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Python Object-Oriented Python Instant Objects Method Arguments

Posted by Nicholas Abate
Nicholas Abate
1,643 Points

Setting Attributes

What is the effect in where an attribute is set? Does it matter if the attribute is set right after defining the class versus after defining init()? If so, why?

Nicholas Abate
Nicholas Abate
1,643 Points

This question came from a previous exercise on classes. What would be the difference between the following.

class RaceCar: laps = 0 # what is the difference between assigning laps here 

def __init__(self, color, fuel_remaining, **kwargs):
    self.fuel_remaining = fuel_remaining
    self.color = color
    self.laps = 0                                                         # vs here
    for key, value in kwargs.items():
        setattr(self, key, value)

def run_lap(self, length):
    self.fuel_remaining = self.fuel_remaining - (length * .125)
    self.laps += 1

2 Answers

Mohammad Azawi
PLUS
Mohammad Azawi
Courses Plus Student 5,631 Points
Mohammad Azawi
Mohammad Azawi
Courses Plus Student 5,631 Points 
#An instance variable is a variable which is declared in a class but outside of constructors, methods, or blocks. Instance #variables are created when an object is instantiated, and are accessible to all the constructors, methods, or blocks in the #class. Access modifiers can be given to the instance variable.

class Student:
   name = None
   class = None

#class variables :is any variable declared on class level
# which a single copy exists, 
#regardless of how many instances of the class exist.

class Student:
    def __init__(self, name, class):
        self.name = name
        self.class= class
Nicholas Abate
Nicholas Abate
1,643 Points
Nicholas Abate
Nicholas Abate
1,643 Points

In the example you just gave, would self.name be considered a class variable?

Mohammad Azawi
Mohammad Azawi
Courses Plus Student 5,631 Points

Yes it is.

And about self.laps = 0

you just set the car laps to zero for every car you make from that class.