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<div class="" style="word-wrap:break-word">Hi everyone,
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<div class="">this is my first post, so please understand that my knowledge of SCIP is low!</div>
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<div class="">I have been solving some large binary linear programming problems with no objective function. I solve .LP files using a terminal to issue the commands on my Mac. The .LP files are automatically generated, with e.g. the attached format.</div>
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<div class="">The only commands I issue are</div>
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<div class="">SCIP> read test.lp</div>
<div class="">SCIP> optimize test.lp</div>
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<div class="">The problem is that for very large problems (e.g. 28456 variables) the solver seems to be running forever (> 2 days)! I tried the same problem in Gurobi and it gave me the correct solution in 15 minutes. (I’m wanting to use SCIP because it has
some easy options for giving me all feasible solutions, while Gurobi does not).</div>
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<div class="">I also tried the problem in CPLEX, but it has some limitations on the length of the variable names (Error 1464) so I’m a little stuck if I want multiple solutions for large problems.</div>
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<div class="">Any advice would be appreciated.</div>
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<div class="">Marcus.</div>
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<div class="">PS I only know how to problems in the .LP format!</div>
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<div class="" style="font-size:12px; orphans:2; widows:2; margin:0px"><font face="Helvetica" class="">________________________________</font></div>
<div class="" style="font-size:12px; orphans:2; widows:2; margin:0px"><font face="Helvetica" class="">Marcus R Garvie</font></div>
<div class="" style="font-size:12px; orphans:2; widows:2; margin:0px"><font face="Helvetica" class="">Associate Professor</font></div>
<div class="" style="font-size:12px; orphans:2; widows:2; margin:0px"><font face="Helvetica" class="">Rm 552 MacNaughton Bldg</font></div>
<div class="" style="font-size:12px; orphans:2; widows:2; margin:0px"><font face="Helvetica" class="">Dept. of Math & Stats</font></div>
<div class="" style="font-size:12px; orphans:2; widows:2; margin:0px"><font face="Helvetica" class="">University of Guelph</font></div>
<div class="" style="font-size:12px; orphans:2; widows:2; margin:0px"><font face="Helvetica" class="">Guelph, ON Canada N1G 2W1</font></div>
<div class="" style="font-size:12px; orphans:2; widows:2; margin:0px"><font face="Helvetica" class="">Tel. 519-824-4120 ext 53409</font></div>
<div class="" style="font-size:12px; orphans:2; widows:2; margin:0px"><font face="Helvetica" class="">Email. <a href="mailto:mgarvie@uoguelph.ca" class=""><font color="#0020e3" class="" style="color:rgb(0,32,227)"><u class="">mgarvie@uoguelph.ca</u></font></a></font></div>
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