Variables in python

start your journey in python programming

what is a variable?

a variable is a place to store the information for that value. The type of a variable can be changed according to future uses.

what is the type of variable: There are many types of variable which can be used in many programming languages to establish the accurate performance of the coding.

for example type of variable can be integer, float, string, etc.,

a = 60 integer type,

a=60.2 float type,

name = 'Datascience'string type

Python variable naming

There are some precise rules to what you can name a variable(called an identifier)

i. Python variables can only begin with a letter A-Z,a-z, or an underscore(_).

ii. The rest of the variables may contain all A-Z,a-z,underscore(_),and numbers(0–9)

iii. Python is case sensitive, Test and test are two different identifiers.

iv. Reserved words (keywords) cannot be used as identifier names.

and def False import not True as del finally in or try assert elif for is pass while break else from lambda print with class except global None raise yield continue exec if nonlocal return

for assign any value to the variable ‘=’(assignment operator )is used,

quantity=45here quantity is an integer type and the assigned identifier is 45 its value is 45.

45=quantity this is the wrong way of assigning you cant put an identifier on the right-hand side of the equal to sign if you assign code that causes the error as a syntax error.

Multiple assignments

age,city = 85,'UP'

print(age,city)

output

85 UP

can assign the same value to the multiple variables

>>> age=fav_num=7

>>> print(age,fav_num)

output

7 7

swapping variables

swapping is the interchanging of any values. when comparing other programming languages python programming is very easy to read and write code.

>>> a,b = 1,2

>>> a,b = b,a

>>> print(a,b)

output

2,1

Deleting variables: Deleting variables is possible by using the ‘del’ keyword

>>> a = 1

>>> del a

>>> a

output

NameError: name 'a' is not defined