""" A 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. Author: Walker M. White (wmw2) Date: October 1, 2017 (Python 3 Version) """ import math class Point(object): """ A class to represent a point in 3D space INSTANCE ATTRIBUTES: 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 attribute self.y = y # y is parameter, self.y is attribute self.z = z # z is parameter, self.z is attribute def __str__(self): """ Returns: this Point as a string '(x, y, z)' """ return '('+str(self.x)+', '+str(self.y)+', '+str(self.z)+')' def __repr__(self): """ Returns: unambiguous representation of Point """ return str(self.__class__)+str(self) def __eq__(self,other): """ Returns: True if other is a point equal to this one. Parameter other: The point to compare Precondition: other is a Point """ assert type(other) == Point, repr(other)+' is not a Point' return self.x == other.x and self.y == other.y and self.z == other.z def __add__(self,other): """ Returns: A new point that is the pointwise sum of self and other Parameter other: The point to add Precondition: other is a Point """ assert type(other) == Point, repr(other)+' is not a Point' return Point(self.x + other.x, self.y + other.y, self.z + other.z) def distance(self,other): """ Returns: Distance from self to other Parameter other: The point to compare Precondition: other is a Point """ assert type(other) == Point, repr(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)