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print "c =",c
print "c =",c


</pre>
</pre>



Revision as of 18:29, 12 September 2007

Pippy is an activity for learning how to program with Python. It looks like this:

Pippy.png

Examples

Please add examples here, or modify the existing ones!

Math

Apples

Author: Madeleine Ball

print "Let's do math!"

print "On Monday I picked 22 apples. On Tuesday I picked 12."

print "Now I have: ", 22 + 12

print "My brother says he picked twice as many apples last week."

print "This means he picked: ", (22 + 12) * 2

print "I have 3 friends I would like to give apples."

print "One third of my apples is about: ", (22 + 12) / 3

print "Or, more exactly: ", (22.0 + 12.0) / 3.0

Pascal

Author: Madeleine Ball

# Pascal's triangle
lines = 8

vector = [1]

for i in range(1,lines+1):
  vector.insert(0,0)
  vector.append(0)

for i in range(0,lines):
  newvector = vector[:]
  for j in range(0,len(vector)-1):
    if (newvector[j] == 0):
      print "  ",
    else:
      print "%2d" % newvector[j],
    newvector[j] = vector[j-1] + vector[j+1]
  print
  vector = newvector[:]

Sierpinski triangle

Author: Madeleine Ball

Modification of the Pascal's triangle program to produce Sierpinski triangles.

size = 5
modulus = 2

lines = modulus**size

vector = [1]
for i in range(1,lines+1):
  vector.insert(0,0)
  vector.append(0)

for i in range(0,lines):
  newvector = vector[:]
  for j in range(0,len(vector)-1):
    if (newvector[j] == 0):
      print " ",
    else:
      remainder = newvector[j] % modulus
      if (remainder == 0):
        print "O",
      else:
        print ".",
    newvector[j] = vector[j-1] + vector[j+1]
  print
  vector = newvector[:]

Times1

Author: Chris Ball

for i in range(1,13):
    print i, "x 4 =", (i*4)

Times2

Author: Chris Ball

number = input("Which times table? ")
for i in range(1,13):
    print i, "x", number, "=", i*number

Fibonacci Series

Author : Rafael Ortiz

a, b = 0, 1
while b < 1001:
     print b,
     a, b = b, a+b

Pythagoras

Author : Rafael Ortiz

import math
from math import sqrt

print "This is the Pythagoras Theorem"
a=float(raw_input("Type a ="))
b=float(raw_input("Type b ="))

c=sqrt((a*a)+(b*b))

print "c =",c

Factorize

Author: Reinier Heeres

import math
import sys

orignum = input("Enter a number to factorize ")

factors = []
num = orignum
i = 2
while i <= math.sqrt(num):
    if num % i == 0:
        factors.append(i)
        num /= i
        i = 2
    elif i == 2:
        i += 1
    else:
        i += 2

factors.append(num)

if len(factors) == 1:
    print "%d is prime" % orignum
else:
    sys.stdout.write("%d is %d" % (orignum, factors[0]))
    for fac in factors[1:]:
        sys.stdout.write(" * %d" % fac)
    print

Python

Function

Author: Chris Ball

def square(x): 
    print x * x

square(3)
square(4)

If

Author: Chris Ball

number = input("Enter a number: ")

if number > 5:
    print "Greater than 5"
elif number < 5:
    print "Less than 5"
else:
    print "Number is 5!"

Recursion

Author: Mel Chua

# Note this assumes you understand functions and if-else.
def countbackwards(number):
    print "I have the number", number
    if number > 0:
        print "Calling countbackwards again!"
        countbackwards(number-1)
    else:
        print "I am done counting"

number = input("Enter a number: ")
countbackwards(number):

String

Hello1

Author: Chris Ball

print "Hello everyone!"

Hello2

Author: Chris Ball

name = raw_input("Type your name here: ")
print "Hello " + name + "!"

Graphics

Jump

Author: C. Scott Ananian

# both of these functions should be in the 'basic' package or some such
def clear_scr():
    print '\x1B[H\x1B[J' # clear screen, the hard way.
def wait():
    import time
    time.sleep(0.1)

# jumping man!
# was having to escape the backslash which was rather unfortunate, 
# now using python's r" strings which were meant for regex's
# i didn't have to do that in C64 BASIC
for i in xrange(0,50):
    clear_scr()
    print r"\o/"
    print r"_|_"
    print r"   "
    wait()
    
    clear_scr()
    print r"_o_"
    print r" | "
    print r"/ \"
    wait()
    
    clear_scr()
    print r" o "
    print r"/|\"
    print r"| |"
    wait()
    
    clear_scr()
    print r"_o_"
    print r" | "
    print r"/ \"
    wait()