# futval_graph_1.py
#
# Plots an investment 10 years into the future,
# using Zelle's graphics package.
#
# Based closely on code from Zelle's Python book.
#
# Jim M, Sep 2010
#

from graphics import *
    
def main():
    print "This program plots the growth of a 10 year investment."

    principal = input("Enter the initial principal (e.g. 1000) : ")
    apr = input("Enter the annualized interest rate (e.g. 0.25) : ")

    # Create the window, and put some text labels along the axis.
    window = GraphWin("Investment Growth Chart", 480, 360)
    window.setBackground("white")
    window.setCoords(-1.75, -200, 11.5, 10400)
    Text(Point(-1, 0),     ' 0.0K').draw(window)
    Text(Point(-1, 2500),  ' 2.5K').draw(window)
    Text(Point(-1, 5000),  ' 5.0K').draw(window)
    Text(Point(-1, 7500),  ' 7.5k').draw(window)
    Text(Point(-1, 10000), '10.0K').draw(window)

    # Draw a bar for the original principal.
    bar = Rectangle(Point(0, 0), Point(1, principal))
    bar.setFill("green")
    bar.setWidth(2)
    bar.draw(window)

    # And then do the same for each of 10 years.
    for year in range(1, 11):
        principal = principal * (1 + apr)
        bar = Rectangle(Point(year, 0), Point(year+1, principal))
        bar.setFill("green")
        bar.setWidth(2)
        bar.draw(window)

    raw_input("Press <Enter> to quit.")
    window.close()

main()