The GCD (Greatest Common Divisor), also known as HCF (Highest Common Factor) is the biggest number that is a common factor of both of the numbers.
Example
Find the HCF of the following two numbers:
import numpy as np
num1 = 6
num2 = 9
x = np.gcd(num1, num2)
print(x)Returns: 3 because that is the highest number both numbers can be divided by (6/3=2 and 9/3=3).
To find the Highest Common Factor of all values in an array, you can use the reduce() method.
Example
Find the GCD for all of the numbers in the following array:
import numpy as np
arr = np.array([20, 8, 32, 36, 16])
x = np.gcd.reduce(arr)
print(x)Returns: 4 because that is the highest number all values can be divided by.