More Functions

These are bonus programs! They are meant to be challenging. They are not listed in order of difficulty, so choose whichever programs sound interesting!

Fibonacci

File: fibonacci.py

In the 13th century, the Italian mathematician Leonardo Fibonacci—as a way to explain the geometric growth of a population of rabbits—devised a mathematical sequence that now bears his name. The first two terms in this sequence, Fib(0) and Fib(1), are 0 and 1, and every subsequent term is the sum of the preceding two. Thus, the first several terms in the Fibonacci sequence look like this:

Fib(0) = 0
Fib(1) = 1
Fib(2) = 1 (0 + 1)
Fib(3) = 2 (1 + 1)
Fib(4) = 3 (1 + 2)
Fib(5) = 5 (2 + 3)

Write a program that displays the terms in the Fibonacci sequence. This will require writing a function that takes as a parameter, the value of the max term that should be printed. The main() function has already been written:

def main():
    fibonacci(60)
    fibonacci(500)

This would produce an output of:

0
1
1
2
3
5
8
13
21
34
55
0
1
1
2
3
5
8
13
21
34
55
89
144
233
377

Draw Centered Label

File: centered_label.py

Write a program that draws a centered label. The text for the label should be a parameter to a function, as should be its font name and font size. The main() function is already written for you:

def main():
    canvas = Canvas()
    canvas.set_canvas_title("Centered Label")
    draw_centered_label(canvas, "Coding Rocks!", "Courier", 40)
    canvas.mainloop()

This would produce an output like below:

Speedy Shopper

File: speedy_shopper.py

Items on sale at a store are listed with the percent off for that item. For example, an item that originally costs 100 Turkish Lira at 25% off would cost 75 Turkish Lira. Write a program that calculates the cost of an on-sale item. Specifically, write a function that takes in a price, and the percent off for that item. This function should return the new price for that item. The mai() function is already written for you:

def main():
    print(calculate_price(100.32, 0.25))
    print(calculate_price(53.27, 0.15))

This would produce an output like below:

75.24
45.2795