Using inheritance in python

Question

this is my homework assignment, I saw it posted on the website before, but it looks like it was unsolved and I got a different error message than a person asking that questi

Answer 1

Look at the declaration of Executive.__init__:

def __init__(self, name, wage, yearlyBonus):

Nowhere in there does it declare a variable named salary. But when you call the superclass constructor,

    Employee.__init__(self, name, salary) 

you are asking Python to pass the value of a variable named salary as the third parameter. Python is just complaining that this variable does not exist.

I imagine you can figure out how to fix it from there. :-)

Answer 2

Yes, your init function does not have variable named salary, which gives error when you passed it in to Employee.init.

class Executive(Employee):
    def __init__(self, name, wage, yearlyBonus):
        Employee.__init__(self, name, salary) 

when you do this

executive = Executive("Kerry", 520000, 1040000)

which one correlates to the salary? passed that as the employee init method. Better if you call the Employee constructor with super

Guessing from this method

def wage(self):
        return self._salary/26   

Maybe this is what you want (not sure how to account yearlyBonus though)

 class Executive(Employee):
        def __init__(self, name, wage, yearlyBonus):
            Employee.__init__(self, name, wage * 26) 

Answer 3

Just look at the code where the error is occurring, and keep looking until you notice what doesn't match up:

def __init__(self, name, wage, yearlyBonus):
    Employee.__init__(self, name, salary) 

Answer 4

The error is pretty clear. salary is not defined in the __init__ method of Executive.

You used wage as an argument to __init__, but salary when calling __init__ of your parent class, so you should stick to one variable name:

class Executive(Employee):
    def __init__(self, name, salary, yearlyBonus):
        Employee.__init__(self, name, salary) 

Also, you can get around typing all of those parameters in each time by using *args:

class Executive(Employee):
    def __init__(self, *args, yearlyBonus):
        super(Executive, self).__init__(*args)

Use super() instead of calling the parent class's __init__ method. It makes multiple inheritance a bit easier.