John,<br><br>Tried using the setMustCallAgain(true) to my cut generator, but the problem continues.<br><br>Haroldo<br><br><div class="gmail_quote">On Wed, May 21, 2008 at 7:05 AM, John J Forrest <<a href="mailto:jjforre@us.ibm.com">jjforre@us.ibm.com</a>> wrote:<br>
<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"><div>
<p>Haroldo,<br>
<br>
There may be bugs in the code but I think that you need to change some of the options in the CbcCutGenerator before you pass it to Cbc. In particular setMustCallAgain(true) will say keep adding cuts as long as there are any.<br>
<br>
The deafult will stop after a few passes, which is probably why you are seeing what is happening.<br>
<br>
John Forrest<br>
<br>
<img src="cid:1__=0ABBFEC3DFA4BEE68f9e8a93df938@us.ibm.com" alt="Inactive hide details for "Haroldo Santos" ---05/20/2008 09:23:52 AM---Hi All," border="0" height="16" width="16"><font color="#424282">"Haroldo Santos" ---05/20/2008 09:23:52 AM---Hi All,</font><br>
<br>
</p><table border="0" cellpadding="0" cellspacing="0" width="100%">
<tbody><tr valign="top"><td width="1%"><img src="cid:2__=0ABBFEC3DFA4BEE68f9e8a93df938@us.ibm.com" alt="" border="0" height="1" width="96"><br>
<font color="#5f5f5f" size="2">From:</font></td><td width="100%"><img src="cid:2__=0ABBFEC3DFA4BEE68f9e8a93df938@us.ibm.com" alt="" border="0" height="1" width="1"><br>
<font size="2">"Haroldo Santos" <<a href="mailto:haroldo.santos@gmail.com" target="_blank">haroldo.santos@gmail.com</a>></font></td></tr>
<tr valign="top"><td width="1%"><img src="cid:2__=0ABBFEC3DFA4BEE68f9e8a93df938@us.ibm.com" alt="" border="0" height="1" width="96"><br>
<font color="#5f5f5f" size="2">To:</font></td><td width="100%"><img src="cid:2__=0ABBFEC3DFA4BEE68f9e8a93df938@us.ibm.com" alt="" border="0" height="1" width="1"><br>
<font size="2"><a href="mailto:cbc@list.coin-or.org" target="_blank">cbc@list.coin-or.org</a></font></td></tr>
<tr valign="top"><td width="1%"><img src="cid:2__=0ABBFEC3DFA4BEE68f9e8a93df938@us.ibm.com" alt="" border="0" height="1" width="96"><br>
<font color="#5f5f5f" size="2">Date:</font></td><td width="100%"><img src="cid:2__=0ABBFEC3DFA4BEE68f9e8a93df938@us.ibm.com" alt="" border="0" height="1" width="1"><br>
<font size="2">05/20/2008 09:23 AM</font></td></tr>
<tr valign="top"><td width="1%"><img src="cid:2__=0ABBFEC3DFA4BEE68f9e8a93df938@us.ibm.com" alt="" border="0" height="1" width="96"><br>
<font color="#5f5f5f" size="2">Subject:</font></td><td width="100%"><img src="cid:2__=0ABBFEC3DFA4BEE68f9e8a93df938@us.ibm.com" alt="" border="0" height="1" width="1"><br>
<font size="2">[Cbc] Cuts and Integer Solutions in CBC</font></td></tr>
</tbody></table>
<hr style="color: rgb(128, 145, 165);" align="left" noshade size="2" width="100%"><div><div></div><div class="Wj3C7c"><br>
<br>
<br>
<font size="4">Hi All,<br>
<br>
I'm working with a MIP with an exponential number of constraints. To define the problem we need this huge amount of rows.<br>
So, I defined a cbcmodel with a small subset of these constraints and added an specialization of CglCutGenerator to dynamically insert the other rows, as needed.<br>
However, in the first iterations cbcmodel finds an Integer solution and stops the search, even if new cuts were added.<br>
Note that these "cuts" are not cuts in the traditional way: they do not cut fractional solutions. Instead, they define the problem.<br>
Is there any way to tell cbc that if new cuts were added, it must continue the search ?<br>
I think that in CPLEX this can be done by the so called "lazy constraints".<br>
<br>
Best regards,<br>
<br>
Haroldo<br>
<br>
-- <br>
===============================================================<br>
Haroldo Gambini Santos</font><u><font color="#0000ff" size="4"><br>
</font></u><a href="http://www.ic.uff.br/%7Ehsantos" target="_blank"><u><font color="#0000ff" size="4">http://www.ic.uff.br/~hsantos</font></u></a><u><font color="#0000ff" size="4"><br>
</font></u><a href="mailto:hsantos@ic.uff.br" target="_blank"><u><font color="#0000ff" size="4">hsantos@ic.uff.br</font></u></a></div></div><font size="4"><br>
Instituto de Computacao - Universidade Federal Fluminense </font><tt>_______________________________________________<br>
Cbc mailing list<br>
<a href="mailto:Cbc@list.coin-or.org" target="_blank">Cbc@list.coin-or.org</a><br>
</tt><tt><a href="http://list.coin-or.org/mailman/listinfo/cbc" target="_blank">http://list.coin-or.org/mailman/listinfo/cbc</a></tt><tt><br>
</tt><br>
</div>
</blockquote></div><br><br clear="all"><br>-- <br>===============================================================<br>Haroldo Gambini Santos<br><a href="http://www.ic.uff.br/~hsantos">http://www.ic.uff.br/~hsantos</a><br>
<a href="mailto:hsantos@ic.uff.br">hsantos@ic.uff.br</a><br>Instituto de Computacao - Universidade Federal Fluminense