PYTHON-FUNDAMENTALS: CONSTANTS, VARIABLES AND DATA TYPES

hi,everyody
I am kavin. I am going to write which I learnt I my class.

Variables

A variable in Python is a symbolic name that references or points to an object. Once a variable is assigned a value, it can be used to refer to that value throughout the program. Variables act as containers for storing data values.

How to name a variables

1.Start with a letter or an underscore.
2.Followed by letters, digits, or underscores.
3.Case-sensitive
4.Don't use Python Keywords

Examples of Valid Variable Names:
my_variable
variable1
_hidden_variable
userName

Assigning Values to Variables

In Python, the assignment operator = is used to assign values to variables. The syntax is straightforward: variable_name = value.
eg:

>>>name="kavin"
>>>print(name)

>>>kavin

Multiple Assignments

Python allows you to assign values to multiple variables in a single line. This can make your code more concise and readable.
eg:

>>>a,b,c=1,2,3
>>>print(a,b,c)

Variable Types

Python is a dynamically typed language, which means you don’t need to declare the type of a variable when assigning a value to it. The type is inferred at runtime based on the assigned value.
eg:

>>>my_variable="10"

>>>my_variable is an integer

You can check the type of a variable using the type() function.
eg:

>>>type("hello")

>>><class'str'>

Constants

In Python, constants are variables whose values are not meant to change. By convention, constants are typically written in all uppercase letters with underscores separating words.
eg:

>>>PI=22/7

Data Types

Data types are the different kinds of values that you can store and work with.

1.Numeric Types
*Integer (int): Whole numbers.

>>>value=23

*Float (float): Decimal numbers.

>>>value=23.5

*Complex (complex): Complex numbers.

>>>value=2+3j

2. Text Type

String (str): Sequence of characters.
eg:

>>>message="hello mac"

3. Boolean Type

Boolean (bool): Represents True or False.
eg:

>>>my_project=True

4. None Type

NoneType: Represents the absence of a value
eg:

>>>result=none

5. Sequence Types

*List (list): Ordered, mutable collection
eg:

>>>fruits=[apple,cherry,mango]

*Tuple (tuple): Ordered, immutable collection.
eg:

>>>coordinates(3,4)

*Range (range): Sequence of numbers.
eg:

>>>number=range(1,10)

6. Mapping Type

Dictionary (dict): Unordered, mutable collection of key-value pairs.
eg:

>>>person={"name":"kavin","url":"https://www.kavin.com"}

7.Set Type

Set (set): Unordered collection of unique elements.
Eg:

>>>unique_number={2,3,4}

Frozenset (frozenset): Immutable set.
eg:

>>>frozen_set=frozena([2,3,4])

Checking Data Type

Syntax: type(variable_name)
eg:

>>>name="kavin"
>>>print(type(name))

>>> <class'int'>

this is the things which i learnt in the class of Variables, Constants and Data Types.
Thank You

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