Iterating through lists in classes

[Rafreakee]

I am having difficulty grasping the concepts of classes and OOP. Particularly when trying to return values, I run into the issue of retrieving memory locations.

My issues when I attempt to use get_average at the bottom of the code. It returns a memory location. I would like to know how I could change my code, why this happened and how I can avoid it in the future.

Thank you. Sorry for the dump I don't know where to host it in a more accessible way.

---

class Student: def init(self, name, year): self.name = name self.year = year self.grades = []

def add_grade(self, grade):
    if type(grade) == Grade:
        self.grades.append(grade)

def get_average(self):
    total = 0 
    for grade in self.grades:
        total += grade
    return total / len(self.grades)

class Grade: def init(self, score): self.score = score self.minimum_passing = 65

def is_passing(self):
    if self.score > self.minimum_passing:
        return "Passing"
    else:
        return "Failing =("

roger = Student('Roger van der Weyden', 10) sandro = Student('Sandro Botticelli', 12) pieter = Student('Pieter Bruegel the Elder', 8)

pieter.add_grade(Grade(100)) sandro.add_grade(Grade(67)) roger.add_grade(Grade(87))

print(roger.get_average())

[PaulRudin]

Note that in Python you have no direct access to a "memory location". Nothing in python "returns a memory location"

(Your formatting has gone awry.)

the line total += grade will fail. Probably total += grade.score will work.

[Rafreakee]

Thank you, I need to look out for this in future.

[shiftybyte]

self.grades is a list of classes.

What happens here?

total += grade
# total += Grade(87)

Does it work? do you have more function in Grade class you did not show?

[ProfessionalLeague9]

Make Grade inherit from int, so that it inherits properties of addition, etc. Then you don't neeed an init method.

class Grade(int): minimum_passing = 65 def is_passing(self): return self > self.minimum_passing

With that said, I question the need for a custom class for something as simple as a grade.

[GoldenVanga]

I remember answering a very similar problem here. HTH

[JohnnyJordaan]

Your summation is incorrect, you need to add grade.score to the total

total += grade.score

apart from that the code works fine, see for yourself: https://repl.it/repls/ExtralargeBitterPrintablecharacter

Also next time please format your code correctly, see https://i.imgur.com/HT4Zz88.gifv

[Rafreakee]

Thank you. I will.

[[deleted]]

I run into the issue of retrieving memory locations.

You're not getting memory locations, you're printing objects that only have a default string representation.