Integer random with integers() in NumPy - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of numpy integers() with size parameter

What is the output of the following code snippet?

NumPy

import numpy as np
np.random.default_rng(seed=42).integers(low=5, high=10, size=3)

A [7 8 5]

B [6 5 5]

C [7 5 6]

D [7 5 5]

💡 Hint

Remember that integers() generates random integers in [low, high) range.

The integers() method with seed=42 produces the array [7 5 6] for the given parameters.

❓ data_output

intermediate

Shape and values from integers() with 2D size

What is the shape and one possible output of this code?

NumPy

import numpy as np
rng = np.random.default_rng(1)
rng.integers(0, 3, size=(2, 2))

A

Shape: (2, 2), Output: [[0 2]
 [1 0]]

B

Shape: (2, 2), Output: [[1 0]
 [0 2]]

C

Shape: (2, 2), Output: [[1 2]
 [0 1]]

D

Shape: (2, 2), Output: [[2 2]
 [1 0]]

💡 Hint

Check the shape parameter and the random seed effect.

With seed=1, integers(0,3,size=(2,2)) produces array([[0, 2], [1, 0]]).

🔧 Debug

advanced

Identify the error in this integers() call

What error does this code raise?

NumPy

import numpy as np
rng = np.random.default_rng()
rng.integers(low=10, high=5)

A No error, returns an integer

B TypeError: integers() missing required argument 'size'

C SyntaxError: invalid syntax

D ValueError: high must be greater than low

💡 Hint

Check the relationship between low and high parameters.

The high parameter must be greater than low; otherwise, ValueError is raised.

🧠 Conceptual

advanced

Range of values generated by integers()

Which statement about numpy's integers() output range is correct?

A integers(low, high) generates values in [low, high] inclusive

B integers(low, high) generates values in [low, high) exclusive of high

C integers(low, high) generates values in (low, high) exclusive of both ends

D integers(low, high) generates values in (low, high] inclusive of high only

💡 Hint

Think about typical Python range behavior.

numpy's integers() generates integers from low (inclusive) up to but not including high.

🚀 Application

expert

Generate a 1D array of 5 unique random integers between 0 and 9

Which code snippet correctly generates 5 unique random integers between 0 and 9 using numpy's integers()?

A

rng = np.random.default_rng()
rng.choice(10, size=5, replace=False)

B

rng = np.random.default_rng()
rng.integers(0, 10, size=5)

C

rng = np.random.default_rng()
rng.integers(0, 10, size=5, replace=False)

D

rng = np.random.default_rng()
rng.integers(0, 10, size=5, endpoint=True)

💡 Hint

integers() does not support replace=False, but choice() does.

To get unique integers, use choice() with replace=False. integers() does not have replace parameter.