Understanding ufunc methods (reduce, accumulate) in NumPy - Interactive Quiz & Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to calculate the sum of all elements in the array using a ufunc method.

NumPy

import numpy as np
arr = np.array([1, 2, 3, 4])
result = np.add.[1](arr)
print(result)

Drag options to blanks, or click blank then click option'

Areduce

Baccumulate

Couter

Dreduceat

Attempts:

3 left

💡 Hint

Common Mistakes

Using accumulate instead of reduce returns intermediate sums, not the total sum.

Using outer or reduceat methods which have different purposes.

The reduce method applies the ufunc cumulatively to the elements, reducing the array to a single value, like summing all elements.

2fill in blank

medium

Complete the code to get the cumulative sum of elements in the array using a ufunc method.

NumPy

import numpy as np
arr = np.array([1, 2, 3, 4])
cum_sum = np.add.[1](arr)
print(cum_sum)

Drag options to blanks, or click blank then click option'

Aouter

Breduceat

Caccumulate

Dreduce

Attempts:

3 left

💡 Hint

Common Mistakes

Using reduce returns only the final sum, not intermediate sums.

Using outer or reduceat which do not produce cumulative sums.

The accumulate method returns intermediate results of applying the ufunc, giving the cumulative sum in this case.

3fill in blank

hard

Fix the error in the code to correctly compute the cumulative product of the array elements.

NumPy

import numpy as np
arr = np.array([1, 2, 3, 4])
cum_prod = np.multiply.[1](arr)
print(cum_prod)

Drag options to blanks, or click blank then click option'

Aaccumulate

Breduce

Creduceat

Douter

Attempts:

3 left

💡 Hint

Common Mistakes

Using reduce returns only the final product, not intermediate products.

Using reduceat or outer which are not for cumulative operations.

To get the cumulative product, use accumulate. The reduce method would return only the final product.

4fill in blank

hard

Fill both blanks to create a dictionary of cumulative sums for each number greater than 2 in the list.

NumPy

import numpy as np
numbers = [1, 3, 5, 2, 4]
cum_sums = {n: np.add.[1](np.arange(1, n+1)) for n in numbers if n [2] 2}
print(cum_sums)

Drag options to blanks, or click blank then click option'

Aaccumulate

B>

C>=

Dreduce

Attempts:

3 left

💡 Hint

Common Mistakes

Using reduce instead of accumulate returns only the total sum, not cumulative sums.

Using '>=' includes numbers equal to 2, which is not required.

Use accumulate to get cumulative sums. The condition > 2 filters numbers greater than 2.

5fill in blank

hard

Fill all three blanks to create a dictionary of final products for numbers less than or equal to 4 using a ufunc method.

NumPy

import numpy as np
numbers = [1, 3, 5, 2, 4]
final_products = {n: np.multiply.[1](np.arange(1, n+1)) for n in numbers if n [2] 4 and n [3] 0}
print(final_products)

Drag options to blanks, or click blank then click option'

Aaccumulate

B<=

C!=

Dreduce

Attempts:

3 left

💡 Hint

Common Mistakes

Using accumulate returns intermediate products, not the final one.

Using '<' instead of '<=' excludes 4, which should be included.

Using '==' instead of '!=' includes zero, which should be excluded.

Use reduce to get the final product. The condition <= filters numbers less than or equal to 4, and != excludes zero.