# point.py # Walker M. White (wmw2) # October 7, 2012 """Module with a simple Point class. This module has a simpler version of the Point class than what we saw in previous labs. It shows off the minimum that we need to get started with a class.""" import math class Point(object): """Instance is a point in 3D space Instance variables: x: x-coordinate [float] y: y-coordinate [float] z: z-coordinate [float] """ def __init__(self,x=0.0,y=0.0,z=0.0): """Initializer: makes a new Point Precondition: x, y, and z are floats""" self.x = x # x is parameter, self.x is field self.y = y # y is parameter, self.y is field self.z = z # z is parameter, self.z is field def __str__(self): """Returns: this Point as a string '(x, y, z)'""" return '('+str(self.x)+', '+str(self.y)+', '+str(self.z)+')' def __eq__(self,other): return self.x == other.x and self.y == other.y and self.z == other.z def __add__(self,other): return Point(self.x + other.x, self.y + other.y, self.z + other.z) def __repr__(self): """Returns: unambiguous representation of Point""" return str(self.__class__)+str(self) def distanceTo(self,other): """Returns: Distance from self to other Precondition: other is a Point""" assert type(other) == Point, `other`+' is not a Point' dx = (self.x-other.x)*(self.x-other.x) dy = (self.y-other.y)*(self.y-other.y) dz = (self.z-other.z)*(self.z-other.z) return math.sqrt(dx+dy+dz)