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Add zero-cost-singleton for implied integers - #3455
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Great, thanks, @Opt-Mucca!
Codecov Report✅ All modified and coverable lines are covered by tests. Additional details and impacted files@@ Coverage Diff @@
## latest #3455 +/- ##
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+ Coverage 75.10% 75.12% +0.01%
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Files 460 460
Lines 112030 112155 +125
Branches 17757 17779 +22
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+ Hits 84144 84254 +110
- Misses 27604 27619 +15
Partials 282 282 ☔ View full report in Codecov by Harness. 🚀 New features to boost your workflow:
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Description
This change lets implied integers also be removed via
zeroCostSIngleton. That is, it removes the implied integer column from the single double-sided row that it features in, and then computes a value for it in postsolve. As it's integrality is only implied and it's bounds are always integer, I believe it's safe to remove this way. I found this while trying to figure out how SCIP made some reductions on an instance that we weren't doing.On my test set it results in a 1.4% performance improvement (am a bit amazed at this). The main instances affected are:
Edit: Misread my own tables.......
There's a few more affected instances, but they're only affected on specific seeds, so I assume they depend on some
submipor restart path to trigger these reductions.Checklist
latestbranch