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Cut Generator Library
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CglFlowCover cut chops off optimal solution to egout #26

Closed svigerske closed 5 years ago

svigerske commented 5 years ago

Issue created by migration from Trac.

Original creator: @rlougee

Original creation time: 2008-06-13 14:45:32

Assignee: somebody

Version: stable 0.5

John Forrest sent me an example where a CglFlowCover cut chops off the optimal solution to egout. John turned off lifting in CglFlowCover cuts in stable and trunk.

svigerske commented 5 years ago

Comment by @rlougee created at 2008-06-13 14:46:10

Changing assignee from somebody to @rlougee.

svigerske commented 5 years ago

Comment by @rlougee created at 2008-06-13 14:46:22

Changing status from new to assigned.

svigerske commented 5 years ago

Comment by @rlougee created at 2008-06-13 15:40:22

The bug was in the lifted coefficient for j in C-. The reference paper defines "y" binary and "x" continuous. The code uses the reverse ("x" binary, "y" continuous). The lifted coefficient value was being calculated correctly but it was getting assigned incorrectly. The fix was to change a "yCoef" to "xCoeff." (I wonder if for the sake of maintainability if we shouldn't change the code to conform to the definitions in the paper.)

svigerske commented 5 years ago

Comment by @rlougee created at 2008-06-13 15:40:22

Resolution: fixed