GAMS — The Solver Manuals - Available Software

AlphaECP 11
NLP solver for subproblems
NLPsolver=CONOPT
Call NLP solver at iteration (next:limitx2)
callNLPiter=500
Call NLP solver if same integer solution
nlplim_sameint=5
Call NLP solver if violation below epsilon_nlp
nlplim_epsilon=20
Tolerance when nlplim_epsilon count is increased epsilon_nlp=0.5
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Itera Stepcode, Number Del Alpha OPT Movement Viol Maximum MIPobjval
tion Problems of Cuts Cuts Upd. CR Norm Cons Violation
0 H 0 0 0 1 0 4 1.8E+003 NA
1 H 1 0 0 1 1.2E+004 4 1.8E+003 4943.75
2 H 2 0 0 1 1E+004 4 1.8E+003 4943.75
3 H 3 0 0 1 2.9E+003 4 1.8E+003 4943.75
4 H 4 0 0 1 3.6E+003 4 9E+002 4943.75
5 NLP call (nlplim_sameint) FOUND : 8566.12
5 L 5 0 5 1 1.3E+003 0 1.1E-013 8566.119
5 FOUND SOLUTION: 8566.12
6 H 5 0 0 1 1.7E+003 4 9.5E+002 4843.75
...
163 GM 132 0 0 0.1 0 0 0.00087 8566.115
164 GM 132 0 0 0 0 0 0.00087 8566.115
165 GM 132 0 0 0 0 0 0.00087 8566.115
Best solution: 8566.12
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Exit status
: Returning NLP solver result
Final solution
: NLP
Objective value : 8566.1189613135684
Max constraint (2) : 1.3904377738072071e-007
Alternative solution : MIP
Alt. objective value : 8566.1150929773648
Max constraint (4) : 0.00086733129398908204
Time used (seconds) : 14.38
Time limit (seconds) : 1000
Iterations used : 165
Iteration limit : 0
Number of cuts : 132
Function evaluations : 680
Gradient evaluations : 148
ECP time usage : 1.3 %
NLP time usage : 31.2 %
MIP time usage : 67.5 %
Optimal/total MIPs : 2/165
NLP solver calls : 27
Alphamax bound violations : 0
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In every iteration, information of the MIP problem and the modifications to the MIP problem, is given in 10
columns. Here is a description of the different columns:
Iteration: Iteration identifier.
Stepcode, Problems Letter for what actions where taken in this iteration and how the MIP problem was modified
before the next MIP solver call.