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<body class='hmmessage'><div dir='ltr'><font face="Calibri,sans-serif" size="3" style="font-size:12pt;" color="#000000">Hi all,</font><div><br></div><div><div>I have implemented branch-and-price using Scip,</div><div>and launch it to solve short examples before attacking big ones.</div><div>I noticed that when I give an optimal solution as initial columns </div><div>for the master or also during the solving, the pricing process generates unused columns, which are in final all zero (because they not participate in optimal solution).</div><div>So, I wonder why the pricing generates columns while an already optimal solution was given, is it due to duals given by Scip or ... ?</div></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">Thanks for any help</font></div><div><font face="Calibri,sans-serif" size="3" style="font-size:12pt;" color="#000000">With regards</font></div><div><font face="Calibri,sans-serif" size="3" style="font-size:12pt;" color="#000000">---</font></div><div><font face="Calibri,sans-serif" size="3" style="font-size:12pt;" color="#000000">A. Ouali</font></div></div> </div></body>
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