[Closed] Animation Range

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From the docs (after searching for animationrange):

The following 3ds Max system global variables are applicable to the Time Configuration dialog:
animationRange 
A System Global variable which lets you get and set an Interval value that defines the start and end frames of the Active Time Segment.
It contains the values set in the Time Configuration dialog>Animation>Start Time and End Time and displayed by the Active Time Segment option in the Time Output group of controls in the Render Scene Dialog.
The start and end values of the animationRange interval can be read individually using animationRange.start and animationRange.end .
They cannot be set separately though- the complete interval has to be assigned to the animationRange variable.
EXAMPLES:
animationRange --Get the current animation range
(interval 0f 100f)
animationRange = interval 10 50 --Set range to frames 10 to 50
(interval 10f 50f)
animationRange.start --Get the start frame of the range
10f
animationRange.end --Get the end frame of the range
50f
--To change the end frame of the interval only:
animationRange = interval animationRange.start 90f
(interval 10f 90f)