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# lp_get(++ParamName, ?Value)

Obtain the value of a global parameter.

ParamName
  Atom
Value
  Variable, integer, float or atom

## Description

Eplex have a number of global (i.e. not specific to a particular problem) parameters. These can be queried using this predicate.

`optimizer`
  Returns the name of the external solver, currently 'cplex', 'xpress' or 'osi'.
`optimizer_version`
  Returns an integer derived from the version of the external solver (for osi, the version is the actual solvers used)
`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. The value is 1 if the default is to have presolve on, and 0 if off. Note that this is a change from previous versions of eplex, where this parameter is directly connected to the external solver's own presolve parameter. However, the solver may have more than one parameter for presolve settings, and these may take on more values than 0 and 1. In such cases, eplex will set the parameters(s) to some default value(s) corresponding to presolve being off and on. These parameters can be accessed directly using the optimizer_param option if required.
`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.
`standalone`
  Value is `yes', as this is the stand-alone version of Eplex. as the external solver is used for keeping the bounds. This option allows programmer to write code that needs to distinguish between the stand-alone and the non-stand-alone versions of Eplex.
`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