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Python factorial

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The Python factorial function is one of the Python Math functions used to find the factorial of a specified expression or a specific number. In this section, we discuss how to use factorial in Python Programming language with example.

Syntax of a Python factorial Function

The syntax of the factorial is

math.factorial(number);

Number: It can be a number or a valid numerical expression.

  • If the number argument is a positive integer, the factorial function returns the factorial of a given number.
  • If the number argument is Negative integer, Positive or Negative Decimals, factorial function return ValueError
  • And if it is not a number, the factorial function returns TypeError.

Python factorial Function Example

The Python factorial function finds the factorial of a given number. In this math factorial example, we are going to find the factorial of different data types and display the output.

# Python FACTORIAL Function

import math

Tup = (1, 2, 3, 4 , 5) # Tuple Declaration
Lis = [6, 7, 8, 5 , 9] # List Declaration

print('Factoial() Function on Positive Number = %.2f' %math.factorial(3))
print('Factoial() Function on Positive Decimal = %.2f' %math.factorial(6))

print('Factoial() Function on Tuple Item = %.2f' %math.factorial(Tup[2]))
print('Factoial() Function on List Item = %.2f' %math.factorial(Lis[4]))

print('Factoial() Function on Multiple Number = %.2f' %math.factorial(10 + 45 - 48))

print('Factoial() Function on String Value = ', math.factorial('Python'))

OUTPUT
Python FACTORIAL Function

ANALYSIS

  1. Within the first two statements, We used the factorial Function directly on Positive integers.
  2. Next two statements, We used the factorial Function on Tuple and List items. If you observe the above screenshot, the factorial function is working perfectly on them.
  3. Next statement, We tried factorial Function directly on multiple values.
  4. Here, we used the python factorial on the String value, and it returns TypeError: an integer is required (got type str) as output
  5. Next, We used factorial Function on Decimal value. As we said before, this is returning ValueError: factorial() only accepts integral values as output
  6. Last, We tried factorial Function on Negative value. As we said before, this is returning ValueError: factorial() not defined for negative values as output