DATA HANDLING CBSE CLASS 11 PYTHON SUBJECT

1. GVK CHINMAYA VIDYALAYA
SENIOR SECONDARY SCHOOL
Kothuru, Indukurupet, SPS Nellore
Data Handling
Class: 11 Subject: Python Teacher: C Vijaya

2. In programming, data type is an important concept.
Variables can store data of different types, and different types can do different things.
Python has the following data types built-in by default, in these categories:
Python Data Types
Text Type: str
Numeric Types: int, float, complex
Sequence Types: list, tuple, range
Mapping Type: dict
Set Types: set, frozenset
Boolean Type: bool
Binary Types: bytes, bytearray, memoryview

3. In Python, the data type is set when you assign a value to a variable:

4. Python Numbers
There are three numeric types in Python:
● int
● float
● complex
Variables of numeric types are created when you assign a value to them:

5. Output

6. String Literals
String literals in python are surrounded by either single quotation marks, or double quotation
marks.
'hello' is the same as "hello".
You can display a string literal with the print() function:
Eg:
a=”hello”
print(a)
Eg:
a=”””Welcome to gvkcv
At Indhukeurpet”””
print(a)

7. Strings are Arrays
Like many other popular programming languages, strings in Python are arrays of bytes
representing unicode characters.
However, Python does not have a character data type, a single character is simply a string with
a length of 1.
Square brackets can be used to access elements of the string.

9. Slicing
You can return a range of characters by using the slice syntax.
Specify the start index and the end index, separated by a colon, to return a part of the
string.

11. String Length
To get the length of a string, use the len() function.

12. Boolean Values
In programming you often need to know if an expression is True or False.
You can evaluate any expression in Python, and get one of two answers, True or
False.
When you compare two values, the expression is evaluated and Python returns the
Boolean answer:

15. Dictionary
A dictionary is a collection which is unordered, changeable and indexed. In Python dictionaries
are written with curly brackets, and they have keys and values.
Python Dictionaries

16. Output

17. Core Data Types

18. Every variable in python holds an instance of an object. There are two types of objects in python i.e.
Mutable and Immutable objects. Whenever an object is instantiated, it is assigned a unique object
id. The type of the object is defined at the runtime and it can’t be changed afterwards. However, it’s
state can be changed if it is a mutable object.
To summarise the difference, mutable objects can change their state or contents and immutable
objects can’t change their state or content.
● Immutable Objects : These are of in-built types like int, float, bool, string, unicode, tuple.
In simple words, an immutable object can’t be changed after it is created.
Mutable vs Immutable Objects in Python

21. Mutable Objects : These are of type list, dict, set . Custom classes are
generally mutable.

22. Every Python object has three key attributes associated to it
1. The type of an object
2. The value of an object
3. The id of an object

23. 1. The type of an object
The type of an object determines the operations that can be performed on the object.
Built-in function type() returns the type of an object.

24. 2. The value of an object
The value is the literal itself and for a variable the data iis the data-item(the variable) it is
currently referencing. Print statement can display the value of an object.

25. 3 .The id of an object
Id of an object is the memory location of the object.

31. Truth Value Testing
Value with truth value as false Values with truth value as truth
None
All the other values are
considered true
False (Boolean value False)
Zero for any numeric type,for example 0,0.0,0j
Any empty sequence eg:( ),[ ],
Any empty mapping eg: { }
www.gvkcv.in

32. The or operator combines two expressions,which make it operands.The or operator works in these
ways:
● Relational expressions as operands
● Numbers or strings or lists as operands
The or operator

33. Relational expressions as operands:
The or operator evaluates to true if either of its (relational) operands evaluates to True;False if both
operands evaluate to False.
Eg:
(4==4) or (5==8) results into True because first expression is True
5>8 or 5<2 results into False because both expressions are False

34. Numbers / Strings / list as operands:
In an expression x or y , if first operand has False then return second operand y as result.
Eg:
0 or 0 0 First expression is false so second expression is returned
0 or 8 8 First expression is false so second expression is returned
8 or 0 8 First expression is true hence first expression is returned
“Gvkcv” or “ ” “Gvkcv” First expression is true hence first expression is returned
“ “ or “gvkcv” “gvkcv” First expression is false hence second expression is returned
“ “ or “ “ “ “ First expression is false hence second expression is returned
“Python” or “gvkcv” “Python” First expression is true hence first expression is returned

35. The and operator:
● Relational expressions as operands
● Numbers or strings or lists as operands

36. Relational expressions as operands:
The and operator evaluates to True if both of its operands evaluate to True ; False if either or both
operands evaluate to False.
Eg:
(7==7) and (5==7) results False
(2>5) and (5<2) results False
5>2 and 2<5 results True

37. Numbers or Strings or Lists as operands:
In an expression x and y , if first operand has false then return first operand otherwise return second
operand.
Eg:
0 and 0 0 First expression is false so second expression is returned
0 and 8 0 First expression is false so second expression is returned
8 and 0 0 First expression is true hence first expression is returned
“Gvkcv” and “ ” “” First expression is true hence first expression is returned
“ “ and “gvkcv” “” First expression is false hence second expression is returned
“ “ and “ “ “ “ First expression is false hence second expression is returned
“Python” and “gvkcv” “gvkcv” First expression is true hence first expression is returned

38. The not operator:
The logical not operator negates or reverse the truth value of the expression.
Eg:
not 5 results into true
not 0 results into true
not -4 results into false