Converting to and from Python lists in NumPy - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to convert a NumPy array to a Python list.

NumPy

import numpy as np
arr = np.array([1, 2, 3])
py_list = arr.[1]()

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

Atolist()

Btolist

Cto_list

Dto_list()

Attempts:

3 left

💡 Hint

Common Mistakes

Using to_list() which does not exist.

Forgetting the parentheses after the method name.

The tolist() method converts a NumPy array to a Python list.

2fill in blank

medium

Complete the code to convert a Python list to a NumPy array.

NumPy

import numpy as np
py_list = [4, 5, 6]
arr = np.[1](py_list)

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

Afromlist

Basarray

Carray

Dtolist

Attempts:

3 left

💡 Hint

Common Mistakes

Using tolist() which converts arrays to lists.

Using fromlist which is not a NumPy function.

The np.array() function converts a Python list to a NumPy array.

3fill in blank

hard

Fix the error in the code to convert a nested Python list to a NumPy array.

NumPy

import numpy as np
nested_list = [[1, 2], [3, 4]]
arr = np.[1](nested_list)

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

Atolist

Barray

Casarray

Dfromlist

Attempts:

3 left

💡 Hint

Common Mistakes

Using tolist() which converts arrays to lists.

Using fromlist which is not a valid NumPy function.

Use np.array() to convert nested lists to multidimensional NumPy arrays.

4fill in blank

hard

Fill both blanks to create a list of lengths of strings from a list using list comprehension.

NumPy

words = ['apple', 'banana', 'cherry']
lengths = [[1] for [2] in words]

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

Alen(word)

Bword

Cw

Dlen(w)

Attempts:

3 left

💡 Hint

Common Mistakes

Using word as variable but len(word) as expression without matching names.

Using len(word) but loop variable is w (mismatch).

The list comprehension uses len(w) to get length and w as the loop variable.

5fill in blank

hard

Fill all three blanks to create a dictionary of word lengths for words longer than 5 characters.

NumPy

words = ['apple', 'banana', 'cherry', 'date']
length_dict = { [1]: [2] for [3] in words if len([3]) > 5 }

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

Aword

Blen(word)

Dw

Attempts:

3 left

💡 Hint

Common Mistakes

Using different variable names inconsistently.

Not matching the loop variable with the condition.

The dictionary comprehension uses word as key, len(word) as value, and loops with word.