Return the product of the argument and the return value of this method called (argument – one).Python Dictionaries Access Items Change Items Add Items Remove Items Loop Dictionaries Copy Dictionaries Nested Dictionaries Dictionary Methods Dictionary Exercise Python If.Else Python While Loops Python For Loops Python Functions Python Lambda Python Arrays Python Classes/Objects Python Inheritance Python Iterators Python Polymorphism Python Scope Python Modules Python Dates Python Math Python JSON Python RegEx Python PIP Python Try. Similarly, the function error handles when attempting to find the factorial of a negative number. The function returns a single integer and handles the special case of 0. This will be the terminating condition of the recursive method. One of the simplest ways to calculate factorials in Python is to use the math library, which comes with a function called factorial (). Check if the value of the argument is one, then return one from this method. Create a method which accepts one argument. A recursive method should have a condition which must cause it to return else it will keep on calling itself infinitely resulting in memory overflow.Ĭalculating the factorial of a number using the recursive method should work on the following algorithm.

A method which calls itself is called a recursive method. Recursion means a method calling itself until some condition is met. Read more: What is Null in Python Finding factorial of a number in Python using Recursion We are printing the factorial value when it ends.

This loop will exit when the value of ‘ n‘ will be ‘ 0‘.

On each iteration of the loop, we are decreasing the value of ‘n‘ by ‘ one‘. The while loop will run until the value of ‘n’ is greater than ‘one’. Similar to the above program, the variable ‘ fact‘ is used to hold the final factorial value. ‘ factorialUsingWhileLoop‘ method is used to find out the factorial using a while loop. The only difference is that we are using one ‘ while‘ loop instead of a ‘ for loop‘. Similar to the above program, we can use one ‘ while‘ loop to find out the factorial.

Factorial python