Variables in Python

Variables

•  Definition: A variable is nothing but a reserved memory location to store values.

• Variable is an entity to which the programmer can assign some values. Programmers choose the variable name which is meaningful. For example :

• In the following example we have declared the variable count to which value 10 is assigned with. This value is displayed by passing the variable name to print statement.

In [5]:

count = 10

print(count)

//The variable count is assigned with value 10 and then using print statement the value is displayed.

10

We can re‒declare the variables for assigning different values. For example –

count=10

print(count)

10

count = 1000

print(count)

 1000

//The variable count is initially assigned with 10 and then re‒assigned with the value 1000

Rules for variable names

•  Variable names must be meaningful. The variable name normally should denote its purpose. For example ‒ If the variable name is even_count, then clearly the total number of even elements is stored in this variable.

 • The variable names can be arbitrarily long. They contain both letters and digits but they cannot start with a number.

•  Normally variable names should start with lower case letters.

• The underscore character is allowed in the variable name. For example ‒ int total_elements.

Example:1

Evaluate the following expressions in python

24//6%3

float(4+int(2.39)%2)

2**2**3

Solution :

i) 1

ii) 4.0

iii) 256