In Python, math module contains a number of mathematical operations, which can be performed with ease using the module. math.factorial() function returns the factorial of desired number.
Syntax: math.factorial(x) Parameter: x: This is a numeric expression. Returns: factorial of desired number. Time Complexity: O(n) where n is the input number. Auxiliary space: O(1)
Code #1:
Python3
# Python code to demonstrate the working of factorial() # importing "math" for mathematical operations import math x = 5 # returning the factorial print ( "The factorial of 5 is : " , end = "") print (math.factorial(x)) |
The factorial of 5 is : 120
Code #2:
Python3
# Python code to demonstrate the working of factorial() # importing "math" for mathematical operations import math x = 5 y = 15 z = 8 # returning the factorial print ( "The factorial of 5 is : " , math.factorial(x)) print ( "The factorial of 15 is : " , math.factorial(y)) print ( "The factorial of 8 is : " , math.factorial(z)) |
Output:
The factorial of 5 is : 120 The factorial of 15 is : 1307674368000 The factorial of 8 is : 40320
Code #3: Throws ValueError if x is not integer
Python3
# Python code to demonstrate the working of factorial() # importing "math" for mathematical operations import math # when x is not integer print ( "math.factorial(13.7) : " , math.factorial( 13.7 )) |
Output:
ValueError: factorial() only accepts integral values