"""This module contains a code example related to
Think Python, 2nd Edition
by Allen Downey
http://thinkpython2.com
Copyright 2015 Allen Downey
License: http://creativecommons.org/licenses/by/4.0/
"""
from __future__ import print_function, division
class Point:
"""Represents a point in 2-D space.
attributes: x, y
"""
def print_point(p):
"""Print a Point object in human-readable format."""
print('(%g, %g)' % (p.x, p.y))
class Rectangle:
"""Represents a rectangle.
attributes: width, height, corner.
"""
def find_center(rect):
"""Returns a Point at the center of a Rectangle.
rect: Rectangle
returns: new Point
"""
p = Point()
p.x = rect.corner.x + rect.width/2.0
p.y = rect.corner.y + rect.height/2.0
return p
def grow_rectangle(rect, dwidth, dheight):
"""Modifies the Rectangle by adding to its width and height.
rect: Rectangle object.
dwidth: change in width (can be negative).
dheight: change in height (can be negative).
"""
rect.width += dwidth
rect.height += dheight
def main():
blank = Point()
blank.x = 3
blank.y = 4
print('blank', end=' ')
print_point(blank)
box = Rectangle()
box.width = 100.0
box.height = 200.0
box.corner = Point()
box.corner.x = 0.0
box.corner.y = 0.0
center = find_center(box)
print('center', end=' ')
print_point(center)
print(box.width)
print(box.height)
print('grow')
grow_rectangle(box, 50, 100)
print(box.width)
print(box.height)
if __name__ == '__main__':
main()
