Question

Explain the scope of variables with an example.

Answer 1

Scope of Variables:

Scope of a variable refers to the part of the program, where it is accessible, i.e., an area where you can refer (use) it. We can say that scope holds the current set of variables and their values.
The two types of scopes are the local scope and global scope.

(I) Local scope:

A variable declared inside the function’s body or in the local scope is called a local variable.

Rules of local variable:

1. A variable with a local scope can be accessed only within the function/block that it is created in.
2. When a variable is created inside the function/block; the variable becomes local to it.
3. A local variable only exists while the function is executing.
4. The formate arguments are also local to function.

Example: Create a Local Variable

def loc ( ):
y = 0 # local scope
print (y)
loc ( )
Output:
0
(II) Global Scope:

A variable, with global scope, can be used anywhere in the program. It can be created by defining a variable outside the scope of any function/block.

Rules of global Keyword:

The basic rules for global keywords in Python are:

1. When we define a variable outside a function, it’s global by default. You don’t have to use global keywords.
2. We use global keywords to read and write a global variable inside a function.
3. Use of global keywords outside a function has no effect

Example: Global variable and Local variable with the same name

x = 5 def loc ( ):
x = 10
print (“local x:”, x)
loc ( )
print (“global x:”, x)
Output:
local x: 10
global x: 5
In the above code, we used the same name ‘x’ for both global variable and local variable. We get a different result when we print the same variable because the variable is declared in both scopes, i.e. the local scope inside the function loc() and global scope outside the function loc ( ).
The output:- local x: 10, is called the local scope of the variable.
The output: – global x: 5, is called the global scope of the variable.