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coin-or / Cgl

Cut Generator Library
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error in definition of L-- in CglFlowCover.cpp #25

Closed svigerske closed 5 years ago

svigerske commented 5 years ago

Issue created by migration from Trac.

Original creator: @rlougee

Original creation time: 2008-02-13 16:59:36

Assignee: @rlougee

In CglFlowCover.cpp, the test on line 776 should be removed and the line on 777 should be uncommented.

776 if ( y[i] >= lambda * x[i] ) { // L- 777 // if ( up[i] > lambda) { // L-

For miplib problem egout.mps with the lifting enabled, the test on line 777 leads to a variable at zero in the set L- being treated as in the set L--...producing a bad cut which chops off the optimal solution.

svigerske commented 5 years ago

Comment by @rlougee created at 2008-02-13 19:29:55

Resolution: fixed