OOPS in Python.ipynb

{
 "cells": [
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Object oriented programming"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Attributes\n",
    "# Function\n",
    "# Attributes + Function = Classes\n",
    "# Object\n",
    "# Encapsulation\n",
    "# Inheritance\n",
    "# Polymorphism"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [],
   "source": [
    "class className:\n",
    "    var = \"This is a class variable\"\n",
    "    def func(self):\n",
    "        print(\"I am inside the class\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "This is a class variable\n"
     ]
    }
   ],
   "source": [
    "obj = className()\n",
    "print(obj.var)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "I am inside the class\n"
     ]
    }
   ],
   "source": [
    "obj.func()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "This is a class variable \n",
      " This is a updated variable\n"
     ]
    }
   ],
   "source": [
    "obj2 = className()\n",
    "obj2.var = \"This is a updated variable\"\n",
    "print(obj.var,\"\\n\",obj2.var)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [],
   "source": [
    "# __init__ method in python i.e constructor method"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [],
   "source": [
    "# object of class is constructed"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "metadata": {},
   "outputs": [],
   "source": [
    "class Student:\n",
    "    def __init__(self, name, branch, year):\n",
    "        self.n = name\n",
    "        self.b = branch\n",
    "        self.y = year\n",
    "    def print_method(self):\n",
    "        print(\"Name: \" + self.n)\n",
    "        print(\"Branch: \" + self.b)\n",
    "        print(\"year: \" + str(self.y))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "metadata": {},
   "outputs": [],
   "source": [
    "obj = Student(\"Karn\", \"EEE\", 2019)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Name: Karn\n",
      "Branch: EEE\n",
      "year: 2019\n"
     ]
    }
   ],
   "source": [
    "obj.print_method()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 12,
   "metadata": {},
   "outputs": [],
   "source": [
    "class Vehicle:\n",
    "    name = \"\"\n",
    "    kind = \"car\"\n",
    "    color = \"\"\n",
    "    value = 100.00\n",
    "    def description(self):\n",
    "        des_str = \"%s is a %s %s worth $%.2f.\" % (self.name, self.color, self.color, self.value)\n",
    "        return des_str"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 13,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Ferrari is a red red worth $70000.00.\n",
      "convertible is a blue blue worth $15000.00.\n"
     ]
    }
   ],
   "source": [
    "car1 = Vehicle()\n",
    "car2 = Vehicle()\n",
    "\n",
    "car1.name = \"Ferrari\"\n",
    "car2.name = \"convertible\"\n",
    "\n",
    "car1.color = \"red\"\n",
    "car1.value = 70000\n",
    "\n",
    "car2.color = \"blue\"\n",
    "car2.value = 15000\n",
    "\n",
    "print(car1.description())\n",
    "print(car2.description())"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 14,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Inheritance in Python\n",
    "# Inheritance allows us to define a class that inherits all the methods and properties from another class.\n",
    "# Parent class is the class being inherited from, also called base class.\n",
    "# Child class is the class that inherits from another class, also called derived class."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 15,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Single Inheritance\n",
    "class fruit:\n",
    "    def __init__(self):\n",
    "        print(\"I am a fruit\")\n",
    "class citrus(fruit):\n",
    "    def __init__(self):\n",
    "        super().__init__()\n",
    "        print(\"I am a citrus\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 16,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "I am a fruit\n",
      "I am a citrus\n"
     ]
    }
   ],
   "source": [
    "f = citrus()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 17,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "I am a fruit\n"
     ]
    }
   ],
   "source": [
    "f = fruit()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 18,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "True"
      ]
     },
     "execution_count": 18,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Multiple Inheritance\n",
    "# Pass : It is used when a statement is required syntactically but you do not want any command or code to execute.\n",
    "class A:\n",
    "    pass\n",
    "class B:\n",
    "    pass\n",
    "class C(A,B):\n",
    "    pass\n",
    "issubclass(C,B) and issubclass(C,A)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 19,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "1\n"
     ]
    }
   ],
   "source": [
    "# Multilevel Inheritance\n",
    "class A:\n",
    "    x = 1\n",
    "class B(A):\n",
    "    pass\n",
    "class C(B):\n",
    "    pass\n",
    "obj = C()\n",
    "print(obj.x)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 20,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "1\n",
      "1\n"
     ]
    },
    {
     "data": {
      "text/plain": [
       "True"
      ]
     },
     "execution_count": 20,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Hierarchical Inheritance\n",
    "class A:\n",
    "    x = 1\n",
    "class B(A):\n",
    "    pass\n",
    "class C(A):\n",
    "    pass\n",
    "\n",
    "obj = B()\n",
    "obj1 = C()\n",
    "\n",
    "print(obj.x)\n",
    "print(obj1.x)\n",
    "issubclass(C,A) and issubclass(B,A)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 21,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "1\n"
     ]
    }
   ],
   "source": [
    "# Hybrid Inheritance\n",
    "# Combination of two inheritance\n",
    "class A:\n",
    "    x = 1\n",
    "class B(A):\n",
    "    pass\n",
    "class C(A):\n",
    "    pass\n",
    "class D(C,B):\n",
    "    pass\n",
    "\n",
    "obj = D()\n",
    "print(obj.x)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 22,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Starting engine\n",
      "I have two wheel\n",
      "Stop engine\n"
     ]
    }
   ],
   "source": [
    "# Inheritance Super Function\n",
    "class Vehicle:\n",
    "    def start(self):\n",
    "        print(\"Starting engine\")\n",
    "    def stop(self):\n",
    "        print(\"Stop engine\")\n",
    "class TwoWheeler(Vehicle):\n",
    "    def say(self):\n",
    "        super().start()\n",
    "        print(\"I have two wheel\")\n",
    "        super().stop()\n",
    "\n",
    "Harley = TwoWheeler()\n",
    "Harley.say()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 23,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Overriding and Overloading\n",
    "# Overloading example\n",
    "def add(a,b):\n",
    "    return a + b\n",
    "\n",
    "def add(a,b,c):\n",
    "    return a + b + c"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 24,
   "metadata": {},
   "outputs": [
    {
     "ename": "TypeError",
     "evalue": "add() missing 1 required positional argument: 'c'",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mTypeError\u001b[0m                                 Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-24-60bc6df41bcf>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[1;32m----> 1\u001b[1;33m \u001b[0madd\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;36m2\u001b[0m\u001b[1;33m,\u001b[0m\u001b[1;36m4\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[1;31mTypeError\u001b[0m: add() missing 1 required positional argument: 'c'"
     ]
    }
   ],
   "source": [
    "add(2,4)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 25,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "6"
      ]
     },
     "execution_count": 25,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "def add(a,b,c):\n",
    "    return a + b + c\n",
    "\n",
    "def add(a,b):\n",
    "    return a + b\n",
    "\n",
    "add(2,4)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 26,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Overloading a function\n",
    "def add(instanceOf, *args):\n",
    "    if instanceOf == 'int':\n",
    "        result = 0\n",
    "    if instanceOf == 'str':\n",
    "        result = ''\n",
    "    if instanceOf == 'float':\n",
    "        result = 0.0  \n",
    "    for i in args:\n",
    "        result += i\n",
    "    return result\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 27,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "6"
      ]
     },
     "execution_count": 27,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "add('int',1,2,3)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 28,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Overiding a function\n",
    "# subclass is changing the functionality of parent class function\n",
    "class A:\n",
    "    def sayhi(self):\n",
    "        print('I am in A')\n",
    "class B(A):\n",
    "    def sayhi(self):\n",
    "        print('I am in B')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 29,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "I am in A\n"
     ]
    }
   ],
   "source": [
    "obj = A()\n",
    "obj.sayhi()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 30,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "I am in B\n"
     ]
    }
   ],
   "source": [
    "obj = B()\n",
    "obj.sayhi()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 31,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Encapsulation\n",
    "# Abstraction + data hiding"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 36,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "123\n",
      "123\n"
     ]
    },
    {
     "ename": "AttributeError",
     "evalue": "'Encap' object has no attribute '__c'",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mAttributeError\u001b[0m                            Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-36-a577cc197851>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[0;32m      8\u001b[0m \u001b[0mprint\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mobj\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0ma\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m      9\u001b[0m \u001b[0mprint\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mobj\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0m_b\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m---> 10\u001b[1;33m \u001b[0mprint\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mobj\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0m__c\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[1;31mAttributeError\u001b[0m: 'Encap' object has no attribute '__c'"
     ]
    }
   ],
   "source": [
    "class Encap:\n",
    "    def __init__(self):\n",
    "        self.a = 123\n",
    "        self._b = 123\n",
    "        self.__c = 123 # cannot be access by the object\n",
    "\n",
    "obj = Encap()\n",
    "print(obj.a)\n",
    "print(obj._b)\n",
    "print(obj.__c)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 37,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "123\n",
      "123\n",
      "123\n"
     ]
    }
   ],
   "source": [
    "class Encap:\n",
    "    def __init__(self):\n",
    "        self.a = 123\n",
    "        self.b = 123\n",
    "        self.c = 123\n",
    "\n",
    "obj = Encap()\n",
    "print(obj.a)\n",
    "print(obj.b)\n",
    "print(obj.c)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 38,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Updating Software\n",
      "Driving\n"
     ]
    }
   ],
   "source": [
    "# Private Method\n",
    "class car:\n",
    "    def __init__(self):\n",
    "        self.__updateSoftware()\n",
    "    def drive(self):\n",
    "        print(\"Driving\")\n",
    "    def __updateSoftware(self):\n",
    "        print('Updating Software')\n",
    "\n",
    "redcar = car()\n",
    "redcar.drive()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 39,
   "metadata": {},
   "outputs": [
    {
     "ename": "AttributeError",
     "evalue": "'car' object has no attribute '__updateSoftware'",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mAttributeError\u001b[0m                            Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-39-e237882c312a>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[1;32m----> 1\u001b[1;33m \u001b[0mredcar\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0m__updateSoftware\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[1;31mAttributeError\u001b[0m: 'car' object has no attribute '__updateSoftware'"
     ]
    }
   ],
   "source": [
    "redcar.__updateSoftware()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 40,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "123\n",
      "123\n",
      "123\n"
     ]
    }
   ],
   "source": [
    "class Encap:\n",
    "    def __init__(self):\n",
    "        self.a = 123\n",
    "        self._b = 123\n",
    "        self.__c = 123 # cannot be access by the object\n",
    "\n",
    "obj = Encap()\n",
    "print(obj.a)\n",
    "print(obj._b)\n",
    "print(obj._Encap__c)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 41,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Updating Software\n"
     ]
    }
   ],
   "source": [
    "redcar._car__updateSoftware()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 63,
   "metadata": {},
   "outputs": [
    {
     "ename": "AttributeError",
     "evalue": "'car' object has no attribute '__speed'",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mAttributeError\u001b[0m                            Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-63-2b077c2a1ada>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[0;32m      7\u001b[0m \u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m      8\u001b[0m \u001b[0mobj\u001b[0m \u001b[1;33m=\u001b[0m \u001b[0mcar\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m----> 9\u001b[1;33m \u001b[0mprint\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mobj\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0m__speed\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[1;31mAttributeError\u001b[0m: 'car' object has no attribute '__speed'"
     ]
    }
   ],
   "source": [
    "# Private variable\n",
    "class car:\n",
    "    __speed = 10\n",
    "    \n",
    "    def __init__(self):\n",
    "        self.__speed = 10\n",
    "\n",
    "obj = car()\n",
    "print(obj.__speed)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 64,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "10\n"
     ]
    }
   ],
   "source": [
    "print(obj._car__speed)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 65,
   "metadata": {},
   "outputs": [],
   "source": [
    "obj.__speed = 20"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 66,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "20"
      ]
     },
     "execution_count": 66,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "obj.__speed"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 67,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Polymorphism\n",
    "class Shark:\n",
    "    def swim(self):\n",
    "        print(\"The shark is swimming\")\n",
    "    def skeleton(self):\n",
    "        print(\"The shark skeleton is made of cartilage\")\n",
    "\n",
    "class Clownfish:\n",
    "    def swim(self):\n",
    "        print(\"The clownfish is swimming\")\n",
    "    def skeleton(self):\n",
    "        print(\"The clownfish skeleton is made of bone\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 68,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "The shark is swimming\n",
      "The clownfish is swimming\n"
     ]
    }
   ],
   "source": [
    "obj = Shark()\n",
    "obj1 = Clownfish()\n",
    "\n",
    "obj.swim()\n",
    "obj1.swim()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 69,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "The shark skeleton is made of cartilage\n",
      "The clownfish skeleton is made of bone\n"
     ]
    }
   ],
   "source": [
    "obj.skeleton()\n",
    "obj1.skeleton()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
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