# Python math library | gamma() function

Python in its language allows various mathematical operations, which has manifolds application in scientific domain. One such offering of Python is the inbuilt `gamma()` function, which numerically computes the gamma value of the number that is passed in the function.

Syntax : math.gamma(x)
Parameters :
x : The number whose gamma value needs to be computed.

Returns : The gamma value, which is numerically equal to “factorial(x-1)”.

Code #1 : Demonstrating the working of gamma()

 `# Python code to demonstrate ` `# working of gamma() ` `import` `math ` ` `  `# initializing argument ` `gamma_var ``=` `6` ` `  `# Printing the gamma value. ` `print` `(``"The gamma value of the given argument is : "` `                       ``+` `str``(math.gamma(gamma_var))) `

Output:

`The gamma value of the given argument is : 120.0`

factorial() vs gamma()

The gamma value can also be found using `factorial(x-1)`, but the use case of `gamma()` is because, if we compare both the function to achieve the similar task, `gamma()` offers better performance.

Code #2 : Comparing `factorial()` and `gamma()`

 `# Python code to demonstrate ` `# factorial() vs gamma() ` `import` `math ` `import` `time  ` ` `  `# initializing argument ` `gamma_var ``=` `6` ` `  `# checking performance  ` `# gamma() vs factorial() ` `start_fact ``=` `time.time() ` `res_fact ``=` `math.factorial(gamma_var``-``1``) ` ` `  `print` `(``"The gamma value using factorial is : "`  `                              ``+` `str``(res_fact)) ` ` `  `print` `(``"The time taken to compute is : "` `        ``+` `str``(time.time() ``-` `start_fact)) ` ` `  `print` `(````' '````) ` ` `  `start_gamma ``=` `time.time() ` `res_gamma ``=` `math.gamma(gamma_var) ` ` `  `print` `(``"The gamma value using gamma() is : "` `                           ``+` `str``(res_gamma)) ` ` `  `print` `(``"The time taken to compute is : "`  `       ``+` `str``(time.time() ``-` `start_gamma)) `

Output:

```The gamma value using factorial is : 120
The time taken to compute is : 9.059906005859375e-06

The gamma value using gamma() is : 120.0
The time taken to compute is : 5.245208740234375e-06
```