### 7.12. `Pt.__cmp__()`

: Compare two points

The intent of this method is to determine whether two
points coincide. The inequality cases are less useful,
but we basically use `x`

as
the primary sort key and `y`

as the secondary key.

homcoord.py

# - - - P t . _ _ c m p _ _
def __cmp__(self, other):
'''Compare two points.
'''
return cmp(self.xy(), other.xy())