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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">The majority of OsiXXX solvers handle LP and MIP under one interface.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">It would seem to me, a cleaner design might be to replace OsiClp and OsiCbc with an OsiCoin (which would call the appropriate Coin solver if LP [CLP] or MIP
[CBC]). And, as mentioned before, OsiCoin .solve or .branchAndBound should perform the same as CbcMain*.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> osi-bounces@list.coin-or.org [mailto:osi-bounces@list.coin-or.org]
<b>On Behalf Of </b>Matthew Galati<br>
<b>Sent:</b> Monday, February 21, 2011 2:23 PM<br>
<b>To:</b> osi@list.coin-or.org<br>
<b>Subject:</b> [Osi] OsiCbc, CbcMain<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-bottom:12.0pt">It seems that the best way to solve IPs from OSI with CBC is to use:<br>
CbcModel cbc(*m_osi);<br>
CbcMain0(cbc);<br>
CbcMain1(argc, argv, cbc);<br>
<br>
This has been discussed many times, since OsiCbc/Clp.branchAndBound( ) doesn't do all the tricks and performs poorly.<br>
<br>
But, I just noticed today, that CbcModel cbc(*m_osi) works only with OsiClp and not with OsiCbc. That seems very odd to me - since Osi is suppose to be the container with which you would hold an IP and you would only drop to Cbc* when something in Osi does
not work properly (similar to dropping out of OsiCpx to CPX* when something in OsiCpx is missing).<br>
<br>
Shouldn't CbcModel/Main work with OsiCbc?<br>
<br>
Matt<o:p></o:p></p>
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