# calculator with all buttons

import simplegui

# intialize globals

store = 0

operand = 0

# event handlers for calculator with a store and operand

def output():

"""prints contents of store and operand"""

print "Store = ", store

print "Operand = ", operand

print ""

def swap():

""" swap contents of store and operand"""

global store, operand

store, operand = operand, store

output()

def add():

""" add operand to store"""

global store

store = store + operand

output()

def sub():

""" subtract operand from store"""

global store

store = store - operand

output()

def mult():

""" multiply store by operand"""

global store

store = store * operand

output()

def div():

""" divide store by operand"""

global store

store = store / operand

output()

def enter(text_input):

""" enter a new operand"""

global operand

operand = float(text_input)

output()

# create frame

f = simplegui.create_frame("Calculator",300,300)

# register event handlers and create control elements

f.add_button("Print", output, 100)

f.add_button("Swap", swap, 100)

f.add_button("Add", add, 100)

f.add_button("Sub", sub, 100)

f.add_button("Mult", mult, 100)

f.add_button("Div", div, 100)

f.add_input("Enter", enter, 100)

# get frame rolling

f.start()