6.00.1x - Week 5

5.9.1 Object Oriented Programming
Object: 3 pieces: type, internal data representation, and set of procedures for interaction with the object
Instance is a particular type of object. 1234 is an instace of an int, a = 'hello' is an instance of a string
Data abstraction: represent internal data (private) using attributes, interface for interacting with object through methods
Advantages of OOP: bundle data into packages, divide-and-conquer development, and ability to reuse code

5.9.2 Class Instances
class Coordinate(object):

  • class: class definition
  • class name: Coordinate
  • class parent: object

5.9.3 Methods
def __init__(self, attr): special method (constructor) to create an instance and initialize data (optional)
__str__: equivalent to toString() in other languages to print custom string for class
representational invariant: enforce a particular rule by code

5.9.5 Why OOP?

5.9.6 Hierarchies

5.9.7 Class Variables

5.9.9 Generators
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