>>> from moving import *

>>> Interval().empty()
True
>>> Interval(0,1).empty()
False
>>> Interval(0,1).length()
1
>>> Interval(23.2,24.9).length()
1.6999999999999993
>>> Interval(10,8).length()
0

>>> TimeInterval(0,1).length()
2
>>> TimeInterval(10,8).length()
0

>>> Point(3,4)-Point(1,7)
(2.000000,-3.000000)

>>> Point(3,2).norm2Squared()
13

>>> Point.distanceNorm2(Point(3,4),Point(1,7))
3.6055512754639891