Python code doesn't execute. No errors showed

Question

I don't know what's wrong with my code. It would just not execute. Nothing happens, no errors occur. I can't figure it out. If someone can tell me what I have done wrong, please do so and I will be grateful.

class Money (object):
    def __init__ (self, euro, cent):
      self.euro = euro
      self.cent = cent

    def __str__ (self):
        if self.cent >= 100:
            r = self.cent / 100
            self.cent = self.cent % 100
            self.euro = self.euro + r
            return ("%d EUR & %d cents") % (self.euro, self.cent)
        else:
            return ("%d EUR & %d cents") % (self.euro, self.cent)

    def changeCent (self):
        #100 c = 1 E
        cents = self.euro * 100
        self.cent = self.cent + cents
        return self.cent

    def changeSum (self, euros):
        #1 E = 100 c
        euros = self.cent / 100
        self.euro = self.euro + euros
        return self.euro

    def debt (self, years, rate):
        value = Money()
        multiply = rate * years * 12 / 100
        value.euro = self.euro * multiply
        value.cent = self.cent * multiply
        if value.cent > 100:
            euro_ = value.cent / 100
            value.cent = value.cent - 100
            value.euro = value.euro + euro_
        return value

def main():
    x = Money()
    x.euro = int(input("Type in your EURO ammount: \n"))
    x.cent = int(input("Type in your CENT ammount: \n"))
    print (x)

You've defined a class and a `main` function. Are you running the function? — Bill the Lizard, May 24 '18 at 13:12
You should have started with a `Hello World` program and extended it from there. — quamrana, May 24 '18 at 13:13
Uhm, I dunno. I thought 'def main()' was to create a border between the class and its methods/functions and the main program itself. — Angel Draghici, May 24 '18 at 13:14
@AngelDraghici A class is something that helps organize/encapsulate logic inside of a script - same with methods (like `main()`). But for the script to run, you have to call some method, or class property. Otherwise, you've written a function library - not a script that does anything on its own. — alex, May 24 '18 at 13:15

score 6 · Answer 1 · answered May 24 '18 at 13:16

In python, main is not a special function (unlike C, for example).

You need to explicitly call main() in your script.

A common idiom is to only do this if your file is run as a script (as opposed to being imported):

if __name__ == "__main__":
    main()

See the documentation for how this works

Flaming_Dorito · Accepted Answer · 2018-05-24T13:18:40.410

You defined the main function, but you never call it.

add main() to the end of your code.

It then runs but there are errors, to fix the errors, change your main() function to

def main()
    euro = int(input("Type in your EURO ammount: \n"))
    cent = int(input("Type in your CENT ammount: \n"))
    x = Money(euro, cent)
    print (x)

Full working code:

class Money (object):
    def __init__ (self, euro, cent):
      self.euro = euro
      self.cent = cent

    def __str__ (self):
        if self.cent >= 100:
            r = self.cent / 100
            self.cent = self.cent % 100
            self.euro = self.euro + r
            return ("%d EUR & %d cents") % (self.euro, self.cent)
        else:
            return ("%d EUR & %d cents") % (self.euro, self.cent)

    def changeCent (self):
        #100 c = 1 E
        cents = self.euro * 100
        self.cent = self.cent + cents
        return self.cent

    def changeSum (self, euros):
        #1 E = 100 c
        euros = self.cent / 100
        self.euro = self.euro + euros
        return self.euro

    def debt (self, years, rate):
        value = Money()
        multiply = rate * years * 12 / 100
        value.euro = self.euro * multiply
        value.cent = self.cent * multiply
        if value.cent > 100:
            euro_ = value.cent / 100
            value.cent = value.cent - 100
            value.euro = value.euro + euro_
        return value

def main():
    euro = int(input("Type in your EURO ammount: \n"))
    cent = int(input("Type in your CENT ammount: \n"))
    x = Money(euro, cent)
    print (x)

main()

@AngelDraghici If my answer solved your problem, please accept my answer with the green tick mark near the upvote and downvote buttons. Thank you! :D — Flaming_Dorito, May 24 '18 at 13:21

score 2 · Answer 3 · answered May 24 '18 at 13:17

The pythonic way of getting a result here would be to add following lines to the file:

if __name__=='__main__':
    main()

It checks, whether you are calling the script as the main script. Currently you only define the function main, but you never call it.

score 1 · Answer 4 · answered May 24 '18 at 13:13

1

You should run the function main()

answered May 24 '18 at 13:13

shubham johar · Answer 5 · 2018-05-24T13:20:25.017

0

To execute the function type main() at the bottom. You did almost everything except calling the function.

One more mistake

your constructor def __init__ (self, euro, cent):expects two parameters. You are not passing any value to it.

To fix that change to:

def __init__ (self, euro=0, cent=0):

which assigns default value of 0 to both euro and cent

edited May 24 '18 at 13:20

answered May 24 '18 at 13:13

shubham johar

268
1
9

Thank you, misunderstanding the `main()` method with the main from C/C++. – Angel Draghici May 24 '18 at 13:17
Adding the `euro=0, cent=0` Is not the right solution – Flaming_Dorito May 25 '18 at 18:44

Python code doesn't execute. No errors showed

5 Answers5