A region representing an interval on one or more axes of a Frame

The
Interval class implements a Region which represents upper and/or lower limits on one or more axes
of a Frame. For a point to be within the region represented by the Interval, the point must satisfy all
the restrictions placed on all the axes. The point is outside the region if it fails to satisfy any
one of the restrictions. Each axis may have either an upper limit, a lower limit, both or
neither. If both limits are supplied but are in reverse order (so that the lower limit is greater
than the upper limit), then the interval is an excluded interval, rather than an included
interval.

Note, The Interval class makes no allowances for cyclic nature of some coordinate systems (such as SkyFrame coordinates). A Box should usually be used in these cases since this requires the user to think about suitable upper and lower limits,

The Interval class inherits from the Region class.

The Interval class does not define any
new attributes beyond those which are applicable to all Regions.

The Interval
class does not define any new routines beyond those which are applicable to all Regions.

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