def __init__(self, locations, xy=None, randomize=True):
self.size = len(locations)
if xy is not None:
self.xy = xy
else:
self.xy = True
start = 0
end = self.size - 1
if self.size % 2 == 0:
median = self.size / 2 - 1
else:
median = self.size / 2
if start < end:
self.loc = Location.partition_around_median(locations, self.xy, randomize)
if start < median:
self.left = TwoDTree(locations[:median], not self.xy, randomize)
else:
self.left = None
if median < end:
self.right = TwoDTree(locations[median + 1:], not self.xy, randomize)
else:
self.right = None
elif start == end:
self.loc = locations[start]
self.left = self.right = None
else:
self.loc = self.left = self.right = None
