Chereads / PYTHON / Chapter 3 - .py final

Chapter 3 - .py final

Q1. Attempt any FIVE of the following. (10 Marks)

a) Name different modes of Python.

> We can develop a python program in 2 different styles.

😇Interactive Mode and

😈Batch Mode./script

😇interactive :

-Interactive mode is a command line shell.

-Typically the interactive mode is used to test the features of the python, or to run a smaller script

that may not be reusable.

-The >>> indicates that the Python shell is ready to execute and send your commands to the

Python interpreter.

-The result is immediately displayed on the Python shell as soon as the Python

interpreter interprets the command.

-To run your Python statements, just type them and hit the enter key. You will get the results

immediately, unlike in script mode. For example, to print the text "Hello World", we can type the

following:

>>> print("Hello World")

Hello World

>>>

😈Script :

-If you need to write a long piece of Python code or your Python script spans multiple files,

interactive mode is not recommended.

-Script mode is the way to go in such cases.

-In script mode,

You write your code in a text file then save it with a .py extension which stands for "Python".

-Note

that you can use any text editor for this, including Sublime, Atom, notepad++, etc.

b) List identity operators.

>

Identity operators compare the memory locations of two objects. There are two Identity

operators as explained below −

Operator Description

Example

is

Evaluates to true if the variables on either

side of the operator point to the same object

and false otherwise.

x is y, here is results in 1 if id(x) equals

id(y).

is not

Evaluates to false if the variables on either

side of the operator point to the same object

and true otherwise.

x is not y, here is not results in 1 if id(x) is

not equal to id(y).

c) Describe Dictionary.

Answer: Dictionary in Python is an unordered collection of data values, used to store data values

like a map,

In Python, a Dictionary can be created by placing sequence of elements within curly {} braces,

separated by 'comma'. Dictionary holds a pair of values, one being the Key and the other

corresponding pair element being its Key:value. Values in a dictionary can be of any datatype and

can be duplicated, whereas keys can't be repeated and must be immutable.

Dict = {1: 'Geeks', 2: 'For', 3: 'Geeks'}

print("\nDictionary with the use of Integer Keys: ")

print(Dict)

d) State use of namespace in Python.

Answer: A namespace is a simple system to control the names in a program. It ensures that names

are unique and won't lead to any conflict.

Python implements namespaces in the form of dictionaries. It maintains a name-to-object mapping

where names act as keys and the objects as values. Multiple namespaces may have the same name

but pointing to a different variable..

ï‚· Local Namespace

This namespace covers the local names inside a function. Python creates this namespace

for every function called in a program. It remains active until the function returns.

ï‚· Global Namespace

This namespace covers the names from various imported modules used in a project. Python

creates this namespace for every module included in your program. It'll last until the

program ends.

ï‚· Built-in Namespace

This namespace covers the built-in functions and built-in exception names. Python creates

it as the interpreter starts and keeps it until you exit.

e) List different Object Oriented features supported by Python.

Answer: Python is also an object-oriented language since its beginning. Python is an objectoriented programming language. It allows us to develop applications using an Object Oriented

approach. In Python, we can easily create and use classes and objects.

Major principles of object-oriented programming system are given below.

ï‚· Object

ï‚· Class

ï‚· Method

ï‚· Inheritance

ï‚· Polymorphism

ï‚· Data Abstraction

ï‚· Encapsulation

g) Describe Python Interpreter.

Answer: An interpreter is a program that reads and executes code. This includes source code, precompiled code, and scripts. Common interpreters include Perl, Python, and Ruby interpreters,

which execute Perl, Python, and Ruby code respectively.

The Python interpreter is the application that runs your python script. Read the script line by line

and converts that script into python byte code, and then writes the byte code into a pyc file. If your

application has multiple files it creates a pyc file for every .py file. It is at this stage that syntax

errors are generated.

Q.2) Attempt any THREE of the following.

(12 Marks)

a) Explain two Membership and two logical operators in python with appropriate examples.

Answer: Python's membership operators test for membership in a sequence, such as strings, lists,

or tuples. There are two membership operators as explained below −

Operator Description

Example

in

Evaluates to true if it finds a variable in the

specified sequence and false otherwise.

x in y, here in results in a 1 if x is a member

of sequence y.

not in

Evaluates to true if it does not finds a

variable in the specified sequence and false

otherwise.

x not in y, here not in results in a 1 if x is

not a member of sequence y.

Example

#!/usr/bin/python

a = 10

b = 20

list = [1, 2, 3, 4, 5 ];

if ( a in list ):

print "Line 1 - a is available in the given list"

else:

print "Line 1 - a is not available in the given list"

if ( b not in list ):

print "Line 2 - b is not available in the given list"

else:

print "Line 2 - b is available in the given list"

a = 2

if ( a in list ):

print "Line 3 - a is available in the given list"

else:

print "Line 3 - a is not available in the given list"

When you execute the above program it produces the following result −

Line 1 - a is not available in the given list

Line 2 - b is not available in the given list

Line 3 - a is available in the given list

There are following logical operators supported by Python language. Assume variable a holds 10

and variable b holds 20 then −

Operator Description

Example

and

Logical

AND

If both the operands are true then condition

becomes true.

(a and b) is true.

or

Logical

OR

If any of the two operands are non-zero

then condition becomes true.

(a or b) is true.

not

Logical

NOT

Used to reverse the logical state of its

operand.

Not(a and b) is false.

b) Describe any four methods of lists in Python.

Answer: The list is a most versatile datatype available in Python which can be written as a list of

comma-separated values (items) between square brackets. Important thing about a list is that items

in a list need not be of the same type.

Creating a list is as simple as putting different comma-separated values between square brackets.

For example −

list1 = ['physics', 'chemistry', 1997, 2000];

list2 = [1, 2, 3, 4, 5 ];

list3 = ["a", "b", "c", "d"]

The methods of list are as follows -:

1. cmp(list1,list2) -: Comapre elements of both lists

Syntax

cmp(list1, list2)

Parameters

 list1 − This is the first list to be compared.

 list2 − This is the second list to be compared.

list1, list2 = [123, 'xyz'], [456, 'abc']

print cmp(list1, list2)

print cmp(list2, list1)

list3 = list2 + [786];

print cmp(list2, list3)

When we run above program, it produces following result −

-1

1

-1

2. Python list method len() returns the number of elements in the list.

Syntax len(list)

Parameters

 list − This is a list for which number of elements to be counted.

Example

#!/usr/bin/python

list1, list2 = [123, 'xyz', 'zara'], [456, 'abc']

print "First list length : ", len(list1)

print "Second list length : ", len(list2)

When we run above program, it produces following result −

First list length : 3

Second list length : 2

3. Python list method max returns the elements from the list with maximum value.

Syntax

max(list)

Parameters

 list − This is a list from which max valued element to be returned.

Example

#!/usr/bin/python

list1, list2 = [123, 'xyz', 'zara', 'abc'], [456, 700, 200]

print "Max value element : ", max(list1)

print "Max value element : ", max(list2)

When we run above program, it produces following result −

Max value element : zara

Max value element : 700

c) Comparing between local and global variable.

Answer:

local 😇&global😈 variable

😇declared inside function

😈declared outside function

😇accessible only😈😇😈😇😈😇😈😇😈😇😈

d) Write a python program to print Fibonacci series up to n terms.

Answer:

nterms = int(input("How many terms? "))

# first two terms

n1, n2 = 0, 1

count = 0

# check if the number of terms is valid

if nterms <= 0:

print("Please enter a positive integer")

elif nterms == 1:

print("Fibonacci sequence upto",nterms,":")

print(n1)

else:

print("Fibonacci sequence:")

while count < nterms:

print(n1)

nth = n1 + n2

# update values

n1 = n2

n2 = nth

count += 1

Q.3) Attempt any THREE of the following.

(12 Marks)

a) Write a program to input any two tuples and interchange the tuple variable.

Answer:

t1 = tuple( )

n = input("Total number of values m first tuple")

for i in range (n):

a = input("Enter elements")

t2 = t2 + (a, )

print "First tuple"

print t1

print "Second tuple"

print t2 t1, t2 = t2, t1

print "After swapping"

print "First tuple"

print t1

print "Second tuple"

print t2

b) Explain different loops available in python with suitable examples.

Answer: In general, statements are executed sequentially: The first statement in a function is

executed first, followed by the second, and so on. There may be a situation when you need to

execute a block of code several number of times.

Programming languages provide various control structures that allow for more complicated

execution paths.

A loop statement allows us to execute a statement or group of statements multiple times. The

following diagram illustrates a loop statement –

DIAGRAM 1

1. While Loop

A while loop statement in Python programming language repeatedly executes a target statement

as long as a given condition is true.

Syntax

The syntax of a while loop in Python programming language is −

while expression:

statement(s)

DIAGRAM2

Example

count = 0

while (count < 9):

print 'The count is:', count

count = count + 1

print "Good bye!"

2. For Loop

It has the ability to iterate over the items of any sequence, such as a list or a string.

Syntax

for iterating_var in sequence:

statements(s)

If a sequence contains an expression list, it is evaluated first. Then, the first item in the sequence

is assigned to the iterating variable iterating_var. Next, the statements block is executed. Each item

in the list is assigned to iterating_var, and the statement(s) block is executed until the entire

sequence is exhausted.

Flow Diagram

DIAGRAM 3

Example

#!/usr/bin/python

for letter in 'Python': # First Example

print 'Current Letter :', letter

fruits = ['banana', 'apple', 'mango']

for fruit in fruits: # Second Example

print 'Current fruit :', fruit

print "Good bye!"

3. Nested Loops

Python programming language allows to use one loop inside another loop. Following section

shows few examples to illustrate the concept.

Syntax

for iterating_var in sequence:

for iterating_var in sequence:

statements(s)

statements(s)

The syntax for a nested while loop statement in Python programming language is as follows –

while expression:

while expression:

statement(s)

statement(s)

Example

The following program uses a nested for loop to find the prime numbers from 2 to 100 –

#!/usr/bin/python

i = 2

while(i < 100):

j = 2

while(j <= (i/j)):

if not(i%j): break

j = j + 1

if (j > i/j) : print i, " is prime"

i = i + 1

print "Good bye!"

d) Illustrate the use of method overriding? Explain with example.

Answer: Method overriding is an ability of any object-oriented programming language that allows

a subclass or child class to provide a specific implementation of a method that is already provided

by one of its super-classes or parent classes. When a method in a subclass has the same name,

same parameters or signature and same return type (or sub-type) as a method in its super-class,

then the method in the subclass is said to override the method in the super-class.

DIAGRAM 4

Example -:

# Python program to demonstrate

# method overriding

# Defining parent class

class Parent():

# Constructor

def __init__(self):

self.value = "Inside Parent"

# Parent's show method

def show(self):

print(self.value)

# Defining child class

class Child(Parent):

# Constructor

def __init__(self):

self.value = "Inside Child"

# Child's show method

def show(self):

print(self.value)

# Driver's code

obj1 = Parent()

obj2 = Child()

obj1.show()

obj2.show()

Output:

Inside Parent

Inside Child

Q.4) Attempt any THREE of the following.

(12 Marks)

a) Use of any four methods of tuple in python?

Answer: A tuple is a sequence of immutable Python objects. Tuples are sequences, just like lists.

The differences between tuples and lists are, the tuples cannot be changed unlike lists and tuples

use parentheses, whereas lists use square brackets.

1. LEN() Function -:

Python tuple method len() returns the number of elements in the tuple.

Syntax

len(tuple)

Example -:

tuple1, tuple2 = (123, 'xyz', 'zara'), (456, 'abc')

print "First tuple length : ", len(tuple1)

print "Second tuple length : ", len(tuple2)

2. MAX() Function -:

Python tuple method max() returns the elements from the tuple with maximum value.

Syntax

max(tuple)

Example -:

tuple1, tuple2 = (123, 'xyz', 'zara', 'abc'), (456, 700, 200)

print "Max value element : ", max(tuple1)

print "Max value element : ", max(tuple2)

3. MIN() Function -:

Python tuple method min() returns the elements from the tuple with minimum value.

Syntax

min(tuple)

Example -:

tuple1, tuple2 = (123, 'xyz', 'zara', 'abc'), (456, 700, 200)

print "min value element : ", min(tuple1)

print "min value element : ", min(tuple2)

4. CMP() Function -:

Python tuple method cmp() compares elements of two tuples.

Syntax

cmp(tuple1, tuple2)

Example -:

tuple1, tuple2 = (123, 'xyz'), (456, 'abc')

print cmp(tuple1, tuple2)

print cmp(tuple2, tuple1)

tuple3 = tuple2 + (786,);

print cmp(tuple2, tuple3)

b) Write a python program to read contents of first.txt file and write same content in

second.txt file.

with open("test.txt") as f:

with open("out.txt", "w") as f1:

for line in f:

f1.write(line)

c) Show how try…except blocks is used for exception handling in Python with example

Answer: The try block lets you test a block of code for errors. The except block lets you handle

the error.

When an error occurs, or exception as we call it, Python will normally stop and generate an error

message. These exceptions can be handled using the try statement:

How try() works?

ï‚· First try clause is executed i.e. the code between try and except clause.

ï‚· If there is no exception, then only try clause will run, except clause is finished.

ï‚· If any exception occured, try clause will be skipped and except clause will run.

ï‚· If any exception occurs, but the except clause within the code doesn't handle it, it is passed

on to the outer try statements. If the exception left unhandled, then the execution stops.

ï‚· A try statement can have more than one except clause.

try:

print(x)

except NameError:

print("Variable x is not defined")

except:

print("Something else went wrong")

Another Example -:

def divide(x, y):

try:

# Floor Division : Gives only Fractional Part as Answer

result = x // y

print("Yeah ! Your answer is :", result)

except ZeroDivisionError:

print("Sorry ! You are dividing by zero ")

d) Write the output for the following if the variable fruit='banana':

>>>fruit[:3]

>>>fruit[3:]

>>>fruit[3:3]

>>>fruit[:]

Answer: The output for the following code are as follows -:

>>>fruit[:3]

ban

>>>fruit[3:]

ana

>>>fruit[3:3]

n

>>>fruit[:]

banana

Q.5) Attempt any TWO of the following.

(12 Marks)

a) Determine various data types available in Python with example.

Answer: A variable can hold different types of values. For example, a person's name must be stored

as a string whereas its id must be stored as an integer.

Python provides various standard data types that define the storage method on each of them. The

data types defined in Python are given below.

1. Number

2. String

3. List

4. Tuple

5. Dictionary

Numbers

Number stores numeric values. Python creates Number objects when a number is assigned to a

variable. For example;

a = 3 , b = 5 #a and b are number objects

Python supports 4 types of numeric data.

int (signed integers like 10, 2, 29, etc.)

long (long integers used for a higher range of values like 908090800L, -0x1929292L, etc.)

float (float is used to store floating point numbers like 1.9, 9.902, 15.2, etc.)

complex (complex numbers like 2.14j, 2.0 + 2.3j, etc.)

String

The string can be defined as the sequence of characters represented in the quotation marks.

The following example illustrates the string handling in python.

str1 = 'hello javatpoint' #string str1

str2 = ' how are you' #string str2

print (str1[0:2]) #printing first two character using slice operator

print (str1[4]) #printing 4th character of the string

print (str1*2) #printing the string twice

print (str1 + str2) #printing the concatenation of str1 and str2

Output:

he

o

hello javatpointhello javatpoint

hello javatpoint how are you

List

Lists are similar to arrays in C. However; the list can contain data of different types. The items

stored in the list are separated with a comma (,) and enclosed within square brackets [].

We can use slice [:] operators to access the data of the list. The concatenation operator (+) and

repetition operator (*) works with the list in the same way as they were working with the strings.

example.

l = [1, "hi", "python", 2]

print (l[3:]);

print (l[0:2]);

print (l);

print (l + l);

print (l * 3);

Output:

[2]

[1, 'hi']

[1, 'hi', 'python', 2]

[1, 'hi', 'python', 2, 1, 'hi', 'python', 2]

[1, 'hi', 'python', 2, 1, 'hi', 'python', 2, 1, 'hi', 'python', 2]

Tuple

A tuple is similar to the list in many ways. Like lists, tuples also contain the collection of the items

of different data types. The items of the tuple are separated with a comma (,) and enclosed in

parentheses ().

A tuple is a read-only data structure as we can't modify the size and value of the items of a tuple.

Example -:

t = ("hi", "python", 2)

print (t[1:]);

print (t[0:1]);

print (t);

print (t + t);

print (t * 3);

print (type(t))

t[2] = "hi";

Output:

('python', 2)

('hi',)

('hi', 'python', 2)

('hi', 'python', 2, 'hi', 'python', 2)

('hi', 'python', 2, 'hi', 'python', 2, 'hi', 'python', 2)

Traceback (most recent call last):

File "main.py", line 8, in

t[2] = "hi";

TypeError: 'tuple' object does not support item assignment

Dictionary

Dictionary is an ordered set of a key-value pair of items. It is like an associative array or a hash

table where each key stores a specific value. Key can hold any primitive data type whereas value

is an arbitrary Python object.

The items in the dictionary are separated with the comma and enclosed in the curly braces {}.

example. -:

d = {1:'Jimmy', 2:'Alex', 3:'john', 4:'mike'};

print("1st name is "+d[1]);

print("2nd name is "+ d[4]);

print (d);

print (d.keys());

print (d.values());

Output:

1st name is Jimmy

2nd name is mike

{1: 'Jimmy', 2: 'Alex', 3: 'john', 4: 'mike'}

[1, 2, 3, 4]

['Jimmy', 'Alex', 'john', 'mike']

b) Write a python program to calculate factorial of given number using function.

Answer: The factorial of a number is the product of all the integers from 1 to that number.

For example, the factorial of 6 is 1*2*3*4*5*6 = 720. Factorial is not defined for negative numbers

and the factorial of zero is one, 0! = 1.

def recur_factorial(n):

if n == 1:

return n

else:

return n*recur_factorial(n-1)

num = 7

# check if the number is negative

if num < 0:

print("Sorry, factorial does not exist for negative numbers")

elif num == 0:

print("The factorial of 0 is 1")

else:

print("The factorial of", num, "is", recur_factorial(num))

Output

The factorial of 7 is 5040

c) Show the output for the following:

1. >>> a=[1,2,3]

>>>b=[4,5,6]

>>> c=a+b

2. >>>[1,2,3]*3

3.

>>>t=['a','b','c','d','e','f']

>>>t[1:3]=['x','y']

>>>print t

Answer:

1.

[1,2,3,4,5,6]

2.

[1,2,3,1,2,3,1,2,3]

3.

['a','x','y','d','e','f']

Q.6) Attempt any TWO of the following.

(12 Marks)

a) Describe Set in python with suitable examples.

Answer: A Set is an unordered collection data type that is iterable, mutable and has no duplicate

elements. Python's set class represents the mathematical notion of a set. The major advantage of

using a set, as opposed to a list, is that it has a highly optimized method for checking whether a

specific element is contained in the set. This is based on a data structure known as a hash table.

If Multiple values are present at the same index position, then the value is appended to that index

position, to form a Linked List. In, Python Sets are implemented using dictionary with dummy

variables, where key beings the members set with greater optimizations to the time complexity.

Set = set(["a", "b", "c"])

print("Set: ")

print(Set)

# Adding element to the set

Set.add("d")

print("\nSet after adding: ")

print(Set)

Output:

Set:

set(['a', 'c', 'b'])

Set after adding:

set(['a', 'c', 'b', 'd'])

b) Illustrate class inheritance in Python with an example.

Answer: Inheritance enable us to define a class that takes all the functionality from parent class

and allows us to add more. In this article, you will learn to use inheritance in Python.

It refers to defining a new class with little or no modification to an existing class. The new class is

called derived (or child) class and the one from which it inherits is called the base (or parent)

class.

Python Inheritance Syntax

class BaseClass:

Body of base class

class DerivedClass(BaseClass):

Body of derived class

Example -:

class Polygon:

def __init__(self, no_of_sides):

self.n = no_of_sides

self.sides = [0 for i in range(no_of_sides)]

def inputSides(self):

self.sides = [float(input("Enter side "+str(i+1)+" : ")) for i in range(self.n)]

def dispSides(self):

for i in range(self.n):

print("Side",i+1,"is",self.sides[i])

c) Design a class Employee with data members: name, department and salary. Create

suitable methods for reading and printing employee information.

Answer:

class Employee:

__name=""

__dep=""

__salary=0

def setData(self):

self.__name = input("Enter Name\t:")

self.__dep = input("Enter department\t:")

self.__salary = int(input("Enter Salary:"))

def showData(self):

print("Name\t:", self.__name)

print("Department\t:", self.__dep)

print("Salary\t:", self.__salary)

def main():

#Employee Object

emp=Employee()

emp.setData()

emp.showData()

if __name__=="__main__":

main()

Output -:

DIAGRAM 5

1. illustrate the use of method overriding explain with example

2. Illustrate data abstraction with proper example

3. State use of namespace in python

4.what is local and globle variables

5. List built in class attributes

6. What is object give example

7. List reading keyboard input function

1. use of method overriding example

>

-

when you have two methods with the same name that each perform different tasks.

-

the child class has access to the properties and functions of the parent class method while also extending additional functions of its own to the method

class Animal:

def Walk(self):

print('Hello, I am the parent class')

class Dog(Animal):

def Walk(self):

print('Hello, I am the child class')

print('The method Walk here is overridden in the code')

r = Dog()

r.Walk()

r = Animal()

r.Walk()

Output

The method Walk here is overridden in the code

Hello, I am the child class

Hello, I am the parent class

2. Illustrate data abstraction with proper example

>process of hiding the real implementation/carry out of an application from the user and emphasizing/importance only on usage of it.

-

For example, consider you have bought a new electronic gadget. Along with the gadget, you get a user guide, instructing how to use the application, but this user guide has no info regarding the internal working of the gadget.

3. State use of namespace in python

>

1. State the use of namespace in python

-The namespace helps the Python interpreter to understand what exact method or variable is trying to point out in the code.

-A namespace is a system that has a unique name for each and every object in Python

-Python itself maintains a namespace in the form of a Python dictionary

-the role of a namespace is like a surname

-One might not find a single "Alice" in the class there might be multiple "Alice" but when you particularly ask for "Alice Lee" or "Alice Clark"

2. local 😇 & global😈 variable

-😇A variable declared inside the function is called local function".

-😈Global variables are those which are not defined inside any function and have a global scope

3.list buit-in class attributes in python

−

1.__dict__

− Dictionary containing the class's namespace.

2.__doc__

− Class documentation string or none, if undefined.

3.__name__

− Class name.

4.__module__

− Module name in which the class is defined. This attribute is "__main__" in interactive mode.

5.__bases__

− A possibly empty tuple containing the base classes, in the order of their occurrence in the base class list.

6. What is object give example

>

collection of data (variables) and methods (functions) that act on those data. Similarly, a class is a blueprint for that object.

We can think of a class as a sketch (prototype) of a house. It contains all the details about the floors, doors, windows, etc. Based on these descriptions we build the house. House is the object.

7. List reading keyboard input function

>

two inbuilt functions to read the input from the keyboard

input ( prompt )

-The input from the user read as string and can assigned to a variable. After entering the value from the keyboard, we have to press the "Enter" button. Then the input() function reads the value entered by the user

raw_input ( prompt )

scan(),

readline(),

print().

Features

Applications

Uses

Advantage

Disadvantage

Statements

Identifiers

Loops

Modes

Methods

Functions:

-built in function

+math

+string

Operators

Variable

Modules

List

Set

Tuple

Dictionary

Features :

-

1. Easy To Learn & Use While Coding

2. Extensible Feature

3. Interpreted Language

4. Expressive Language

5. Cross-Platform Portable Language

6. Dynamic Memory Allocation

7. High-Level Interpreted Language

8. Graphical User Interface (GUI) Support:

9. Object-Oriented Language

10. Open Source Programming Language

11. Large Standard Library

12. Easy To Integrate

13. Embeddable

Applications :

1. Web Development

2. Game Development

3. Scientific and Numeric Applications

4. Artificial Intelligence and Machine Learning

5.Desktop GUI

6. Software Development

7. Enterprise-level/Business Applications

8. Education programs and training courses

9. Language Development

10. Operating Systems

11. Web Scraping Applications

12. Image Processing and Graphic Design Applications

Python uses

programming language is used globally to design and build 2D imaging software like Inkscape, GIMP, Paint Shop Pro, and Scribus. Also, Python is used in several 3D animation

Advantages & Disadvantages

😇It is easy to learn and use, and it has an extensive library.

😈Because of its elementary programming, users face difficulty while working with other programming languages.

😇Python increases productivity.

😈Python is a time-consuming language

It has a low execution speed.

😇It is very flexible.

😈There are many issues with the design of the language, which only gets displayed during runtime.

😇It has a very supportive community

😈 It is not suited for memory-intensive programs and mobile applications

different modes of python

-

Interactive Mode

Batch Mode

Script mode

Interactive Mode :

Interactive mode is a command line shell.

-mode allows us to write codes in Python command prompt (>>>)

-mode is used to test the features of the python, or to run a smaller script that may not be reusable.

Batch Mode :

Batch mode is mainly used to develop business applications

Script mode:

script mode programs can be written and stored as separate file with the extension .py and executed.

-Script mode is used to create and edit python source

Modules

are simply files with the ". py" extension containing Python code that can be imported inside another Python Program.

-is a file containing Python definitions and statements. A module can define functions, classes, and variables. A module can also include runnable code

Functions

-A function can be defined as the organized block of reusable code, which can be called whenever required.

-Python allows us to divide a large program into the basic building blocks known as a function

-The function contains the set of programming statements enclosed by {}

-

-A function can be called multiple times to provide reusability and modularity to the Python program.

The Function helps to programmer to break the program into the smaller part.

Python provide us various inbuilt functions like range() or print().

the user can create its functions, which can be called user-defined functions.

There are mainly two types of functions.

User-define functions

- The user-defined functions are those define by the user to perform the specific task.

Built-in functions - The built-in functions are those functions that are pre-defined in Python.

Math's built-in Functions: Here is the list of all the functions and attributes defined

in math module

Function

Description

ceil(x)

Return the Ceiling value. It is the smallest integer, greater or equal

to the number x.

copysign(x, y)

Returns x with the sign of y

cos(x)

Return the cosine of x in radians

exp(x)

Returns e**x

factorial(x)

Returns the factorial of x

floor(x)

Returns the largest integer less than or equal to x

fmod(x, y)

Returns the remainder when x is divided by y

gcd(x, y)

Returns the Greatest Common Divisor of x and y

log(x[, base])

Returns the Log of x, where base is given. The default base is e

log2(x)

Returns the Log of x, where base is 2

log10(x)

Returns the Log of x, where base is 10

pow(x, y)

Return the x to the power y value.

remainder(x, y) Find remainder after dividing x by y.

radians(x)

Convert angle x from degrees to radian

sqrt(x)

Finds the square root of x

sin(x)

Return the sine of x in radians

tan(x)

Return the tangent of x in radians

String build-in functions:

Python includes the following built-in methods to manipulate strings:

Function

Description

capitalize()

Converts the first character to upper case

count()

Returns the number of times a specified value occurs in a string

endswith()

Returns true if the string ends with the specified value

find()

Searches the string for a specified value and returns the position of

where it was found

index()

Searches the string for a specified value and returns the position of

where it was found

isalnum()

Returns True if all characters in the string are alphanumeric

isalpha()

Returns True if all characters in the string are in the alphabet

isdigit()

Returns True if all characters in the string are digits

islower()

Returns True if all characters in the string are lower case

isnumeric()

Returns True if all characters in the string are numeric

isspace()

Returns True if all characters in the string are whitespaces

isupper()

Returns True if all characters in the string are upper case

lower()

Converts a string into lower case

replace()

Returns a string where a specified value is replaced with a specified

value

rfind()

Searches the string for a specified value and returns the last position

of where it was found

rindex()

Searches the string for a specified value and returns the last position

of where it was found

split()

Splits the string at the specified separator, and returns a list

Strip()

Remove spaces at the beginning and at the end of the string:

startswith()

Returns true if the string starts with the specified value

title()

Converts the first character of each word to upper case

translate()

Returns a translated string

upper()

Converts a string into upper case

😇List Tuple Set Dictionary

List is a non-homogeneous data structure that stores the elements in single row and multiple rows and columns

😈Tuple is also a non-homogeneous data structure that stores single row and multiple rows and column

👽Set data structure is also non-homogeneous data structure but stores in single row

👻Dictionary is also a non-homogeneous data structure which stores key value pairs

😇List can be represented by [ ]

😈Tuple can be represented by

( )

👽Set can be represented by { }

👻Dictionary can be represented by { }

😇List allows duplicate elements 😈Tuple allows duplicate elements

👽Set will not allow duplicate elements Set will not allow duplicate elements and

👻dictionary doesn't allow duplicate keys.

😇List can use nested among all 😈Tuple can use nested among all

👽Set can use nested among all 👻Dictionary can use nested among all

😇Example: [1, 2, 3, 4, 5]

😈Example: (1, 2, 3, 4, 5)

👽Example: {1, 2, 3, 4, 5}

👻Example: {1, 2, 3, 4, 5}

😇List can be created using list() function

😈Tuple can be created using tuple() function.

👽Set can be created using set() function

👻Dictionary can be created using dict() function.

😇List is mutable i.e we can make any changes in list.

😈Tuple is immutable i.e we can not make any changes in tuple 👽Set is mutable i.e we can make any changes in set. But elements are not duplicated.

👻Dictionary is mutable. But Keys are not duplicated.

😇List is ordered

😈Tuple is ordered

👽Set is unordered

👻Dictionary is ordered (Python 3.7 and above)

😇Creating an empty list

l=[]

😈Creating an empty Tuple

t=()

👽Creating a set

a=set()

b=set(a)

👻Creating an empty dictionary

d={}

Python operator is a symbol that performs an operation on one or more operands. An operand is a variable or a value on which we perform the operation.

Python Operator falls into 7 categories:

Arithmetic

Relational

Assignment

Logical

Membership

Identity

Bitwise

Arithmetic Operators:

arithmetic operators for different mathematical operations. They are:

+ (Addition)

– (Subtraction)

* (Multiplication)

/ (Division)

** (Exponentiation)

// (Floor division)

% (Modulus)

Relational Operators:

They are also called comparison operators and they compare values.

> (Greater than)

< (Less than)

== (Equal to)

!= (Not equal to)

>= (Greater than or equal to)

<= (Less than or equal to)

Assignment Operators:

They perform an operation and assign a value.

= (Assign)

+= (Add and assign)

-= (Subtract and assign)

*= (Multiply and assign)

/= (Divide and assign)

%= (Modulus and assign)

**= (Exponentiation and assign)

//= (Floor-divide and assign

Logical Operators:

They can combine conditions.

and (Logical and)

or (Logical or)

not (Logical not)

Membership Operators:

check whether a value is in another. Python has 2 membership operators:

in

not in

Identity Operators:

check whether two values are identical. Python has 2 identity operators as well:

is

is not

a. is operator

The is operator returns True if the first value is the same as the second. Otherwise, it returns False.

Bitwise Operators:

They operate on values bit by bit.

& (Bitwise and)

(Bitwise or)

^ (Bitwise xor)

~ (Bitwise 1's complement)

<< (Bitwise left-shift)

>> (Bitwise right-shift)

a. Bitwise and

Loops

allows us to execute a statement or group of statements multiple times.

1 while loop

Repeats a statement or group of statements while a given condition is TRUE. It tests the condition before executing the loop body.

2 for loop

Executes a sequence of statements multiple times and abbreviates the code that manages the loop variable.

3 nested loops

You can use one or more loop inside any another while, for or do..while loop.

Built in package & user define package

User defined package: The package we create is called user-defined package.

2)

Built-in package: The already defined package