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<div class="moz-cite-prefix">I forgot to mention that it is a
minimization problem , so i do not know if there is any point in
limiting objective.<br>
<br>
Sorry for the double mail.<br>
<br>
On 10/8/2012 19:24, <a class="moz-txt-link-abbreviated" href="mailto:acw@ascent.com">acw@ascent.com</a> wrote:<br>
</div>
<blockquote
cite="mid:OF67100073.01543951-ON85257A56.00594F87-85257A56.005A33EA@ascent.com"
type="cite"><font face="sans-serif" size="2">No single constraint
is responsible for
an infeasibility. Consider a system with one variable, and two
constraints,
X >= 7 and X <= 4. This system is obviously infeasible,
but
which of the two constraints is at fault?</font>
<br>
<br>
<font face="sans-serif" size="2">In your case I suspect that the
problem
is unbounded rather than infeasible, because you have so few
constraints
and so many variables. Unless the problem has a very special
structure,
a problem with fewer constraints than variables is likely to be
unbounded.</font>
<br>
<br>
<font face="sans-serif" size="2">You can check this by adding a
constraint
that limits your objective to, say, 1e6. If the problem now
solves,
then unboundedness is almost certainly your difficulty.</font>
<br>
<br>
<br>
<table width="100%">
<tbody>
<tr valign="top">
<td><font color="#5f5f5f" face="sans-serif" size="1">From:</font>
</td>
<td><font face="sans-serif" size="1">Christos
<a class="moz-txt-link-rfc2396E" href="mailto:chtsolak@gmail.com"><chtsolak@gmail.com></a></font>
</td>
</tr>
<tr valign="top">
<td><font color="#5f5f5f" face="sans-serif" size="1">To:</font>
</td>
<td><font face="sans-serif" size="1"><a class="moz-txt-link-abbreviated" href="mailto:cbc@list.coin-or.org">cbc@list.coin-or.org</a></font>
</td>
</tr>
<tr valign="top">
<td><font color="#5f5f5f" face="sans-serif" size="1">Date:</font>
</td>
<td><font face="sans-serif" size="1">08/10/2012 09:32 AM</font>
</td>
</tr>
<tr valign="top">
<td><font color="#5f5f5f" face="sans-serif" size="1">Subject:</font>
</td>
<td><font face="sans-serif" size="1">[Cbc] Artificial
variables</font></td>
</tr>
</tbody>
</table>
<br>
<hr noshade="noshade">
<br>
<br>
<br>
<tt><font size="2">Hi, i have a model with around 10000 variable
and
1500 equations.<br>
<br>
But i get the messages on the photo when i run it:<br>
</font></tt><a moz-do-not-send="true"
href="http://imageshack.us/photo/my-images/39/dascd.png/"><tt><font
size="2">http://imageshack.us/photo/my-images/39/dascd.png/</font></tt></a><tt><font
size="2"><br>
<br>
Is there any way to use artificial variable or something else
in order
<br>
to find the problematic equation?<br>
<br>
Thank you in advance<br>
_______________________________________________<br>
Cbc mailing list<br>
<a class="moz-txt-link-abbreviated" href="mailto:Cbc@list.coin-or.org">Cbc@list.coin-or.org</a><br>
</font></tt><a moz-do-not-send="true"
href="http://list.coin-or.org/mailman/listinfo/cbc"><tt><font
size="2">http://list.coin-or.org/mailman/listinfo/cbc</font></tt></a><tt><font
size="2"><br>
</font></tt>
<br>
</blockquote>
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