Models of Motion

# triangle.pyw
# Interactive graphics program to draw a triangle

from graphics import *

def main():
    win = GraphWin("Draw a Triangle")
    win.setCoords(0.0, 0.0, 10.0, 10.0)
    message = Text(Point(5, 0.5), "Click on three points")
    message.draw(win)

    # Get and draw three vertices of triangle
    p1 = win.getMouse()
    p1.draw(win)
    p2 = win.getMouse()
    p2.draw(win)
    p3 = win.getMouse()
    p3.draw(win)

    # Use Polygon object to draw the triangle
    triangle = Polygon(p1,p2,p3)
    triangle.setFill("peachpuff")
    triangle.setOutline("cyan")
    triangle.draw(win)

    # Wait for another click to exit
    message.setText("Click anywhere to quit.")
    win.getMouse()

main()

# convert_gui.pyw
# Program to convert Celsius to Fahrenheit using a simple
#   graphical interface.

from graphics import *

def main():
    win = GraphWin("Celsius Converter", 300, 200)
    win.setCoords(0.0, 0.0, 3.0, 4.0)
   
    # Draw the interface
    Text(Point(1,3), "   Celsius Temperature:").draw(win)
    Text(Point(1,1), "Fahrenheit Temperature:").draw(win)
    input = Entry(Point(2,3), 5)
    input.setText("0.0")
    input.draw(win)
    output = Text(Point(2,1),"")
    output.draw(win)
    button = Text(Point(1.5,2.0),"Convert It")
    button.draw(win)
    Rectangle(Point(1,1.5), Point(2,2.5)).draw(win)

    # wait for a mouse click
    win.getMouse()

    # convert input
    celsius = eval(input.getText())
    fahrenheit = 9.0/5.0 * celsius + 32

    # display output and change button
    output.setText("%0.1f" % fahrenheit)
    button.setText("Quit")

    # wait for click and then quit
    win.getMouse()
    win.close()
   
main()

# addinterest1.py
#    Program illustrates failed attempt to change value of a parameter

def addInterest(balance, rate):
    newBalance = balance * (1+rate)
    balance = newBalance

def test():
    amount = 1000
    rate = 0.05
    addInterest(amount, rate)
    print amount
   
test()

 # addinterest2.py
#    Illustrates use of return to change value in calling program.

def addInterest(balance, rate):
    newBalance = balance * (1+rate)
    return newBalance

def test():
    amount = 1000
    rate = 0.05
    amount = addInterest(amount, rate)
    print amount

test()

# addinterest3.py
#    Illustrates modification of a mutable parameter (a list).

def addInterest(balances, rate):
    for i in range(len(balances)):
        balances[i] = balances[i] * (1+rate)

def test():
    amounts = [1000, 2200, 800, 360]
    rate = 0.05
    addInterest(amounts, 0.05)
    print amounts

test()