# File: chaos2.py
# A simple program illustrating chaotic behavior
#
# This one does error checking on the input
#
# Matt Bishop, ECS 10, Winter 2012
#

# announce what the program does
print("This program illustrates a chaotic function")

# ask for a number, but be suspicious
try:
    # ask, and convert it to a float
    x = float(input("Enter a number between 0 and 1: "))
except ValueError:
    # oops . . . didn't work; say so
    print("You need to enter a real (decimal) number between 0 and 1")
else:
    # got it!
    print("x =", x)
    #
    # check to be sure it meets he requirements
    #
    if 0 < x and x < 1:
        # it does
        #
        # now apply the chaotic function 100 times
        #
        for i in range(100):
            x = 3.9 * x * (1 - x)
            print(x)
    else:
        # it doesn't -- complan and leave
        print("Your input is not between 0 and 1")