<html>
<head>
<style><!--
.hmmessage P
{
margin:0px;
padding:0px
}
body.hmmessage
{
font-size: 12pt;
font-family:Calibri
}
--></style></head>
<body class='hmmessage'><div dir='ltr'><font face="Calibri,sans-serif" size="3" style="font-size:12pt;" color="#000000">Hi Diego,</font><div><font face="Calibri,sans-serif" size="3" style="font-size:12pt;" color="#000000"><br></font></div><div><div>So, the problem is in my implementation, if it works for you, it must works for me...</div><div>perhaps i have missed something, i will check again upon the example given by Thomas,</div><div><br></div><div>Anyway thanks for help</div></div><div><font face="Calibri,sans-serif" size="3" style="font-size:12pt;" color="#000000"><br></font></div><div><font face="Calibri,sans-serif" size="3" style="font-size:12pt;" color="#000000">A. Ouali <br id="FontBreak"></font><br><br><div><hr id="stopSpelling">Date: Fri, 17 Oct 2014 08:28:03 +0200<br>From: dponce@us.es<br>To: oualiaek@hotmail.fr<br>CC: rodolfo.carvajal@gmail.com; scip@zib.de<br>Subject: Re: [Scip] Getting duals values of best solution<br><br>
Hi Abdelkader,<BR>
you wrote that you have used the transformed ones, but for me it works in my pricing by means of functions SCIPgetTransformedCons() and SCIPgetDualsolLinear(). They are used in VRP example.<BR>
Sorry if this is not new information for you.<BR>
Diego.<BR>
<BR>
<div> </div>
El 17/10/2014 01:26, Abdelkader Ouali escribió:<BR>
<blockquote style="padding-left:5px;border-left:#1010ff 2px solid;">
<div dir="ltr"><span style="font-size:medium;color:#000000;font-family:Calibri, sans-serif;"><br id="ecxFontBreak"></span>Hi Rodolfo,
<div> </div>
<div>Thank's for reply.</div>
<div> </div>
<div>
<div>But when applying pricing, we use dual values to get the reduced cost,</div>
<div>in my case, i don't get the correct values of dual variables.</div>
<div>The earlier example is one iteration of column generation, at these step</div>
<div>scip found the optimal solution of the master problem, so no need to generate new columns,</div>
<div>the problem is that the value of dual variable are all zero, which is not correct, and scip</div>
<div>continue to generate new columns.</div>
</div>
<div> </div>
<div>So how we can get dual variables in pricing if scip don't provide dual information ? </div>
<div> </div>
<div>Best regards</div>
<div> </div>
<div>A. Ouali </div>
<div> </div>
<div> <br><br>
<div><hr id="ecxstopSpelling">Date: Thu, 16 Oct 2014 18:17:20 -0300<br>Subject: Re: [Scip] Getting duals values of best solution<br>From: rodolfo.carvajal@gmail.com<br>To: oualiaek@hotmail.fr<br><br>
<p dir="ltr">Hi Abdelkader,<br> If you solve your MIP as a SCIP problem, you don't get dual information (see the SCIP FAQ <a href="http://scip.zib.de/#faq" target="_blank">http://scip.zib.de/#faq</a>).<br> You can use the LP interface (lpi/lpi.h) to interact with the LP solver and get the duals.</p>
<p dir="ltr">Hope this helps,<br> Rodolfo</p>
<div class="ecxgmail_quote">On Oct 16, 2014 5:49 PM, "Abdelkader Ouali" <<a href="mailto:oualiaek@hotmail.fr">oualiaek@hotmail.fr</a>> wrote:<br>
<blockquote class="ecxgmail_quote" style="border-left:1px #ccc solid;padding-left:1ex;">
<div>
<div dir="ltr">Dear scip users,
<div><br>
<div>
<div>I have a short example of ILP, and i want to know how to get dual values of optimal solution,</div>
<div>when i use cplex, it give me the correct value of dual variables,</div>
<div>but when using scip the dual values is all zero, knowing that i set the pointers of constraint to the transformed</div>
<div>ones, in attachment you will find source code containing the example and how i do to get the dual values.</div>
<div> </div>
<div>I want to know what is wrong in this code ?</div>
</div>
<div> </div>
<div>Best regards</div>
<div> </div>
<div>A. Ouali </div>
</div>
</div>
</div>
<br>_______________________________________________<br> Scip mailing list<br><a href="mailto:Scip@zib.de">Scip@zib.de</a><br><a href="http://listserv.zib.de/mailman/listinfo/scip" target="_blank">http://listserv.zib.de/mailman/listinfo/scip</a><br><br></blockquote>
</div>
</div>
</div>
</div>
<br>
<pre>_______________________________________________
Scip mailing list
<a href="mailto:Scip@zib.de">Scip@zib.de</a>
<a href="http://listserv.zib.de/mailman/listinfo/scip" target="_blank">http://listserv.zib.de/mailman/listinfo/scip</a>
</pre>
</blockquote></div></div> </div></body>
</html>