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lp_get_license_challenge(-Challenge)

Get parameter for computing license key (some external solvers only)
Challenge
Variable

Description

This is only needed for certain OEM versions of external solvers!

The eplex-library interfaces to an external simplex/MIP solver which might require a license to run (e.g. CPLEX, XPRESS-MP). Certain versions of these external solvers use a challenge- response licensing system. Only in such cases is this predicate needed. lp_get_license_challenge/1 returns a value which is used to compute a license key. This key is then passed into lp_get_license/2. For the details of this procedure you will need to consult the documentation of the solver vendor.

If you have a development license of CPLEX or XPRESS-MP, this predicate does not need to be called. If called anyway, it fails.

Fail Conditions

Fails if the solver doesn't use a challenge-response licensing system

Examples

     ?- ( lp_get_license_challenge(Challenge) ->
	    magic_formula(Challenge, Response),
	    lp_get_license(RuntimeLicenseString, Response)
	;
	    lp_get_license(DevelopmentLicensePath, 0)
	).

See Also

lp_get_license / 2