The class ContinuousConstraint stores constraints for a variable.
Constraints are given either as a continuous range (any value between a min and a max boundary is admissible)
or a discrete set of values (any value belonging to the set is admissible).
Constraint objects are typically created by calls to constraint
and contain the following slots:
type:A character string, one of 'continuous' or 'discrete'.
range:A numeric vector with two values giving the min/max of the continuous range.
minimalDelay:A numeric value giving the minimal timestep between two sampling times.