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<TITLE>Clp-1.7 Dual Simplex Algorithm</TITLE>
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<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Dear Clp forum,</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">I am using an IP solver that uses Clp-1.7.</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">My IP problems are</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">all</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">feasibility problems.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">I am trying to find all feasible solutions to an IP.</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">I am using the zero function as my objective (</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">i.e.</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">all of my objective function</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">'</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">s</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"> coefficients</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"> are equal to zero).</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"></FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">Then i</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">n the dual simplex algorithm</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"> all the calculations involving reduced costs are</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">unnecessary. Skipping these calculations will</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">undoubtedly speed up the dual simplex</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">calculations in solving an LP relaxation within an IP.</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"></FONT></SPAN><SPAN LANG="en-us"> </SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">I was wondering if there is a version of Clp whose dual simplex componen</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">t</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"> skips</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">calculations involving reduced costs</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"> when the objective function is the zero function</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">.</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"></FONT></SPAN><SPAN LANG="en-us"> </SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Dursun Bulutoglu</FONT></SPAN><SPAN LANG="en-us"></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"></SPAN></P>
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