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<p>Sebastian,<br>
<br>
I think I had fixed those errors in my copy of trunk. Owing to lack of bandwidth I had not checked in. Do new changes help?<br>
<br>
John Forrest<br>
<br>
<img width="16" height="16" src="cid:1__=0ABBFCCEDFC2A1978f9e8a93df938@us.ibm.com" border="0" alt="Inactive hide details for "Sebastian Theophil" ---10/28/2009 07:12:04 AM---Hi, I'm trying to avoid the accumulation of rounding"><font color="#424282">"Sebastian Theophil" ---10/28/2009 07:12:04 AM---Hi, I'm trying to avoid the accumulation of rounding errors by repeatedly</font><br>
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<font size="2" color="#5F5F5F">From:</font></td><td width="100%"><img width="1" height="1" src="cid:2__=0ABBFCCEDFC2A1978f9e8a93df938@us.ibm.com" border="0" alt=""><br>
<font size="2">"Sebastian Theophil" <stheophil@think-cell.com></font></td></tr>
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<font size="2" color="#5F5F5F">To:</font></td><td width="100%"><img width="1" height="1" src="cid:2__=0ABBFCCEDFC2A1978f9e8a93df938@us.ibm.com" border="0" alt=""><br>
<font size="2"><clp@list.coin-or.org></font></td></tr>
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<font size="2" color="#5F5F5F">Date:</font></td><td width="100%"><img width="1" height="1" src="cid:2__=0ABBFCCEDFC2A1978f9e8a93df938@us.ibm.com" border="0" alt=""><br>
<font size="2">10/28/2009 07:12 AM</font></td></tr>
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<font size="2" color="#5F5F5F">Subject:</font></td><td width="100%"><img width="1" height="1" src="cid:2__=0ABBFCCEDFC2A1978f9e8a93df938@us.ibm.com" border="0" alt=""><br>
<font size="2">[Clp] Crash in ClpDualRowSteepest copy ctor</font></td></tr>
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<font size="2" color="#5F5F5F">Sent by:</font></td><td width="100%"><img width="1" height="1" src="cid:2__=0ABBFCCEDFC2A1978f9e8a93df938@us.ibm.com" border="0" alt=""><br>
<font size="2">clp-bounces@list.coin-or.org</font></td></tr>
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<tt>Hi,<br>
<br>
<br>
I'm trying to avoid the accumulation of rounding errors by repeatedly<br>
solving the same solver object. I also want to avoid having to<br>
reassemble the same constraint system over and over again. So I make a<br>
copy of a previous solver, change constraints, resolve and throw the<br>
copy away again. This seems to trigger some unexpected test cases:<br>
<br>
- OsiClpSolverInterface copy ctor makes a copy of the ClpSimplex*<br>
modelPtr_ <br>
- ClpSimplex copy ctor calls ClpSimplex::gutsOfCopy <br>
- which makes a copy of dualRowPivot_ and primalColumnPivot_<br>
<br>
Both contain a copy to their parent ClpSimplex* that has previously been<br>
set by ClpDualRowPivot::saveWeights<br>
<br>
The ClpDualRowSteepest and ClpDualRowPivot copy ctors simply copy the<br>
ClpSimplex* which may be okay in many circumstances but it is certainly<br>
wrong when called from the ClpSimplex copy ctor. <br>
<br>
Is it safe to call <br>
<br>
dualRowPivot_ = rhs.dualRowPivot_->clone(false);<br>
primalColumnPivot_ = rhs.primalColumnPivot_->clone(false);<br>
<br>
<br>
in ClpSimplex::gutsOfCopy and thus prevent any data from being copied? <br>
<br>
Thanks<br>
Sebastian<br>
<br>
--<br>
Sebastian Theophil . stheophil@think-cell.com<br>
Software Engineer<br>
<br>
think-cell Software GmbH . Invalidenstr. 34 . 10115 Berlin, Germany <br>
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