Classes (Part 2)

constructor method

• allows us to set unique values for the class variable's when we create an instance (while a class definition will always have the same value)

__init__()

• need to add 'self' for the first parameter

class Flower:
  def __init__(self, kind, color):
   self.kind = kind
   self.color = color

  def display_color(self):
    print(self.color)

rose_flower = Flower("rose", "red")
print(rose_flower.kind)
rose_flower.display_color()

Output:

rose
red

---

class Person:
  def __init__(self, name, age):
    self.name = name
    self.age = age

  def sayHello(self):
    print("Hello")

  def sayBye(self):
    print("Bye")

teacher = Person("Emily", 24)
teacher.sayBye()

Output:

Bye

---

class Pie:
  def __init__(self, flavor, ingredients):
    self.flavor = flavor
    self.ingredients = ingredients

  def print_ingredients(self):
      for i in self.ingredients:    
      print(i)

applePie = Pie('apple', ['flour', 'eggs', 'apples', 'butter'])

applePie.print_ingredients()

Output:

flour
apples
egss
butter

---

class Book_Series:
  def __init__(self, name, books):
    self.name = name
    self.books = books

  def print_name(self):
    print(self.name)
    
  def print_books(self): 
    print(self.books)

hg = Book_Series("Hunger Games", ["The Hunger Games", "Catching Fire", "Mockingjay"])

hg.print_books()

Output:

['The Hunger Games', 'Catching Fire', 'Mockingjay']

---

class Book_Series:
  def __init__(self, name, books):
    self.name = name
    self.books = books
    self.num_books = len(books)

  def print_name(self):
    print(self.name)
    
  def print_books(self):
    print(self.books)

hg = Book_Series("Hunger Games", ["The Hunger Games", "Catching Fire", "Mockingjay"])

hg.print_books()
print(hg.num_books)

Output:

['The Hunger Games', 'Catching Fire', 'Mockingjay']
3