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<p class=MsoNormal><span lang=DE>Hello,<o:p></o:p></span></p>
<p class=MsoNormal><span lang=DE><o:p> </o:p></span></p>
<p class=MsoNormal>in my program I do an initialSolve(), check the solution
status and if the solution is optimal I enable the simplex interface with
enableSimplexInterface(true).<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Occasionally, the solver seems to change some internal
solution status that I do not quite understand: With the latest trunk, line 572
of ClpSimplex.cpp calls nonLinearCost_->checkInfeasibilities(). If I
understand correctly, this method checks each variables' status including slack
variables. In my case, calling enableSimplexInterface(true) causes a status
change for one variable which leads to a change in the costs for this variable.
By consequence, this changes the value of my objective function.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Should a call to enableSimplexInterface be followed by a
call to resolve() to correct the solution?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Thanks in advance,<o:p></o:p></p>
<p class=MsoNormal>Sebastian<o:p></o:p></p>
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<!--[object_id=#0342cca8cd3ef743bdaeaa37dbcc7c82#]--><P style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma,Verdana,Arial">--<BR>Sebastian Theophil (<A href="mailto:stheophil@think-cell.com">stheophil@think-cell.com</A>)<BR>Software Engineer </P><!--[object_id=#think-cell.com#]--><TABLE style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma,Verdana,Arial" cellSpacing=0>
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<TD style="PADDING-RIGHT: 10pt">think-cell Software GmbH</TD>
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