * argv2[]=3D{"DAS"=2C"-solve"=2C"-quit"}=3B =3B&nb=
sp=3B
</small></i><i><small><br>
CbcMain1(3=2Cargv2=2Cmodel)=3B =3B =3B =3B
</small></i><br>
<br>
So=2C i do not think that it's ommiting the presolve step=2C am i
wrong?<br>
<br>
Where can i find the latest version=2C and how can i load an mps
file?<br>
<br>
Thank you<br>
<br>
On 9/10/2012 20:42=2C David Ibarra G=F3mez wrote:<br>
</div>
<blockquote cite=3D"mid:DUB121-W264ACA45902B3CC4C2E78A38F0 at phx.gbl">
<style><!--
.ExternalClass .ecxhmmessage P
{padding:0px=3B}
.ExternalClass body.ecxhmmessage
{font-size:10pt=3Bfont-family:Tahoma=3B}
--></style>
<div dir=3D"ltr">
Hi=2C
<div><br>
</div>
<div>there are several things that can cause this:</div>
<div><br>
</div>
<div>
<ul>
<li>different solvers version=2C</li>
<li>solving is a complex task: =3B<span style=3D"font-size:=
10pt">presolve (cuting planes=2C heuristics=2C ...) and then b</span><span =
style=3D"font-size:10pt">ranch and bound (cut). If you
omit the first part or you do not do exactly the same
steps result could be different.</span></li>
</ul>
<div><br>
</div>
Did you try to solve using CBC CLI (stand alone executable) ?</di=
v>
<div><br>
</div>
<div>Regards<br>
<br>
<div>
<hr id=3D"ecxstopSpelling">Date: Tue=2C 9 Oct 2012 12:16:49 +03=
00<br>
From: <a class=3D"ecxmoz-txt-link-abbreviated" href=3D"mailto:c=
htsolak at gmail.com">chtsolak at gmail.com</a><br>
To: <a class=3D"ecxmoz-txt-link-abbreviated" href=3D"mailto:cbc=
@list.coin-or.org">cbc at list.coin-or.org</a><br>
Subject: [Cbc] solving time in C++ >=3B>=3B time in Gams<br=
>
<br>
Hi all again=2C<br>
<br>
I have 1 =3B question for you=2C if i solve it=2C i won't b=
other
you again <span class=3D"ecxmoz-smiley-s4"><span> :-P </span></=
span><br>
<br>
I am using cbc in order to make an executable via MS visual
studio which solves a model.<br>
In order to solve it=2C takes 60 mins<br>
<br>
I have made the same problem with GAMS and solved it in 30
secs=2C 120 times faster!!<br>
<br>
Is it because of an error in modeling or due to the
different interface? (exe-GAMS)<br>
<br>
Why is there this enormous difference?<br>
<br>
<br>
Thank you in advance.<i><small><i><small><br>
</small></i></small></i><br>
<i><small><i><small><br>
</small></i><br>
</small></i> <br>
_______________________________________________
Cbc mailing list
<a class=3D"ecxmoz-txt-link-abbreviated" href=3D"mailto:Cbc at lis=
t.coin-or.org">Cbc at list.coin-or.org</a>
<a class=3D"ecxmoz-txt-link-freetext" href=3D"http://list.coin-=
or.org/mailman/listinfo/cbc" target=3D"_blank">http://list.coin-or.org/mail=
man/listinfo/cbc</a></div>
</div>
</div>
</blockquote>
<br></div></div></div> </div></body>
</html>=
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