
lp_get(+Handle, ++ParamName, -Value)

   Retrieve information about solver state and results for solver state Handle.

Arguments
   Handle              Handle to an exisiting solver state
   ParamName           Name of parameter (atom)
   Value               Returned value for ParamName

Type
   library(eplex)

Description

   Retrieve information about solver state and results for the solver state
   represented by Handle. ParamName is the same as that
   for eplex_get/2, which retrieves the same information via the EplexInstance.
   It can  be one of:



     vars
     Returns a term ''(X1,...,Xn) whose arity is the number of
         variables involved in the solver's constraint set, and whose
         arguments are these variables.


     ints
     Returns a list [Xi1,...,Xik] which is the subset of the problem
         variables that the solver considers to be integers.


     constraints_norm
     Returns a list of the problem constraints in normalised form.
         They may be simplified with respect to the original set that 
         was passed to lp_setup/4.


     constraints
     Returns a list of the problem constraints in denormalised (readable)
         form.  They may be simplified with respect to the original set
         that was passed to lp_setup/4.


     objective
     Returns a term min(E) or max(E), representing objective function
         and optimisation direction. E is a linear expression.


     method
     Returns the method (default, primal, dual, net_primal, net_dual, 
         barrier, barrier_primal, barrier_dual) that is used to solve 
         the problem.
	 In case of MIP solving, this is the start algorithm (the one that
	 is used to solve the initial relaxation).


     status
     Status that was returned by the most recent invocation of the 
         external solver.


     cost
     Cost of the current solution.
         Fails if no solution has been computed yet.


     typed_solution
     Returns a term ''(X1,...,Xn) whose arguments are the properly
         typed (integer or float) solution values for the corresponding
         problem variables (vars).  The floating point solutions
         are the same as returned by solution, the integers are
         obtained by rounding the corresponding floating-point solution to
         the nearest integer.  To instantiate the problem variables to
         their solutions, unify this term with the corresponding term
         containing the variables:


    instantiate_solution(Handle) :-
        lp_get(Handle, vars, Vars),
        lp_get(Handle, typed_solution, Values),
        Vars = Values.



    slack

    Returns a list of floating-point values representing the constraint
        slacks. The order corresponds to the list order in
        constraints.  Fails if no solution has been computed yet.


    dual_solution
    Returns a list of floating-point values representing the dual
        solutions.  The order corresponds to the list order in
        constraints.  Fails if no solution has been computed yet.


    demon_tolerance
    Returns a comma-separated pair (RealTol,IntTol) of
        floating-point values which specify how far outside a variable's
        range an lp-solution can fall before lp_demon_setup/6
        re-triggers. The tolerances differ for real (default 0.00001) and
        integer (default 0.5) variables.


    simplex_iterations
    Returns the external solver's count of simplex iterations.


    node_count
    Returns the external MIP solver's node count.


    statistics
    Returns a list of counter values [Successes, Failures,
        Aborts], indicating how often lp_solve/2 was invoked on the
        Handle, and how many invocations succeeded, failed and aborted
        respectively.


    pool
    Returns the name of the eplex instance (if any) associated with 
        the solver state. Fails otherwise. Only useful if called with 
        lp_get/3.

    handle
    Returns the solver state handle (if any) associated with the eplex 
        instance. Fails otherwise. Only useful if called with eplex_get/2.


Note that reduced_cost, slack, dual_solution can only be retrieved
when previously requested in the option list of lp_setup/4 or with lp_set/3.


See Also
   lp_setup / 4, lp_set / 3, eplex_get / 2
