<html>
<head>
<meta content="text/html; charset=ISO-8859-1"
http-equiv="Content-Type">
</head>
<body bgcolor="#FFFFFF" text="#000000">
<div class="moz-cite-prefix">I noticed this recently when using
trunk. I took out assert in Osi/trunk and could see no harm in
it.<br>
<br>
It should not be a fatal error. I don't really have time to track
it down. It must be a minor bug in one of the CoinPresolve....
postsolvers.<br>
<br>
John Forrest<br>
On 01/04/13 16:28, Horand Gassmann wrote:<br>
</div>
<blockquote cite="mid:20130401122845.1634875nfeh4nyr0@wm2.dal.ca"
type="cite">Hi,
<br>
<br>
I am trying to solve a small aggregate planning model. (AMPL model
and data files attached.) The LP relaxation works fine, but when I
add an integrality constraint on the first set of variables
(number_workers), I get an assert error:
<br>
<br>
../../../../Osi/src/Osi/OsiPresolve.cpp:507: virtual void
OsiPresolve::postsolve(bool): Assertion `status !=
CoinWarmStartBasis::atUpperBound ||
originalModel_->getColUpper()[i] < infty' failed.
<br>
<br>
What causes the error is unclear to me. I do not provide a
starting basis, so I wouldn't expect the presolver to even go
there. Is this a bug? Does the presolver require finite upper
bounds? Any ideas?
<br>
<br>
Thanks
<br>
<br>
gus
<br>
-------------------------------------------------------
<br>
<br>
Horand I. Gassmann, Professor
<br>
<br>
Kenneth C. Rowe School of Business, Dalhousie University
<br>
6100 University Avenue, PO Box 15000
<br>
Halifax, Nova Scotia, Canada, B3H 4R2
<br>
ph. (902) 494-1844
<br>
fax (902) 494-1107
<br>
<br>
<a class="moz-txt-link-freetext" href="http://myweb.dal.ca/gassmann/">http://myweb.dal.ca/gassmann/</a>
<br>
<br>
<br>
----- End forwarded message -----
<br>
<br>
<br>
-------------------------------------------------------
<br>
<br>
Horand I. Gassmann, Professor
<br>
<br>
Kenneth C. Rowe School of Business, Dalhousie University
<br>
6100 University Avenue, PO Box 15000
<br>
Halifax, Nova Scotia, Canada, B3H 4R2
<br>
ph. (902) 494-1844
<br>
fax (902) 494-1107
<br>
<br>
<a class="moz-txt-link-freetext" href="http://myweb.dal.ca/gassmann/">http://myweb.dal.ca/gassmann/</a>
<br>
<br>
<fieldset class="mimeAttachmentHeader"></fieldset>
<br>
<pre wrap="">_______________________________________________
Osi mailing list
<a class="moz-txt-link-abbreviated" href="mailto:Osi@list.coin-or.org">Osi@list.coin-or.org</a>
<a class="moz-txt-link-freetext" href="http://list.coin-or.org/mailman/listinfo/osi">http://list.coin-or.org/mailman/listinfo/osi</a>
</pre>
</blockquote>
<br>
</body>
</html>