Displaying variable in grahpics window from function Python 3.4

Question

I've found and edited some code to generate the nth of the Fibonacci Sequence, but my issue is with displaying it in a graphics window.

from graphics import *



def main():

    win = GraphWin("Sample Input", 300, 300)

    win.setCoords(0,0, 299, 299) # not required, just convenient



    input_prompt = Text(Point(150, 200),"Enter a positive integer")

    input_prompt.setStyle('bold italic') # not required, just convenient

    input_prompt.draw(win)



    input_integer = Entry(Point(150, 150),5)

    input_integer.setText("    ")

    input_integer.draw(win)



    win.getMouse()



    integer_number = int(input_integer.getText())  # the very line that does the input!



    running_count = 0

    for x in range(1, integer_number + 1):

        running_count = running_count + x

        def factorial(n):
            if n == 1:
                return n
            else:
                return n*factorial(n-1)

        def fibN( k ):
            k = abs( int( k ))
            if k == 0:
                fib = 0
            elif k == 1:
                fib = 1
            else:
                counter = 2  
                f0 = 0
                f1 = 1
                fib = f0 + f1
                while counter <= k:
                    fib = f0 + f1
                    f0 = f1
                    f1 = fib
                    counter += 1
            print(fib)

        fib_result = "Fibonacci", "term", "of", integer_number, "is", fibN(integer_number)

        prompt = Text(Point(150, 50), fib_result)

        prompt.draw(win) 

    result_string = "The number is "+str(running_count)+"."

#     Text objects require a string, not a number

    result = Text(Point(150, 100), result_string)

    result.draw(win)

    factorial_result = "Factorial", "of",integer_number, "is", factorial(integer_number) #brackets displayed, separated factorial, of

    prompt = Text(Point(150, 75), factorial_result)

    prompt.draw(win)      

    prompt = Text(Point(150, 25),"Click to end")

    prompt.draw(win)

    win.getMouse()

    win.close()



main()

It prints it, and it displays in the window that the Fibonacci term for N is "None". The number it prints is correct. How can I change this to display the printed number?

Answer 1

Your fibN function doesn't return anything:

def fibN( k ):
        k = abs( int( k ))
        if k == 0:
            fib = 0
        elif k == 1:
            fib = 1
        else:
            counter = 2  
            f0 = 0
            f1 = 1
            fib = f0 + f1
            while counter <= k:
                fib = f0 + f1
                f0 = f1
                f1 = fib
                counter += 1
        print(fib) #this only puts the output on the screen

For the function output (the number fib) to replace the call, you need to return fib:

 def fibN( k ):
        k = abs( int( k ))
        if k == 0:
            fib = 0
        elif k == 1:
            fib = 1
        else:
            counter = 2  
            f0 = 0
            f1 = 1
            fib = f0 + f1
            while counter <= k:
                fib = f0 + f1
                f0 = f1
                f1 = fib
                counter += 1
        return fib

Then you can do print(fibN(something)) if you want, but you can also use it in graphics like you're doing now.