class parameters python code example

Example 1: declare class python

# To create a simple class:
class Shape:
  	def __init__():
      	print("A new shape has been created!")
      	pass
    
    def get_area(self):
		pass

# To create a class that uses inheritance and polymorphism
# from another class:
class Rectangle(Shape):
  
	def __init__(self, height, width): # The constructor
    	super.__init__()
        self.height = height
    	self.width = width

	def get_area(self):
      	return self.height * self.width

Example 2: call instance class python

# define class
class example:
# define __call__ function
   def __call__(self):
       print("It worked!")
# create instance
g = example()
# when attempting to call instance of class it will call the __class method
g()
# prints It worked!

Example 3: python class

class Animal(object): # Doesn't need params but put it there anyways.
    def __init__(self, species, price):
        self.species = species # Sets species name
        self.price = price # Sets price of it
    
    def overview(self): # A function that uses the params of the __init__ function
        print(f"This species is called a {self.species} and the price for it is {self.price}")

class Fish(Animal): # Inherits from Animal
    pass # Don't need to add anything because it's inherited everything from Animal
 
salmon = Fish("Salmon", "$20") # Make a object from class Fish
salmon.overview() # Run a function with it
dog = Animal("Golden retriever", "$400") # Make a object from class Animal
dog.overview() # Run a function with it

Example 4: python class

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

    def speak(self):
        print("Hi I'm ", self.name, 'and I am', self.age, 'Years Old')

JUB0T = Dog('JUB0T', 55)
Friend = Dog('Doge', 10)
JUB0T.speak()
Friend.speak()

Example 5: class methods parameters python

class Foo          (object):
    # ^class name  #^ inherits from object

    bar = "Bar" #Class attribute.

    def __init__(self):
        #        #^ The first variable is the class instance in methods.  
        #        #  This is called "self" by convention, but could be any name you want.
        #^ double underscore (dunder) methods are usually special.  This one 
        #  gets called immediately after a new instance is created.

        self.variable = "Foo" #instance attribute.
        print self.variable, self.bar  #<---self.bar references class attribute
        self.bar = " Bar is now Baz"   #<---self.bar is now an instance attribute
        print self.variable, self.bar  

    def method(self, arg1, arg2):
        #This method has arguments.  You would call it like this:  instance.method(1, 2)
        print "in method (args):", arg1, arg2
        print "in method (attributes):", self.variable, self.bar


a = Foo() # this calls __init__ (indirectly), output:
                 # Foo bar
                 # Foo  Bar is now Baz
print a.variable # Foo
a.variable = "bar"
a.method(1, 2) # output:
               # in method (args): 1 2
               # in method (attributes): bar  Bar is now Baz
Foo.method(a, 1, 2) #<--- Same as a.method(1, 2).  This makes it a little more explicit what the argument "self" actually is.

class Bar(object):
    def __init__(self, arg):
        self.arg = arg
        self.Foo = Foo()

b = Bar(a)
b.arg.variable = "something"
print a.variable # something
print b.Foo.variable # Foo

Example 6: class python

class A:        # define your class A
.....

class B:         # define your class B
.....

class C(A, B):   # subclass of A and B
  
obj = C() #to create instance
# issubclass(sub, sup) boolean function returns true if the given 
# subclass sub is indeed a subclass of the superclass sup

# isinstance(obj, Class) boolean function returns true if obj is an 
# instance of class Class or is an instance of a subclass of Class