Welcome to CS1315. Click on the python to add comments. Looking for the book? They have it at the Engineer's Bookstore at 748 Marietta St NW. Here is there website: http://www.engrbookstore.com/ - Monica
	Hotspots: Slides and Code • TA Corner • Comments? • Announcements • FAQ • Static Webspace

tree

# A tree-drawing function demonstrating recursion.
# Adapted from a Logo program in Abelson and Di Sessa's "Turtle Geometry"
# (1980, p. 83)

import time

# Initialize a turtle in the center, near the bottom of the world
def init():
  width = 1000
  height = 700
  world = makeWorld(width, height)
  t = makeTurtle(world)
  penUp(t)
  moveTo(t, int(width/2), int(5*height/6))
  penDown(t)
  return t

import random
# Recursive function to draw a branch.
def branch(bud, length, level):

  # The base case.
  if level <= 0:
    return

  # The recursive case: spawn two branches 45 degrees left and right of heading
  # and one third as long as the branch we are currently on
  forward(bud, length)
  turn(bud, -45)
  branch(bud, 2*length/3, level-1)
  turn(bud, 90)
  branch(bud, 2*length/3, level-1)
  turn(bud, -45)
  forward(bud, -length)
  time.sleep(0.5)

# This is the top-level function.
# Try it with startingLength=100 and levels=8 and experiment from there.
def growTree(startingLength, levels):
  b = init()
  branch(b, startingLength, levels)

Link to this Page

• Slides and Code- Spring 2008 last edited on 23 April 2008 at 11:00 am by lawn-128-61-23-153.lawn.gatech.edu