<HTML><BODY style="word-wrap: break-word; -khtml-nbsp-mode: space; -khtml-line-break: after-white-space; ">I'm pretty sure there has been no work on quadratic constraints in CLP. Quadratic objectives are (partially) supported, so you could do some sort of a penalty approach for optimization with these constraints. I'm not familiar with CBC.<DIV><BR class="khtml-block-placeholder"></DIV><DIV>Matt</DIV><DIV><BR><DIV><DIV>On Sep 2, 2005, at 11:36 AM, Eugenio cONFORTI wrote:</DIV><BR class="Apple-interchange-newline"><BLOCKQUOTE type="cite"><DIV>Hello,</DIV> <DIV>I'm using CBC and CLP for my thesis and I need to do some quadratic constraint (but objective function is linear). for example:</DIV> <DIV> </DIV> <DIV>min <FONT size="3">x</FONT><FONT size="1">1</FONT>+2<FONT size="3">x</FONT><FONT size="1">2</FONT></DIV> <DIV>..........</DIV> <DIV><FONT size="3">x</FONT><FONT size="1">1 </FONT><FONT size="2">* </FONT><FONT size="3">x</FONT><FONT size="1">2></FONT><FONT size="3"> constant</FONT></DIV> <DIV><FONT size="3"></FONT> </DIV> <DIV>I didn't find anything like this.. Is it possible?</DIV> <DIV>Thank you,<BR></DIV> <DIV>Eugenio Conforti</DIV><DIV> <BR class="khtml-block-placeholder"></DIV><HR size="1"><FONT face="Arial" size="2"><A href="http://us.rd.yahoo.com/mail_it/taglines/*http://it.mail.yahoo.com"><B>Yahoo! Mail</B></A>: gratis 1GB per i messaggi, antispam, antivirus, POP3</FONT><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">_______________________________________________</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Coin-lpsolver mailing list</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><A href="mailto:Coin-lpsolver@list.coin-or.org">Coin-lpsolver@list.coin-or.org</A></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><A href="http://list.coin-or.org/mailman/listinfo/coin-lpsolver">http://list.coin-or.org/mailman/listinfo/coin-lpsolver</A></DIV> <BR class="Apple-interchange-newline"></BLOCKQUOTE></DIV><BR></DIV></BODY></HTML>