Python Program for gamma() Function

In the previous article, we have discussed Python Program for tanh() Function
gamma() Function in Python:

The gamma function at a number is returned by the math.gamma() method.

Tip: Use the math.lgamma() method to find the log gamma value of a number.

Gamma Function’s Mathematical Formula:

Math.gamma(Number) = (Number – 1)!

Syntax:

math.gamma(x)

Parameters:

x: This is required. It is a number for which the gamma function must be found. If the number is a negative integer, a ValueError is returned. It throws a TypeError if it is not a number.

Return Value:

Returns a float value that represents the gamma function at x.

The gamma function returns the output if the number argument is a positive integer, positive or negative decimal.
The gamma function returns ValueError if the number argument is a negative integer.
If it’s not a number, the gamma function throws a TypeError.

Examples:

Example1:

Input:

Given first number = 6
Given second number = 2

Output:

The result after applying gamma() function on above given first number 6  =  120.0
The result after applying gamma() function on above given second number 2  =  1.0

Example2:

Input:

Given first number = -0.5
Given second number = 3

Output:

The result after applying gamma() function on above given first number -0.5  =  -3.544907701811032
The result after applying gamma() function on above given second number 3  =  2.0

Method #1: Using Built-in Functions (Static Input)

Approach:

Import math module using the import keyword.
Give the list as static input and store it in a variable.
Give the first number as static input and store it in another variable.
Apply math.gamma() function to the given first number to get the gamma value of a given number.
Store it in another variable.
Print the above result.
Similarly, do the same for the other number.
Apply math.gamma() function to the given list element and print it.
The Exit of Program.

Below is the implementation:

# Import math module using the import keyword.
import math
# Give the list as static input and store it in a variable.
gvn_lst = [2, -1.5, 3, 0.4]
# Give the first number as static input and store it in another variable.
gvn_numb1 = 6
# Apply math.gamma() function to the given first number to get the gamma value
# of a given number.
# Store it in another variable.
fnl_rslt = math.gamma(gvn_numb1)
# Print the above result
print("The result after applying gamma() function on above given first number",
      gvn_numb1, " = ", fnl_rslt)
# similarly do the same for the other number.
gvn_numb2 = 2
print("The result after applying gamma() function on above given second number",
      gvn_numb2, " = ", math.gamma(gvn_numb2))
# Apply math.gamma() function to the given list element and print it.
print(
    "The result after applying gamma() function on given list element gvnlst[1] = ", math.gamma(gvn_lst[1]))

Output:

The result after applying gamma() function on above given first number 6  =  120.0
The result after applying gamma() function on above given second number 2  =  1.0
The result after applying gamma() function on given list element gvnlst[1] =  2.3632718012073544

Method #2: Using Built-in Functions (User Input)

Approach:

Import math module using the import keyword.
Give the list as user input using list(),map(),input(),and split() functions.
Store it in a variable.
Give the first number as user input using the float(input()) function and store it in a variable.
Apply math.gamma() function to the given first number to get the gamma value of a given number.
Store it in another variable.
Print the above result.
Similarly, do the same for the other number.
Apply math.gamma() function to the given list element and print it.
The Exit of Program.

Below is the implementation:

# Import math module using the import keyword.
import math
# Give the list as user input using list(),map(),input(),and split() functions.
# Store it in a variable.
gvn_lst = list(map(float, input(
    'Enter some random List Elements separated by spaces = ').split()))
# Give the first number as user input using the float(input()) function
# and store it in a variable.
gvn_numb1 = float(input("Enter some random number = "))
# Apply math.gamma() function to the given first number to get the gamma value
# of a given number.
# Store it in another variable.
fnl_rslt = math.gamma(gvn_numb1)
# Print the above result
print("The result after applying gamma() function on above given first number",
      gvn_numb1, " = ", fnl_rslt)
# similarly do the same for the other number.
gvn_numb2 = float(input("Enter some random number = "))
print("The result after applying gamma() function on above given second number",
      gvn_numb2, " = ", math.gamma(gvn_numb2))
# Apply math.gamma() function to the given list element and print it.
print(
    "The result after applying gamma() function on given list element gvnlst[2] = ", math.gamma(gvn_lst[2]))

Output:

Enter some random List Elements separated by spaces = 1 3 2 5 7
Enter some random number = 1.5
The result after applying gamma() function on above given first number 1.5 = 0.886226925452758
Enter some random number = 3
The result after applying gamma() function on above given second number 3.0 = 2.0
The result after applying gamma() function on given list element gvnlst[2] = 1.0

Know all about Mathematical Functions in Python by going through our Python Mathematical Methods Examples well explained step by step.