GAMS — The Solver Manuals - Available Software

200 CPLEX 11
simdisplay (integer)
This option controls what Cplex reports (normally to the screen) during optimization.
information displayed increases as the setting value increases.
(default = 1)
0 No iteration messages are issued until the optimal solution is reported
The amount of
1 An iteration log message will be issued after each refactorization. Each entry will contain the iteration
count and scaled infeasibility or objective value.
2 An iteration log message will be issued after each iteration. The variables, slacks and artificials entering
and leaving the basis will also be reported.
singlim (integer)
The singularity limit setting restricts the number of times Cplex will attempt to repair the basis when
singularities are encountered. Once the limit is exceeded, Cplex replaces the current basis with the best
factorizable basis that has been found. Any non-negative integer value is valid.
(default = 10)
solnpool (string)
The solution pool enables you to generate and store multiple solutions to a MIP problem. The option expects
a GDX filename. This GDX file name contains the information about the different solutions generated by
Cplex. Inside your GAMS program you can process the GDX file and read the different solution point
files. Please check the GAMS/Cplex solver guide document and the example model solnpool.gms from the
GAMS model library.
solnpoolagap (real)
Sets an absolute tolerance on the objective bound for the solutions in the solution pool. Solutions that are
worse (either greater in the case of a minimization, or less in the case of a maximization) than the objective
of the incumbent solution according to this measure are not kept in the solution pool.
Values of the solution pool absolute gap and the solution pool relative gap solnpoolgap may differ: For
example, you may specify that solutions must be within 15 units by means of the solution pool absolute
gap and also within 1incumbent by means of the solution pool relative gap. A solution is accepted in the
pool only if it is valid for both the relative and the absolute gaps.
The solution pool absolute gap parameter can also be used as a stopping criterion for the populate procedure:
if populate cannot enumerate any more solutions that satisfy this objective quality, then it will stop. In
the presence of both an absolute and a relative solution pool gap parameter, populate will stop when the
smaller of the two is reached.
(default = 1e+075)
solnpoolcapacity (integer)
Limits the number of solutions kept in the solution pool. At most, solnpoolcapacity solutions will be stored
in the pool. Superfluous solutions are managed according to the replacement strategy set by the solution
pool replacement parameter solnpoolreplace.
The optimization (whether by MIP optimization or the populate procedure) will not stop if more than
solnpoolcapacity are generated. Instead, stopping criteria are regular node and time limits and populatelim,
solnpoolgap and solnpoolagap.
(default = 2100000000)
solnpoolgap (real)
Sets a relative tolerance on the objective bound for the solutions in the solution pool. Solutions that are
worse (either greater in the case of a minimization, or less in the case of a maximization) than the incumbent
solution by this measure are not kept in the solution pool.
Values of the solution pool absolute gap solnpoolagap and the solution pool relative gap may differ: For
example, you may specify that solutions must be within 15 units by means of the solution pool absolute gap
and within 1solution is accepted in the pool only if it is valid for both the relative and the absolute gaps.