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lp_get(++ParamName, ?Value)
Obtain the value of a global parameter.
- ParamName
- Atom or structure
- Value
- Variable, integer, float or atom
Description
Eplex has a number of global (i.e. not specific to a
particular problem) parameters. These can be queried using this
predicate.
- has_indicator_constraints
- Returns 'yes' if the solver supports =≥/2 indicator constraints,
else 'no'.
- has_miqp
- Returns 'yes' if the solver supports mixed integer problems
with quadratic objectives, else 'no'.
- has_qp
- Returns 'yes' if the solver supports quadratic objectives,
else 'no'.
- has_sos
- Returns 'yes' if the solver supports special ordered sets (SOS),
i.e. the sos1/1 and sos2/1 constraints.
else 'no'.
- optimizer
- Returns the name of the external solver, currently
'cplex', 'glpk', 'gurobi', 'osi' or 'xpress'.
- optimizer_version
- Returns an integer derived from the version of the
external solver (for osi, the version is the actual solvers
used, including any significant third-party packages such as
sparse matrix ordering packages required by the barrier solver)
- presolve
- Returns the default presolve setting for solver setup, i.e. the
presolve setting that a solver state would be given if it was not
directly specified during setup. A value of 0 disables presolving.
A value of 1 either enables presolving (for external solvers that
have only global parameters), or uses the default optimizer_param
settings (for external solvers with per-problem parameters).
- timeout
- Returns the default time-out setting that a solver state would
be given if it was not directly specified during setup. Value is
0 if there is no time-out.
- optimizer_param(Param)
- Get the Value of the external solver's parameter Param.
The exact behaviour and available parameters are dependent on the
external solver: if the external solver has only problem specific
parameters (e.g. XPRESS-MP 13 and later), this gets the default
setting that would be used for new problems; if the external solver
has global parameters, this gets the global value for the parameter.
If Param is not a valid parameter for the solver, an out of range
error is raised. See lp_get/3 for more details on the parameters.
Modes and Determinism
- lp_get(++, -)
- lp_get(++, +)
See Also
lp_set / 2