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?Vars $:: ++Lo..Hi

EplexInstance: (?Vars $:: ++Lo..Hi)

Constrains list elements to lie between the given bounds.
Vars
Variable or number or a list of them
Lo..Hi
Lo, Hi are numbers or arithmetic expressions

Description

Constrain a variable (or all variables in a list) to take only values in a given range for the eplex instance EplexInstance. Any variables that are not already problem variables for EplexInstance will be added to the problem. The range information is passed to the external solver state associated with EplexInstance as floats. No type information are implied by the bounds.

In particular, if the bounds are given as integers, this information is not passed to the external solver. Unless eplex:integers/1 is invoked, any invocation of the eplex external solver (whether via eplex_solve/1, lp_solve/2, lp_demon_setup/5 or optimize/2) will only solve a continuous relaxation, even when problem variables have been declared as integers in other solvers (e.g. ic).

No propagation is done at the ECLiPSe level with the bounds. In particular, the variable is not instantiated even if the lower and upper bounds are identical. The bounds may be inconsistent with the bounds given for the variables in other EplexInstances or solvers (i.e. this will not result in immediate failure).

Exceptions

(5) type error
Lo..Hi is not in correct form
(5) type error
Lo and Hi are of different numeric types

See Also

integers / 1, reals / 1, :: / 2, suspend : #:: / 2, ic : #:: / 2, gfd : #:: / 2, fd : #:: / 2, suspend : $:: / 2, ic : $:: / 2