Missing required potential argument in function call Python

Question

I'm just starting to learn Python, and was writing a calculator program with two different files to get the concept of calling classes and functions down. The file with the mathmatical operations in a class looks as such:

class standardOpperations:
def __init__(self, primaryNumber, secondaryNumber):
    primaryNumber.self = primaryNumber
    secondaryNumber.self = secondaryNumber
def addition(self, primaryNumber, secondaryNumber):
    print(primaryNumber, "+", secondaryNumber, "=", primaryNumber.self+secondaryNumber)
def subtraction(self, primaryNumber, secondaryNumber):
    print(primaryNumber, "-", secondaryNumber, "=", primaryNumber-secondaryNumber)
def multiplication(self, primaryNumber, secondaryNumber):
    print(primaryNumber, "*", secondaryNumber, "=", primaryNumber * secondaryNumber)
def division(self, primaryNumber, secondaryNumber):
    print(primaryNumber, "/", secondaryNumber, "=", primaryNumber / secondaryNumber)

In a separate file, I tried to call this object (specifically the first function) in this line of code:

number01 = float(input("Please input a number here: "))
number02 = float(input("Please input a second number here: "))
addObj = standardOpperations.addition(number01,number02)

My issue is that upon running it, I get an error stating that I am missing a required potential argument, even though the function only uses two numbers. I'd really appreciate any help I can get in spotting my mistake, and helping the program work. Thanks all!

hint: you're calling an instance method like a normal function (note the required self argument in instance methods - this self argument is only automatically and implicitly passed as the first argument when called as instance method) — Phu Ngo
– Phu Ngo, Commented Feb 23, 2020 at 6:13

alec · Accepted Answer · 2020-02-23 05:22:51Z

1

Since you are treating each function as a static method, remove the constructor and the word self anywhere in the class.

class standardOpperations:

    def addition(primaryNumber, secondaryNumber):
        print(primaryNumber, "+", secondaryNumber, "=", primaryNumber+secondaryNumber)
    def subtraction(primaryNumber, secondaryNumber):
        print(primaryNumber, "-", secondaryNumber, "=", primaryNumber-secondaryNumber)
    def multiplication(primaryNumber, secondaryNumber):
        print(primaryNumber, "*", secondaryNumber, "=", primaryNumber * secondaryNumber)
    def division(primaryNumber, secondaryNumber):
        print(primaryNumber, "/", secondaryNumber, "=", primaryNumber / secondaryNumber)


>>> standardOpperations.addition(1,2)
1 + 2 = 3

answered Feb 23, 2020 at 5:22

alec

6,1321 gold badge9 silver badges20 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

evanr50 Over a year ago

Thanks! That solved my problem. Now I have to ask though, what does the init function do for a function? I was taught to use that whenever I made a function in class, but there are evidently places where it shouldn't be used. Is there a specific purpose it is typically used for? Thank you again for helping me solve my issue

Ranjita Shetty · Accepted Answer · 2020-02-23 05:34:07Z

I have corrected your code.

Please find the working code below

class standardOpperations:
  def __init__(self, primaryNumber, secondaryNumber):
      self.primaryNumber = primaryNumber
      self.secondaryNumber = secondaryNumber
  def addition(self):
      print(self.primaryNumber, "+", self.secondaryNumber, "=", self.primaryNumber+self.secondaryNumber)
  def subtraction(self):
      print(self.primaryNumber, "-", self.secondaryNumber, "=", self.primaryNumber-self.secondaryNumber)
  def multiplication(self):
      print(self.primaryNumber, "*", self.secondaryNumber, "=", self.primaryNumber * self.secondaryNumber)
  def division(self):
      print(self.secondaryNumber, "=", self.primaryNumber / self.secondaryNumber)

number01 = float(input("Please input a number here: "))
number02 = float(input("Please input a second number here: "))
addObj = standardOpperations(number01,number02)
addObj.addition()

Collectives™ on Stack Overflow

Missing required potential argument in function call Python

2 Answers 2

1 Comment

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Related