Global keyword in the python example
Example 1: Accessing global Variable From Inside a Function
Python3
# global variable a = 15 b = 10 # function to perform addition def add(): c = a + b print (c) # calling a function add() |
Output:
25
If we need to assign a new value to a global variable, then we can do that by declaring the variable as global.
Example 2: Modifying Global Variable From Inside the Function
Python3
a = 15 # function to change a global value def change(): # increment value of a by 5 b = a + 5 a = b print (a) change() |
Output:
UnboundLocalError: local variable 'a' referenced before assignment
This output is an error because we are trying to assign a value to a variable in an outer scope. This can be done with the use of a global variable.
Example 3: Changing Global Variable From Inside a Function using global
Python3
x = 15 def change(): # using a global keyword global x # increment value of a by 5 x = x + 5 print ( "Value of x inside a function :" , x) change() print ( "Value of x outside a function :" , x) |
Output:
Value of x inside a function : 20 Value of x outside a function : 20
In the above example, we first define x as a global keyword inside the function change(). The value of x is then incremented by 5, i.e. x=x+5 and hence we get the output as 20. As we can see by changing the value inside the function change(), the change is also reflected in the value outside the global variable.
Global keyword in Python
In this article, we will cover the global keyword, the basic rules for global keywords in Python, the difference between the local, and global variables, and examples of global keywords in Python.