Difference between NumPy Random and Python Random

NumPy Random is from NumPy, whereas Python Random is a module in Python. That is, Python random is NOT part of NumPy.

This tutorial uses two examples to show the difference between NumPy Random and Python Random.

Example 1

Python Random’s randint only has parameters of the range, whereas NumPy random’s randint has the additional parameter of size.

Python:

random.randint(lowhigh): Return a random integer.

Numpy:

np.random.randint(low, high=None, size=None, dtype=int): Return (multiple) integers.

The following is the code example to demonstrate the difference. We can see that Python Random randint can only return 1 integer, whereas NumPy one can return more than 1 integer.

# importing Python Random
import random

# generate an integer via Python Random
Generated_number_1 = random.randint(2, 90) 
print("Generated by Python Random: \n", Generated_number_1 )

# importing NumPy 
import numpy as np

# generate an integer via NumPy Random
Generated_numbers = np.random.randint(2, 90, 3) 
print("Generated by NumPy Random: \n", Generated_numbers )

The following is the output from Python Random and NumPy Random.

Generated by Python Random: 
 13

Generated by NumPy Random: 
 [26 19 23]

Example 2

Python random.random will only return 1 floating number in [0,1), whereas NumPy’s random.rand() allows you to define the dimension of random numbers from [0,1).

Python:

random.random(): Return 1 random number in [0,1).

Numpy:

np.random.rand(d0d1dn): Return random numbers in [0,1) with different dimensions.

The following is the code example to demonstrate the difference between Python Random and NumPy Random.

# importing Python Random
import random

# generate a floating number in [0,1) via Python Random
Generated_number_1 = random.random() 
print("Generated by Python Random: \n", Generated_number_1 )

# importing NumPy 
import numpy as np

# generate floating numbers via NumPy Random
# d0=3, d1=4, size of 3x4 array in the range of [0, 1)
Array_numbers = np.random.rand(3,4) 
print("Generated by NumPy Random: \n",Array_numbers)

The following is the output. Python’s random.random() only returns 1 number, whereas NumPy’s random.rand() returns an array of 12 numbers.

Generated by Python Random: 
 0.7689563885870707

Generated by NumPy Random: 
 [[0.07768637 0.92770737 0.37410864 0.62537941]
 [0.83826093 0.08792431 0.09093518 0.95346045]
 [0.05844943 0.32099627 0.49624559 0.30395634]]

Further Reading