Python functions allow breaking down code into reusable blocks to perform tasks. There are several types of functions including built-in, user-defined, and anonymous functions. User-defined functions are defined using the def keyword and can take in parameters. Functions can return values using the return statement. Functions are called by their name along with any arguments. Arguments are passed into parameters and can be positional, keyword, or have default values. Functions increase code reuse and readability.

1. Introduction to Python

2. What is Python ?
What you can do with it ?
Why it is so popular ?

3. Free and Open Source
High-level programming language

4. Free and Open Source
High-level, multi-purpose programming
language
Developed by Guido Van Rossum in the
late 1980s
Python is an interpreter-based
language

5. Portable, and Extensible
Python can be integrated with other popular programming
technologies like C, C++, Java, ActiveX, and CORBA.
Dynamic Typing
Supports procedural, object-oriented, & functional programming

6. What you can do with it ?

7. Desktop
Application

8. Desktop Application
Mobile Application

9. 9

10. Why it is so popular ?

11. High-Level
Huge Community
Large Ecosystem
Platform-Independent

12. 12
What can you do with Python
Develop web applications
Implementing machine learning algorithms such as Scikit-learn, NLTK
and Tensor flow .
Computer vision – Face detection , color detection while using OpenCV and python
Raspberry Pi – You can even build a robot and automate your home.
PyGame – Gaming applications

15. Is a reserved memory location to store
values
Variable Name
Every value in Python has
data type.
12
Computer memory
Age
0
Address
(index)
Data
Variables are used to store data, they take
memory space based on the type of value we
assigning to them.
Age = 12

16. 16
Names cannot start with a number ,
No spaces in the names, use underscore _ instead
Special characters are not allowed as variable names
income@, <>, ?, ! , (), #,$ ,% , ^, &,*,~,- +
Variable Names and Naming rules
Variables in Python are case sensitive
It can only start with a character or an underscore

18. 20
Name Type Description
Integers int Whole numbers, such as 8 12 400
Floating Point float Numbers with a decimal point 3.3, 14.5, 500.0
Strings Str Ordered sequence of characters
“hello” , “Sammy”, “2000”, “*$LL”
Lists List Ordered sequence of objects [10, “hello world”, 112.4]
Dictionaries dict Unordered key:value pairs {“key”:”value”}
Tuples tup Ordered immutable sequence of objects (30,”Bye”, 111.32)
Sets Set Unordered collection of unique objects (10,20)
Booleans Bool Logical value indicating True or False
Data Types

19. type()
21

20. Type conversions
22
>>> float(22//5)
4.0
>>> int(4.5)
4
>>> int(3.9)
3
>>> round(3.9)
4
>>> round(3)
3

21. strings
23

22. String formatting
24
There are multiple ways to format strings for printing variables
in them
Myvar= “Hello”
Print(myvar + “World”)
This is knowns as string interpolation

23. String formatting
25
.fomat() method
Myvar= “Hello”
Print(myvar + “World”)
This is knowns as string interpolation
f-strings (formatted string literals)

24. String functions
26
index()
casefold()
center()
count()
endswith()
expandtabs()
isalnum()
isalpha()
isdecimal()
isidentifier()
islower()
str1.isnumeric()
str1.join()

25. Indexing and Slicing with Strings
27

26. Working with string data type
28

27. Booleans in Python

28. 30
Booleans are two constant objects
It has only two possible values
Booleans are considered as numeric type in Python
Booleans
1. True
2. False
True == 1
False == 0
None as a Boolean value
Bool(None)
bool(3), bool(-3), bool(0) Nonzero integers are
truth
bool() method to convert a value to Boolean()

29. 31
Boolean operators are those that take Boolean inputs and
return Boolean results
and operator can be defined in terms of ‘not’ and ‘or’
Boolean operators
Boolean operators are and , not, or
or operator can be defined in terms of ‘not’ and ‘and’

30. Conditional and control flow

31. Provides us with 3 types of control
statements
Conditional Programming
Used to control the order of execution of the program based on
the values and logic
continue
break
pass

32. 34
expression: It’s the condition that needs to evaluated and
return a boolean (true/false)value.
statement: statement is a general python code that executes if
the expression returns true.
Control Structures

33. Loop Control Statements

34. 36
Loops
Loop statements are used to execute the block of the code repeatedly for
a specified number of times
There are three types of loops
Python for loop
Python while loop
Python nested loop

35. 38
while Loop
Syntax :
while test_expression:
#statement(s)
While loop will execute a block of statement as long as test expression is true

36. 39
while ..else Loop
While loop will execute a block of statement as long as test expression is true
while test:
statements
if test: break # Exit loop now, skip else if present
if test: continue # Go to top of loop now, to test1
else:
statements # Run if we didn't hit a 'break'

37. 40
continue statement
forces the loop to continue or execute the next iteration
When the continue statement is executed in the loop, the code inside the loop following
the continue statement will be skipped and the next iteration of the loop will begin.

38. 41
break statement
The break statement causes an immediate exit from a loop

39. 42
Nested for and while loops
Syntax : nested for loop
for <iterator_var1> in <iterable_object1>:
for <iterator_var2> in <iterable_object2>:
#statement(s)
#statement(s)
Loop statement inside another loop statement
Syntax : nested while loop
while <exp1>:
while<exp2>
#statement(s)
#statement(s)

40. 43
break statement
The break statement causes an immediate exit from a loop

41. 44
Nested for and while loops
Syntax : nested for loop
for <iterator_var1> in <iterable_object1>:
for <iterator_var2> in <iterable_object2>:
#statement(s)
#statement(s)
Loop statement inside another loop statement
Syntax : nested while loop
while <exp1>:
while<exp2>
#statement(s)
#statement(s)

42. Sets in Python

43. 46
Sets
Identified by curly braces
-{‘Raja’,’Ashok’,’Alok’}
Sets do not support indexing
A set an unordered collection data type that
holds an unordered collection of unique elements
set is iterable , mutable and has no duplicate

44. 47
Description Commands
Add item to set x x.add(item)
Remove an item x.remove(item)
get length of x len(x)
Check membership in x item in x
item not in x
Pop random item from set x x.pop()
Delete all items from x x.clear()
Basic Operations on Set

45. 48
Basic Operations on Set
A set is a python data type that holds an unordered collection of unique elements
Identified by curly braces
-{‘Raja’,’Ashok’,’Alok’}
Can only contain unique elements
Duplicates are eliminated
Sets do not support indexing

46. 49
Frozen sets
Frozen sets in Python are immutable
objects

47. 50
Ranges
range is another kind of immutable sequence type
ranges are also called as generators
Note that the range includes the
lower bound and excludes the
upper bound.
If we pass a single parameter to the range function, it is used as the upper bound
If we use two parameters, the first is the lower bound and the second is the upper bound.
If we use three, the third parameter is the step size.
The default lower bound is zero, and the default step size is one

48. Sets, Loops , & Functions
in Python

49. Functions in Python

50. What is a function ?
Why use functions ?
Types of functions ?
Functions Vs Methods
Function Signatures - Parameter Vs Arguments
User-Defined functions
The return statement
How to call a function
How to add docstrings to a function
Function arguments in python
Global Vs Local Variables
Recursive & Anonymous functions
Using main() as a function
Function as an argument
Function as return value
Map and filter() function
inner function & Decorator
Positional Vs Keyword arguments

51. It’s a block of code using which you want to carry out a specific task repeatedly
A function may contain zero or more than one arguments
What are functions ?

52. Increases readability
Eliminate redundancy
Why to use functions ?
Reduces coupling

53. Built-in functions, such as help() to ask for help, min() to get the minimum value,
print() to print an object to the terminal
User-Defined Functions (UDFs), which are functions that users create to help them
out;
Types of functions
Anonymous functions, which are also called lambda functions because they are not
declared with the standard def keyword

54. How to define user-defined functions ?
Syntax
def functionName(<parameter list>):
statement 1
statement 2
…
return expression
is used to return a value from a function
def net_sal(basic, hra, loan):
keyword
return Nsal
Here, basic, hra, and loan are called parameters of net_sal()
Also note that, basic, hra, and loan are variables ,
local to my function net_sal()

55. 59
How to call a function ?
def net_sal(basic, hra, loan):
Gsal = basic + hra
Calling a function is Python is similar to other programming languages
Also note that, basic, hra, and loan are variables ,
local to my function net_sal()
Nsal = Gsal - loan
return Nsal
net_sal(100000,22000,5000)
Syntax
function_name(arg1, arg2,arg3)
Here, basic, hra, and loan are the arguments of net_sal function
basic, hra, and loan are passed by reference
The memory addresses of basic, hra, and loan are passed
When we call the function

56. 60
Positional arguments
def net_sal(basic, hra, loan):
# code here
Most common way of assigning arguments to parameters:
via the order in which they are passed
When we call the function
net_sal(basic,hra, loan)
basic = 132000
hra = 22000
loan = 5000
basic = 128000
hra = 21000
loan = 6000
Its positional arguments

57. 61
Keyword arguments
def net_sal(basic, hra, loan):
# code here
When we call the function
net_sal(basic=132000,hra = 22000, loan = 5000)
basic = 132000
hra = 22000
loan = 5000
basic = 128000
hra = 21000
loan = 6000
Its keyword arguments
Once you have defined the keyword argument , you must specify the
Keyword for all the other arguments
net_sal(132000, hra=22000, 5000)
Keyword = value
Like positional args, the no. of args and parameters must still match

58. 62
Keyword arguments
When we call the function
net_sal(132000,hra = 22000, loan = 5000)
net_sal(132000, 22000, loan = 5000) Its keyword arguments
Can I call a function using both positional and keyword arguments ??
net_sal(132000, hra=22000,
5000)

59. 63
Default argument values
def net_sal(basic, hra=22000, loan=5000):
# code here
When we call the function
net_sal(132000)
net_sal(basic=132000,hra = 22000)
net_sal(hra=22000, basic=132000)
When you use keyword
Argument the order doesn’t matter

60. 64
Arguments in summary
Positional arguments must agree in order and number with the parameters
declared in the function definition
Keyword arguments must agree with declared parameters in number, but they may be
specified in arbitrary order
Default parameters allow some arguments to be omitted when function is called