[Tutor] I cant fix this bug

[Mitya Sirenef]

On 12/18/2012 08:05 PM, Gina wrote:
> I have Python version 3.
> when the program begins, it prints out the main menu and then asks you 
> for your choice - just like it is supposed to
> you enter your choice, and the next menu pops up, and below the menu 
> it says "None" on the line before your next choice is asked for
> i dont know why it does this or how to make it go away
>
> sorry the menu looks funny(they are supposed to be shapes)
> i didnt include the code for all of the functions but the same thing 
> happens for each of the four choices
>
> CODE BEGINS HERE:
>
> def parallelogram_area(side1, side2):
>     "find the area of a parallelogram"""
>     solution1 = float(side1 * side2)
>     return solution1
>
> def quadrilateral_perimeter(side1, side2, side3, side4):
>     """find the perimeter of a quadralateral"""
>     solution1 = float(side1 + side2 + side3  + side4)
>     return solution1
>
> def trapezoid_area(side1, side2, height):
>     """find the area of a trapazoid"""
>     solution1 = float(side1 + side2)
>     solution2 = float((height)/2)
>     solution3 = float(solution1 * solution2)
>     return solution3
>
> def menu_quad():
>     """Display menu for quadrilaterals"""
>     print(
>     """
>         Quadrilaterals
>
>     0 - Return to main menu
>     1 - Parallelogram (area)
>     2 - Trapezoid (area)
>     3 - Quadrilateral(perimeter)
>     """
>     )
>
> choice = None
> while choice != "0":
>     print(
>     """
>     Menu
>
>     0 - Exit
>
>     1 - Quadrilaterals        3 - Circles
>       _________________             **
>      |                 |         ********
>      |                 |       ************
>      |                 |      **************
>      |                 |      **************
>      |                 |       ************
>      |_________________|         ********
>                                     **
>      2 - Triangles            4 - 3D
>            /\                    /|\
>           /  \                  / | \
>          /    \                /  |  \
>         /      \              /   |  /
>        /        \            /    | /
>       /__________\          /_____|/
>
>     """
>     )
>
>     choice = input("Choice: ")
>
>     if choice == "0":
>         print("Good-bye.")
>
> #main
>     if choice == "1":
>         #quadrilaterals
>         print(menu_quad())
>
>         quad_choice = input("Choice: ")
>
>         if quad_choice == "0":
>             print()
>
>         if quad_choice == "1":
>             #parallelogram
>             side1 = float(input("Side 1: "))
>             side2 = float(input("Side 2: "))
>             area = parallelogram_area(side1, side2)
>             print("The area of the parallelogram is", area)
>
>         if quad_choice == "2":
>             #trapezoid
>             side1 = float(input("Side 1: "))
>             side2 = float(input("Side 2: "))
>             height = float(input("height: "))
>             area = trapezoid_area(side1, side2, height)
>             print("The area of the trapezoid is", area)
>
>         if quad_choice == "3":
>             #quadrilateral
>             side1 = float(input("Side 1: "))
>             side2 = float(input("Side 2: "))
>             side3 = float(input("Side 3: "))
>             side4 = float(input("Side 4: "))
>             perim = quadrilateral_perimeter(side1, side2, side3, side4)
>             print("The perimeter of the quadrilateral is", perim)
>
>         else:
>             print("Sorry, that is not a valid choice :(")
>
> input("Press enter to exit.")
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It looks like you have print(menu_quad()) which prints
the return value of that function. When function has no
explicit return value in python, it returns None.

You probably mean to return the string in that function
instead of printing it there.

  - mitya

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Lark's Tongue Guide to Python: http://lightbird.net/larks/