在 Python 中创建基本菜单

Question

import circle
pi = 3.1415

def main():
        
        area(radius)
        circumference(radius)

def menu():
        print("Type a for area of circle")
        print("Type b for circumference of a circle")
        print("Type c to END PROGRAM")     
loop=True

while loop:
        menu()
        choice = input('Please enter your choice: ')

        if choice=="a":
                radius = float(input ("Input the radius of the circle : "))
                print(circle.area(radius))
        elif choice=="b":
                radius = float(input ("Input the radius of the circle : "))
                print(circle.circumference(radius))
        else:
                print("Goodbye!")
                

def area(radius):
    return pi * radius**2


def circumference(radius):
    return 2 * pi * radius

main()

I am trying to make a simple menu that either gives the user one of the instructed outputs if they type one of the three letters. So if I were to type the letter 'a', I would be asked to input the radius of the circle and then be given the area in return. I hope that makes sense.

However, when I try to test this menu, I am told none of the letters are defined, so I'm kind of confused why it's not working.

Answer 1

You are very close, just a couple of things are derailing your program.

First: Because you have created functions, you don't need to import a 'circle' mod. Where does this come from? Are you trying to define a Class object or modual?

Second: Your functions need to be defined in the program BEFORE they are called. You had them placed after, which was causing errors.

Third: You forgot to set loop to False when "c" is entered. Lacking this, then loop never ends.

Hope this helps!

def area(radius):
    return pi * radius**2


def circumference(radius):
    return 2 * pi * radius

#import circle
pi = 3.1415

def main():
        
        area(radius)
        circumference(radius)

def menu():
        print("Type a for area of circle")
        print("Type b for circumference of a circle")
        print("Type c to END PROGRAM")     
loop=True

while loop:
        menu()
        choice = input('Please enter your choice: ')

        if choice=="a":
                radius = float(input ("Input the radius of the circle : "))
                print(area(radius))
        elif choice=="b":
                radius = float(input ("Input the radius of the circle : "))
                print(circumference(radius))
        else:
                print("Goodbye!")
                loop = False