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"worksheets": [
{
"cells": [
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h1>Chapter 14: Inheritance<h1>"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 14.1, Page Number: 333<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"\n",
"class road_vehicle:\n",
" def __init__(self):\n",
" self.__wheels=None\n",
" self.__passengers=None\n",
" def set_wheels(self,num):\n",
" self.__wheels=num\n",
" def get_wheels(self):\n",
" return self.__wheels\n",
" def set_pass(self,num):\n",
" self.__passengers=num\n",
" def get_pass(self):\n",
" return self.__passengers\n",
"\n",
"#Define a truck\n",
"class truck(road_vehicle):\n",
" def __init__(self):\n",
" self.__cargo=None\n",
" def set_cargo(self,size):\n",
" self.__cargo=size\n",
" def get_cargo(self):\n",
" return self.__cargo\n",
" def show(self):\n",
" print \"wheels: \",self.get_wheels()\n",
" print \"passengers: \",self.get_pass()\n",
" print \"cargo capacity in cubic feet: \",self.__cargo\n",
" \n",
"#Define an enum type\n",
"(car,van,wagon)=(1,2,3)\n",
"type=[\"car\",\"van\",\"wagon\"]\n",
" \n",
"#Define an automobile\n",
"class automobile(road_vehicle):\n",
" def __init__(self):\n",
" self.car_type=None\n",
" def set_type(self,t):\n",
" self.car_type=t\n",
" def get_type(self):\n",
" return self.car_type\n",
" def show(self):\n",
" print \"wheels: \",self.get_wheels()\n",
" print \"passengers: \",self.get_pass()\n",
" print \"type: \",\n",
" if self.get_type()==1:\n",
" print \"car\"\n",
" elif self.get_type()==2:\n",
" print \"van\"\n",
" elif self.get_type()==3:\n",
" print \"wagon\"\n",
" \n",
"#Variable declaration\n",
"t1=truck()\n",
"t2=truck()\n",
"c=automobile()\n",
"\n",
"t1.set_wheels(18)\n",
"t1.set_pass(2)\n",
"t1.set_cargo(3200)\n",
"\n",
"t2.set_wheels(6)\n",
"t2.set_pass(3)\n",
"t2.set_cargo(1200)\n",
"\n",
"t1.show()\n",
"t2.show()\n",
"\n",
"c.set_wheels(4)\n",
"c.set_pass(6)\n",
"c.set_type(van)\n",
"\n",
"c.show() \n",
" "
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"wheels: 18\n",
"passengers: 2\n",
"cargo capacity in cubic feet: 3200\n",
"wheels: 6\n",
"passengers: 3\n",
"cargo capacity in cubic feet: 1200\n",
"wheels: 4\n",
"passengers: 6\n",
"type: van\n"
]
}
],
"prompt_number": 1
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 14.2, Page Number: 335<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"\n",
"class base:\n",
" def __init__(self):\n",
" self.__i=self.__j=None\n",
" def set(self,a,b):\n",
" self.__i=a\n",
" self.__j=b\n",
" def show(self):\n",
" print self.__i,self.__j\n",
" \n",
"class derived(base):\n",
" def __init__(self,x):\n",
" self.__k=x\n",
" def showk(self):\n",
" print self.__k\n",
" \n",
"#Variable declaration\n",
"ob = derived(3)\n",
"\n",
"ob.set(1,2) #access member of base\n",
"ob.show() #access member of base\n",
"\n",
"ob.showk() #uses member of derived class\n",
" "
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"1 2\n",
"3\n"
]
}
],
"prompt_number": 1
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 14.3, Page Number: 337<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"class base:\n",
" def __init__(self):\n",
" self.__i=self.__j=None #These act as protected members\n",
" def set(self,a,b):\n",
" self.__i=a\n",
" self.__j=b\n",
" def show(self):\n",
" print self.__i,self.__j\n",
" \n",
"class derived(base):\n",
" def __init__(self):\n",
" self.__k=None\n",
" def setk(self):\n",
" self.__k=self._base__i*self._base__j #accessing private variables in derived class\n",
" def showk(self):\n",
" print self.__k\n",
" \n",
"#Variable declaration\n",
"ob = derived()\n",
"\n",
"ob.set(2,3) #OK, known to be derived\n",
"ob.show() #OK, known to be derived\n",
"\n",
"ob.setk()\n",
"ob.showk() #uses member of derived class\n",
" "
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"2 3\n",
"6\n"
]
}
],
"prompt_number": 10
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 14.4, Page Number: 338<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"\n",
"class base:\n",
" def __init__(self):\n",
" self.__i=None\n",
" self.__j=None\n",
" def set(self,a,b):\n",
" self.__i=a\n",
" self.__j=b\n",
" def show(self):\n",
" print self.__i,self.__j\n",
" \n",
"class derived1(base):\n",
" def __init__(self):\n",
" self.__k=None\n",
" def setk(self):\n",
" self.__k=self._base__i*self._base__j\n",
" def showk(self):\n",
" print self.__k\n",
"\n",
"class derived2(derived1):\n",
" def __init__(self):\n",
" self.__m=None\n",
" def setm(self):\n",
" self.__m=self._base__i-self._base__j\n",
" def showm(self):\n",
" print self.__m\n",
" \n",
" \n",
"#Variable declaration\n",
"ob1 = derived1()\n",
"ob2 = derived2()\n",
"\n",
"ob1.set(2,3) #access member of base\n",
"ob1.show() #access member of base\n",
"ob1.setk() #uses member of derived1 class\n",
"ob1.showk() #uses member of derived1 class\n",
"\n",
"ob2.set(3,4) #access member of base\n",
"ob2.show() #access member of base\n",
"ob2.setk() #access member of derived1 class\n",
"ob2.setm() #access member of derived2 class\n",
"ob2.showk() #uses member of derived1 class\n",
"ob2.showm() #uses member of derived1 class\n",
" "
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"2 3\n",
"6\n",
"3 4\n",
"12\n",
"-1\n"
]
}
],
"prompt_number": 11
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 14.5, Page Number: 341<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"\n",
"class base:\n",
" def __init__(self):\n",
" self.__i=None\n",
" self._j=None\n",
" self.k=None\n",
" def seti(self,a):\n",
" self.__i=a\n",
" def geti(self):\n",
" return i\n",
" \n",
"class derived(base):\n",
" def setj(self,a):\n",
" self._j=a\n",
" def setk(self,a):\n",
" self.k=a\n",
" def getj(self):\n",
" return self._j\n",
" def getk(self):\n",
" return self.k\n",
" \n",
"#Variable declaration \n",
"ob=derived()\n",
"\n",
"ob.setk(10)\n",
"print ob.getk(),\n",
"ob.setj(12)\n",
"print ob.getj()"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"10 12\n"
]
}
],
"prompt_number": 1
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 14.6, Page Number: 342<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"\n",
"class base1:\n",
" def __init__(self):\n",
" self.x=None\n",
" def showx(self):\n",
" print self.x\n",
" \n",
"class base2:\n",
" def __init__(self):\n",
" self.y=None\n",
" def showy(self):\n",
" print self.y\n",
" \n",
"class derived(base1,base2):\n",
" def set(self,i,j):\n",
" self.x=i\n",
" self.y=j\n",
" \n",
"#Variable declaration\n",
"ob = derived()\n",
"\n",
"ob.set(10,20) #provided by derived\n",
"ob.showx() #from base1\n",
"ob.showy() #from base2\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"10\n",
"20\n"
]
}
],
"prompt_number": 17
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 14.7, Page Number: 343<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"\n",
"class base:\n",
" def __init__(self):\n",
" print \"Constructing base\"\n",
" def __del__(self):\n",
" print \"Destructing base\"\n",
"\n",
"class derived(base):\n",
" def __init__(self):\n",
" base.__init__(self)\n",
" print \"Constructing derived\"\n",
" def __del__(self):\n",
" print \"Destructing derived\"\n",
" for b in self.__class__.__bases__:\n",
" b.__del__(self)\n",
"\n",
"#Variable declaration\n",
"ob=derived()\n",
"\n",
"#Does nothing but construct and destruct ob"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Constructing base\n",
"Constructing derived\n",
"Destructing derived\n",
"Destructing base\n"
]
}
],
"prompt_number": 19
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 14.8, Page Number: 344<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"class base:\n",
" def __init__(self):\n",
" print \"Constructing base\"\n",
" def __del__(self):\n",
" print \"Destructing base\"\n",
"\n",
"class derived1(base):\n",
" def __init__(self):\n",
" base.__init__(self)\n",
" print \"Constructing derived1\"\n",
" def __del__(self):\n",
" print \"Destructing derived1\"\n",
" super(derived1,self).__del__(self)\n",
"\n",
"class derived2(derived1):\n",
" def __init__(self):\n",
" derived1.__init__(self)\n",
" print \"Constructing derived2\"\n",
" def __del__(self):\n",
" print \"Destructing derived2\"\n",
" super(self.__class__,self).__del__(self)\n",
" \n",
"#Variable declaration\n",
"ob=derived2()\n",
"\n",
"#Does nothing but construct and destruct ob"
],
"language": "python",
"metadata": {},
"outputs": []
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 14.9, Page Number: 345<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"class base1:\n",
" def __init__(self):\n",
" print \"Constructing base1\"\n",
" def __del__(self):\n",
" print \"Destructing base1\"\n",
" \n",
"class base2:\n",
" def __init__(self):\n",
" print \"Constructing base2\"\n",
" def __del__(self):\n",
" print \"Destructing base2\"\n",
" \n",
"class derived(base1,base2):\n",
" def __init__(self):\n",
" for b in self.__class__.__bases__:\n",
" b.__init__(self)\n",
" print \"Constructing derived\"\n",
" def __del__(self):\n",
" print \"Destructing derived\"\n",
" for b in self.__class__.__bases__:\n",
" b.__del__(self)\n",
" \n",
"#Variable declaration\n",
"ob = derived()\n",
"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Constructing base1\n",
"Constructing base2\n",
"Constructing derived\n",
"Destructing derived\n",
"Destructing base1\n",
"Destructing base2\n"
]
}
],
"prompt_number": 21
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 14.10, Page Number: 347<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"class base:\n",
" def __init__(self,x):\n",
" self._i=x\n",
" print \"Constructing base\"\n",
" def __del__(self):\n",
" print \"Destructing base\"\n",
"\n",
"class derived(base):\n",
" def __init__(self,x,y):\n",
" base.__init__(self,y)\n",
" self.__j=x\n",
" print \"Constructing derived\"\n",
" def __del__(self):\n",
" print \"Destructing derived\"\n",
" for b in self.__class__.__bases__:\n",
" b.__del__(self)\n",
" def show(self):\n",
" print self._i,self.__j\n",
"\n",
"#Variable declaration\n",
"ob=derived(3,4)\n",
"\n",
"#Result\n",
"ob.show() #shows 4 3"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Constructing base\n",
"Constructing derived\n",
"Destructing derived\n",
"Destructing base\n",
"4 3\n"
]
}
],
"prompt_number": 23
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 14.11, Page Number: 348<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"class base1:\n",
" def __init__(self,x):\n",
" self._i=x\n",
" print \"Constructing base1\"\n",
" def __del__(self):\n",
" print \"Destructing base1\"\n",
" \n",
"class base2:\n",
" def __init__(self,x):\n",
" self._k=x\n",
" print \"Constructing base2\"\n",
" def __del__(self):\n",
" print \"Destructing base2\"\n",
" \n",
"class derived(base1,base2):\n",
" def __init__(self,x,y,z):\n",
" self.__j=x\n",
" i=0\n",
" for b in self.__class__.__bases__:\n",
" if i==0:\n",
" b.__init__(self,y)\n",
" else :\n",
" b.__init__(self,z)\n",
" i+=1\n",
" print \"Constructing derived\"\n",
" def __del__(self):\n",
" print \"Destructing derived\"\n",
" for b in self.__class__.__bases__:\n",
" b.__del__(self)\n",
" def show(self):\n",
" print self._i,self.__j,self._k\n",
" \n",
"#Variable declaration\n",
"ob = derived(3,4,5)\n",
"\n",
"#Result\n",
"ob.show()\n",
"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Constructing base1\n",
"Constructing base2\n",
"Constructing derived\n",
"Destructing derived\n",
"Destructing base1\n",
"Destructing base2\n",
"4 3 5\n"
]
}
],
"prompt_number": 25
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 14.12, Page Number: 348<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"class base1:\n",
" def __init__(self,x):\n",
" self._i=x\n",
" print \"Constructing base1\"\n",
" def __del__(self):\n",
" print \"Destructing base1\"\n",
" \n",
"class base2:\n",
" def __init__(self,x):\n",
" self._k=x\n",
" print \"Constructing base2\"\n",
" def __del__(self):\n",
" print \"Destructing base2\"\n",
" \n",
"class derived(base1,base2):\n",
" def __init__(self,x,y):\n",
" i=0\n",
" for b in self.__class__.__bases__:\n",
" if i==0:\n",
" b.__init__(self,x)\n",
" else :\n",
" b.__init__(self,y)\n",
" i+=1\n",
" print \"Constructing derived\"\n",
" def __del__(self):\n",
" print \"Destructing derived\"\n",
" for b in self.__class__.__bases__:\n",
" b.__del__(self)\n",
" def show(self):\n",
" print self._i,self._k\n",
" \n",
"#Variable declaration\n",
"ob = derived(3,4)\n",
"\n",
"#Result\n",
"ob.show()\n",
"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Constructing base1\n",
"Constructing base2\n",
"Constructing derived\n",
"Destructing derived\n",
"Destructing base1\n",
"Destructing base2\n",
"3 4\n"
]
}
],
"prompt_number": 26
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 14.13, Page Number: 351<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"class base:\n",
" def __init__(self):\n",
" self.__i=None\n",
" self.j=self.k=None\n",
" def seti(self,x):\n",
" self.__i=x\n",
" def geti(self):\n",
" return self.__i\n",
"\n",
"class derived(base):\n",
" def __init__(self):\n",
" self.a=None\n",
"\n",
"\n",
"#Variable declaration\n",
"ob=derived()\n",
"\n",
"ob._base__i=10 #Accessing private members of base class\n",
"ob.j=20 #legal because j and k are public variable in base\n",
"ob.k=30\n",
"\n",
"ob.a=40 #legal because a is public in derived class\n",
"ob.seti(10)\n",
"\n",
"#Result\n",
"print ob.geti(),ob.j,ob.a"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"10 20 40\n"
]
}
],
"prompt_number": 28
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 14.14, Page Number: 354<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"class base:\n",
" def __init__(self):\n",
" self.i=None\n",
"\n",
"#derived1 inherits base\n",
"class derived1(base):\n",
" def __init__(self):\n",
" self.__j=None\n",
" \n",
"#derived2 inherits base\n",
"class derived2(base):\n",
" def __init__(self):\n",
" self.__k=None\n",
"\n",
"#derived3 inherits from both derived1 and derived2\n",
"class derived3(derived1,derived2):\n",
" def __init__(self):\n",
" self.__sum=None\n",
" \n",
"#Variable declaration\n",
"ob=derived3()\n",
"\n",
"ob.i=10\n",
"ob.j=20\n",
"ob.k=30\n",
"\n",
"ob.sum=ob.i+ob.j+ob.k\n",
"\n",
"#Result\n",
"print ob.i,ob.j,ob.k,ob.sum"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"10 20 30 60\n"
]
}
],
"prompt_number": 29
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<h3>Example 14.15, Page Number: 355<h3>"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"class base:\n",
" def __init__(self):\n",
" self.i=None\n",
"\n",
"#derived1 inherits base\n",
"class derived1(base):\n",
" def __init__(self):\n",
" self.__j=None\n",
" \n",
"#derived2 inherits base\n",
"class derived2(base):\n",
" def __init__(self):\n",
" self.__k=None\n",
"\n",
"#derived3 inherits from both derived1 and derived2\n",
"class derived3(derived1,derived2):\n",
" def __init__(self):\n",
" self.__sum=None\n",
" \n",
"#Variable declaration\n",
"ob=derived3()\n",
"\n",
"ob.i=10\n",
"ob.j=20\n",
"ob.k=30\n",
"\n",
"ob.sum=ob.i+ob.j+ob.k\n",
"\n",
"#Result\n",
"print ob.i,ob.j,ob.k,ob.sum"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"10 20 30 60\n"
]
}
],
"prompt_number": 30
},
{
"cell_type": "code",
"collapsed": false,
"input": [],
"language": "python",
"metadata": {},
"outputs": []
}
],
"metadata": {}
}
]
}