🔢 NumPy GCD (Greatest Common Divisor)

NumPy provides a vectorized function np.gcd() to compute the greatest common divisor of integers element-wise.

✅ 1. Basic GCD of Two Numbers

• GCD of 12 and 15 is 3 → largest number that divides both

✅ 2. GCD of Arrays

• Computes element-wise GCD

• gcd_arr[i] = GCD(arr1[i], arr2[i])

✅ 3. GCD with Scalars and Arrays

• Scalar is broadcasted to array automatically

✅ 4. GCD of Multiple Numbers

• NumPy gcd is element-wise. To find GCD of multiple numbers, use reduce:

• Computes GCD of all elements in the array

✅ 5. Notes & Tips

• GCD is always ≤ min(a, b)

• Useful in fractions simplification, ratio calculations, and number theory problems

• Works with integers only

🎯 Practice Exercises

1. Find the GCD of 36 and 60.

2. Find element-wise GCD of arrays [12, 18, 24] and [6, 9, 12].

3. Find the GCD of [8, 12, 16, 20] using np.gcd.reduce().