Originally posted by: Falcon_G
Hi everybody
I have got a MIP for which I generate cuts and add to the model. The cuts are added both in Lazy and also in the userCut callbacks.
It terminates as in the following. at a Gap of 10% when a feasible solution is already known, switches to a gap of -90.20% and then 0 and terminates.
And the solution is incorrect. I wonder why this negative gap appears here.
Any idea?
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* 0+ 0 3455.1781 3108.2119 4144 10.04%
Repair heuristic found nothing.
Repeating presolve.
Tried aggregator 2 times.
MIP Presolve eliminated 3476 rows and 75 columns.
MIP Presolve modified 327 coefficients.
Aggregator did 1 substitutions.
Reduced MIP has 835 rows, 198 columns, and 4105 nonzeros.
Reduced MIP has 114 binaries, 0 generals, 0 SOSs, and 0 indicators.
Presolve time = 0.03 sec. (8.12 ticks)
Probing time = 0.00 sec. (1.42 ticks)
Tried aggregator 1 time.
Reduced MIP has 835 rows, 198 columns, and 4105 nonzeros.
Reduced MIP has 114 binaries, 0 generals, 0 SOSs, and 0 indicators.
Presolve time = 0.02 sec. (1.57 ticks)
Represolve time = 0.08 sec. (19.32 ticks)
Probing time = 0.02 sec. (1.42 ticks)
Probing added 267 nonzeros.
Clique table members: 122.
MIP emphasis: best bound.
MIP search method: traditional branch-and-cut.
Parallel mode: none, using 1 thread.
Root relaxation solution time = 0.03 sec. (18.08 ticks)
Nodes Cuts/
Node Left Objective IInf Best Integer Best Bound ItCnt Gap Variable B NodeID Parent Depth
* 0+ 0 1634.2075 3108.2119 4329 -90.20%
0 0 cutoff 1634.2075 4329 0.00%
Flow cuts applied: 1
User cuts applied: 779
Root node processing (before b&c):
Real time = 21.39 sec. (8364.92 ticks)
Sequential b&c:
Real time = 0.00 sec. (0.00 ticks)
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Total (root+branch&cut) = 21.39 sec. (8364.92 ticks)
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