<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<style type="text/css" style="display:none;"> P {margin-top:0;margin-bottom:0;} </style>
</head>
<body dir="ltr">
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof">
Hi all,</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof">
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof">
I have a problem which after presolving contains the following vars and conss (among a bunch of other stuff):</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof">
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof ContentPasted0 ContentPasted1">
OBJECTIVE
<div class="ContentPasted0"> Sense : minimize</div>
<div class="ContentPasted0"> Offset : -62.7528704623564</div>
<div class="ContentPasted0">VARIABLES</div>
<div class="ContentPasted0 elementToProof">...<br>
</div>
<div class="ContentPasted0"> [binary] <t_pa#1>: obj=8.51719319141624, global bounds=[-0,1], local bounds=[-0,1]</div>
<div class="ContentPasted0 elementToProof"> ....</div>
<div class="ContentPasted0"> [binary] <t_v#0>: obj=33.6097102878493, global bounds=[-0,1], local bounds=[-0,1]</div>
<div class="ContentPasted0 elementToProof"> ...</div>
<div class="ContentPasted0 elementToProof">CONSTRAINTS</div>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof ContentPasted0 ContentPasted1">
...</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof ContentPasted0 ContentPasted1">
[logicor] <cluster_or>: logicor(<t_v#0>[B],<~t_pa#1>[B]);<br class="ContentPasted1">
...<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof">
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof">
The variable t_v#0 appears only in the above logicor constraint. So clearly in any optimal solution t_pa#1 = t_v#0. So I was expecting t_v#0 and its constraint to be
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof">
removed and the objective coefficient of t_pa#1 to be increased by 33.609. But this isn't happening. Is there perhaps some presolving parameter I could set to make this happen?</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof">
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof">
It's not a big deal for me to do this presolving "manually" as I construct the problem instance but it would be nicer if it "just happened".</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof">
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof">
James<br>
</div>
<div class="elementToProof">
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div id="Signature">
<div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
James Cussens</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Room MVB 3.26<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Dept of Computer Science, University of Bristol</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Phone: +44 (0)117 455 8723<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<a href="https://jcussens.github.io/">https://jcussens.github.io/</a></div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<span style="font-size:11.5pt">Funded PhDs available in Bristol in the following areas: <a href="http://www.bristol.ac.uk/cdt/compass/" target="_blank" rel="noopener noreferrer"><span>Data Science</span></a>, <a href="http://www.bristol.ac.uk/cdt/interactive-ai/" target="_blank" rel="noopener noreferrer"><span>Interactive
AI</span></a>, <a href="http://www.bristol.ac.uk/cdt/cyber-security/" target="_blank" rel="noopener noreferrer"><span>Cyber Security</span></a> or <a href="http://www.bristol.ac.uk/cdt/digital-health/" target="_blank" rel="noopener noreferrer"><span>Digital
Health</span></a>. </span><br>
</div>
</div>
</div>
</div>
</body>
</html>