<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:x="urn:schemas-microsoft-com:office:excel" xmlns:p="urn:schemas-microsoft-com:office:powerpoint" xmlns:a="urn:schemas-microsoft-com:office:access" xmlns:dt="uuid:C2F41010-65B3-11d1-A29F-00AA00C14882" xmlns:s="uuid:BDC6E3F0-6DA3-11d1-A2A3-00AA00C14882" xmlns:rs="urn:schemas-microsoft-com:rowset" xmlns:z="#RowsetSchema" xmlns:b="urn:schemas-microsoft-com:office:publisher" xmlns:ss="urn:schemas-microsoft-com:office:spreadsheet" xmlns:c="urn:schemas-microsoft-com:office:component:spreadsheet" xmlns:odc="urn:schemas-microsoft-com:office:odc" xmlns:oa="urn:schemas-microsoft-com:office:activation" xmlns:html="http://www.w3.org/TR/REC-html40" xmlns:q="http://schemas.xmlsoap.org/soap/envelope/" xmlns:D="DAV:" xmlns:x2="http://schemas.microsoft.com/office/excel/2003/xml" xmlns:ois="http://schemas.microsoft.com/sharepoint/soap/ois/" xmlns:dir="http://schemas.microsoft.com/sharepoint/soap/directory/" xmlns:ds="http://www.w3.org/2000/09/xmldsig#" xmlns:dsp="http://schemas.microsoft.com/sharepoint/dsp" xmlns:udc="http://schemas.microsoft.com/data/udc" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:sub="http://schemas.microsoft.com/sharepoint/soap/2002/1/alerts/" xmlns:ec="http://www.w3.org/2001/04/xmlenc#" xmlns:sp="http://schemas.microsoft.com/sharepoint/" xmlns:sps="http://schemas.microsoft.com/sharepoint/soap/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:udcxf="http://schemas.microsoft.com/data/udc/xmlfile" xmlns:wf="http://schemas.microsoft.com/sharepoint/soap/workflow/" xmlns:mver="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns:mrels="http://schemas.openxmlformats.org/package/2006/relationships" xmlns:ex12t="http://schemas.microsoft.com/exchange/services/2006/types" xmlns:ex12m="http://schemas.microsoft.com/exchange/services/2006/messages" xmlns:Z="urn:schemas-microsoft-com:" xmlns:st="" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv=Content-Type content="text/html; charset=us-ascii">
<meta name=Generator content="Microsoft Word 12 (filtered medium)">
<style>
<!--
/* Font Definitions */
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0cm;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman","serif";}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
p
{mso-style-priority:99;
mso-margin-top-alt:auto;
margin-right:0cm;
mso-margin-bottom-alt:auto;
margin-left:0cm;
font-size:12.0pt;
font-family:"Times New Roman","serif";}
tt
{mso-style-priority:99;
font-family:"Courier New";}
span.EmailStyle19
{mso-style-type:personal-reply;
font-family:"Calibri","sans-serif";
color:#1F497D;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;}
@page Section1
{size:612.0pt 792.0pt;
margin:72.0pt 72.0pt 72.0pt 72.0pt;}
div.Section1
{page:Section1;}
-->
</style>
<!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body lang=EN-US link=blue vlink=purple>
<div class=Section1>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Hi,<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>I have some questions about WarmStarts using OsiClp. <o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>I'm solving pure LPs and I tried to recreate my real problem using
miplib 3.0s "p0548" (See <a
href="http://www.caam.rice.edu/~bixby/miplib/miplib3.html">http://www.caam.rice.edu/~bixby/miplib/miplib3.html</a>)<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>See below for code and output.<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Basically, I (1) solve the problem, store a warm start, (2) change
the objective and resolve, and (3) restore original objecte, load warmstart and
resolve.<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>I was expecting the step (3) to take zero iterations. However,
this is not (always) the case: In this test problem, <o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Test run 1) if I do NOT set hints concerning DoDualIn*, then
indeed (3) takes zero iterations.<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Test run 2) but if I set HintTry for these to false (so use
primal), then (3) reoptimises (see end of email)<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>In my real instances the (3) resolve takes a *lot* of
iterations.<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Note that this test problem doesn’t completely represent
my real problem: the real instances show this behaviour even <i>without</i> the
DoDual = false settings, but the resulting iterations are the same.<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>What could be the cause for these reoptimizations?<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>A) different algorithm after warmstart compared to solve
warmstart was based on?<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>B) presolve chooses to remove different rows/columns in resolve?<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>C) something else?<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Or is this simply not what the warmstarts are for?<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Any help would be appreciated.<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Regards,<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Jan-Wilem Goossens<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>————————————————————--<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Here is the test problem<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> OsiClpSolverInterface
model;<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> <o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> model.setHintParam(OsiHintParam::OsiDoDualInInitial,
<span style='color:blue'>false</span>); <span style='color:green'>// comment
out<o:p></o:p></span></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> model.setHintParam(OsiHintParam::OsiDoDualInResolve,
<span style='color:blue'>false</span>); <span style='color:green'>// comment
out</span><o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> model.setHintParam(OsiHintParam::OsiDoPresolveInInitial);<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> model.setHintParam(OsiHintParam::OsiDoPresolveInResolve);<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> <span
style='color:blue'>int</span> status = model.readMps(<span style='color:#A31515'>"p0548.mps"</span>,
<span style='color:blue'>true</span>, <span style='color:blue'>false</span>);<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> <span
style='color:blue'>int</span> n = model.getNumCols();<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> <span
style='color:blue'>for</span> (<span style='color:blue'>int</span> i = 0; i
< n; i++) model.setContinuous(i); <span style='color:green'>// change to LP</span><o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> <span
style='color:green'>// (1) do initial solve of original problem, and store warm
start info<o:p></o:p></span></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> model.initialSolve();<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> CoinWarmStart
*warmStart = model.getWarmStart();<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> <span
style='color:green'>// (2) change the objective function and resolve<o:p></o:p></span></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> <span
style='color:blue'>const</span> <span style='color:blue'>double</span> *
objCoefs = model.getObjCoefficients();<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> <span
style='color:blue'>double</span> * oldCoefs = <span style='color:blue'>new</span>
<span style='color:blue'>double</span>[n];<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> <span
style='color:blue'>for</span> (<span style='color:blue'>int</span> i = 0; i
< n; i++) oldCoefs[i] = objCoefs[i];<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> <span
style='color:blue'>for</span> (<span style='color:blue'>int</span> i = 0; i
< n; i++) model.setObjCoeff(i,1.0);<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> model.resolve();<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'><o:p> </o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> <span
style='color:green'>// (3) restore the original problem, and load warm start<o:p></o:p></span></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> model.setObjective(oldCoefs);<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> model.setWarmStart(warmStart);<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'> model.resolve();<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>OUTPUT:<o:p></o:p></span></p>
<p class=MsoNormal><b><span lang=EN-GB style='font-size:11.0pt;font-family:
"Calibri","sans-serif";color:#1F497D'>Test run 1, with commented out:<o:p></o:p></span></b></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> // model.setHintParam(OsiHintParam::OsiDoDualInInitial,
<span style='color:blue'>false</span>); <span style='color:green'>// comment
out<o:p></o:p></span></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> // model.setHintParam(OsiHintParam::OsiDoDualInResolve,
<span style='color:blue'>false</span>); <span style='color:green'>// comment
out</span><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> <span
style='color:green'>// (1) do initial solve of original problem, and store warm
start info<o:p></o:p></span></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Coin0506I Presolve 163 (-13) rows, 543 (-5) columns and 1561
(-150) elements<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0006I 0 Obj 0 Primal inf 38.8018 (12)<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0006I 95 Obj 315.255<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0000I Optimal - objective value 315.255<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Coin0511I After Postsolve, objective 315.255, infeasibilities -
dual 0 (0), primal 0 (0)<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0006I 0 Obj 315.255<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0006I 0 Obj 315.255<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0000I Optimal - objective value 315.255<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> <span
style='color:green'>// (2) change the objective function and resolve<o:p></o:p></span></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Coin0506I Presolve 165 (-11) rows, 543 (-5) columns and 1579
(-132) elements<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0006I 0 Obj 59.3381 Primal inf 0.314674 (1) Dual inf
161381 (290)<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0006I 103 Obj 16.571 Primal inf 8.57907 (29)<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0006I 165 Obj 26.1669<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0000I Optimal - objective value 26.1669<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Coin0511I After Postsolve, objective 26.1669, infeasibilities -
dual 0 (0), primal 0 (0)<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> <span
style='color:green'>// (3) restore the original problem, and load warm start<o:p></o:p></span></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Coin0506I Presolve 163 (-13) rows, 543 (-5) columns and 1561
(-150) elements<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0006I 0 Obj 366.255 Primal inf 30.9296 (2) Dual inf
304.123 (2)<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0000I Optimal - objective value 315.255<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Coin0511I After Postsolve, objective 315.255, infeasibilities -
dual 0 (0), primal 0 (0)<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><b><span lang=EN-GB style='font-size:11.0pt;font-family:
"Calibri","sans-serif";color:#1F497D'>Test run 2, with:<o:p></o:p></span></b></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> model.setHintParam(OsiHintParam::OsiDoDualInInitial,
<span style='color:blue'>false</span>); <span style='color:green'><o:p></o:p></span></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> model.setHintParam(OsiHintParam::OsiDoDualInResolve,
<span style='color:blue'>false</span>); <o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> <span
style='color:green'>// (1) do initial solve of original problem, and store warm
start info<o:p></o:p></span></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Coin0506I Presolve 163 (-13) rows, 543 (-5) columns and 1561
(-150) elements<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0028I Crash put 44 variables in basis, 0 dual infeasibilities<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0006I 0 Obj 0 Primal inf 38.8018 (12) Dual inf
5.62868e+012 (120)<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0006I 132 Obj 20103.2 Primal inf 1.08159 (1) Dual inf
1.10445e+011 (193)<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0006I 289 Obj 345.667 Dual inf 627.385 (26)<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0006I 316 Obj 315.255<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0000I Optimal - objective value 315.255<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Coin0511I After Postsolve, objective 315.255, infeasibilities -
dual 0 (0), primal 0 (0)<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0006I 0 Obj 315.255<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0006I 0 Obj 315.255<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0000I Optimal - objective value 315.255<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> <span
style='color:green'>// (2) change the objective function and resolve<o:p></o:p></span></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Coin0506I Presolve 165 (-11) rows, 543 (-5) columns and 1579
(-132) elements<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0006I 0 Obj 69.5868 Dual inf 38838.5 (125)<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0006I 94 Obj 26.1669<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Clp0000I Optimal - objective value 26.1669<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Coin0511I After Postsolve, objective 26.1669, infeasibilities -
dual 0 (0), primal 0 (0)<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Coin0506I Presolve 163 (-13) rows, 543 (-5) columns and 1561
(-150) elements<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Courier New"'> <span
style='color:green'>// (3) restore the original problem, and load warm start<o:p></o:p></span></span></p>
<p class=MsoNormal><b><span lang=EN-GB style='font-size:11.0pt;font-family:
"Calibri","sans-serif";color:#1F497D'>Clp0006I 0 Obj 1817.67 Dual inf
3514.68 (6)<o:p></o:p></span></b></p>
<p class=MsoNormal><b><span lang=EN-GB style='font-size:11.0pt;font-family:
"Calibri","sans-serif";color:#1F497D'>Clp0029I End of values pass after 37
iterations<o:p></o:p></span></b></p>
<p class=MsoNormal><b><span lang=EN-GB style='font-size:11.0pt;font-family:
"Calibri","sans-serif";color:#1F497D'>Clp0006I 37 Obj 1817.67 Dual inf
3515.85 (5)<o:p></o:p></span></b></p>
<p class=MsoNormal><b><span lang=EN-GB style='font-size:11.0pt;font-family:
"Calibri","sans-serif";color:#1F497D'>Clp0006I 170 Obj 336.741 Dual inf
20.3286 (24)<o:p></o:p></span></b></p>
<p class=MsoNormal><b><span lang=EN-GB style='font-size:11.0pt;font-family:
"Calibri","sans-serif";color:#1F497D'>Clp0006I 202 Obj 315.255<o:p></o:p></span></b></p>
<p class=MsoNormal><b><span lang=EN-GB style='font-size:11.0pt;font-family:
"Calibri","sans-serif";color:#1F497D'>Clp0000I Optimal - objective value
315.255<o:p></o:p></span></b></p>
<p class=MsoNormal><b><span lang=EN-GB style='font-size:11.0pt;font-family:
"Calibri","sans-serif";color:#1F497D'>Coin0511I After Postsolve, objective
315.255, infeasibilities - dual 0 (0), primal 0 (0)<o:p></o:p></span></b></p>
<p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
</div>
</body>
</html>