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<p class="MsoNormal"><span lang="EN-US">Hi SCIP Team,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I try to solve a MIP with SCIP within Google OR-Tools. It is set up with 8 threads and a time limit of 90min. I do not know if the following problem is due to Google OR or SCIP.
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">In the console output, I see a progress table with dualbounds and primalbounds as below.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">The final primal bound reported at termination (4.03e+04) is much worse than the last values shown in the table (e.g. 2.50e+04). The same for dual.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">This looks like SCIP found better solutions during the run, but they are not kept until the end.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Could you please help me to understand what exactly is shown in the progress table and if there is a good reason to see better values there than in the final solution?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Thank you very much!<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Best regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Ines<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">time | mem | dualbound | primalbound | gap
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">$ 506s|1407M| 6.131990e+03 | 3.899735e+09 | Large
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">…<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">$3186s|2181M| 6.582145e+03 | 4.037315e+04 | 513.37%
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">…<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">$5165s|3298M| 6.956456e+03 | 2.509565e+04 | 260.75%
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">concurrent solver 'scip-2' stopped with status time limit reached
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">concurrent solver 'scip-5' stopped with status time limit reached
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">concurrent solver 'scip-3' stopped with status time limit reached
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">concurrent solver 'scip-8' stopped with status time limit reached
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">concurrent solver 'scip-6' stopped with status time limit reached
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">concurrent solver 'scip-7' stopped with status time limit reached
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">5402s|3106M| 6.967374e+03 | 2.509565e+04 | 260.19%
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">concurrent solver 'scip-1' stopped with status time limit reached
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">concurrent solver 'scip-4' stopped with status time limit reached
<o:p></o:p></span></p>
<p class="MsoNormal"><b><span lang="EN-US">5402s|3106M| 6.967374e+03 | 2.509565e+04 | 260.19%
<o:p></o:p></span></b></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">SCIP Status : solving was interrupted [time limit reached]
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Solving Time (sec) : 5402.00 <o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Solving Nodes : 3941 <o:p></o:p></span></p>
<p class="MsoNormal"><b><span lang="EN-US">Primal Bound : +4.03731513404846e+04 (44 solutions)
<o:p></o:p></span></b></p>
<p class="MsoNormal"><b><span lang="EN-US">Dual Bound : +6.24112774276733e+03 <o:p>
</o:p></span></b></p>
<p class="MsoNormal">Gap : 546.89 % <o:p></o:p></p>
<p class="MsoNormal" style="text-align:justify;text-autospace:none"><span style="font-size:8.0pt;color:#002060;mso-fareast-language:DE"><o:p> </o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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