<br><font size=2 face="sans-serif">I have modified code to allow for initial
basis. Does no harm.</font>
<br>
<br><font size=2 face="sans-serif">Tell me if it helps - if not send a
driver and I will get it to work.</font>
<br>
<br><font size=2 face="sans-serif">John Forrest</font>
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<td width=40%><font size=1 face="sans-serif"><b>js@jeannot.org</b> </font>
<br><font size=1 face="sans-serif">Sent by: coin-lpsolver-admin@www-124.southbury.usf.ibm.com</font>
<p><font size=1 face="sans-serif">08/26/2004 04:36 AM</font>
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<div align=right><font size=1 face="sans-serif">To</font></div>
<td valign=top><font size=1 face="sans-serif">coin-lpsolver@www-124.southbury.usf.ibm.com</font>
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<div align=right><font size=1 face="sans-serif">cc</font></div>
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<div align=right><font size=1 face="sans-serif">Subject</font></div>
<td valign=top><font size=1 face="sans-serif">[Coin-lpsolver] Problem using
setBasisStatus() as a hint for Clp</font></table>
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<br><font size=2><tt>Hi !<br>
<br>
I often get the following error when using the Osi setBasisStatus() function:<br>
Clp0007I Singular factorization of basis - status -1<br>
Assertion failed: internalFactorize(1)==0, file ClpSimplex.cpp, line 5411<br>
<br>
Looking at the code, it seems that ClpSimplex::setBasisStatus() calls<br>
ClpSimplex::statusOfProblem(), which then assert internalFactorize(1)==0.<br>
<br>
I use setBasisStatus() to provide a starting point to Clp when doing<br>
initialSolve(), but the basis status I provide may not lead to a correct<br>
factorization (it may not be a basis).<br>
<br>
Is there a way to provide an approximate basis status as a hint to Clp
?<br>
<br>
Thank you very much in advance,<br>
<br>
Regards,<br>
<br>
js<br>
<br>
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