Individual subplot customization in Matplotlib - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a figure with 2 subplots using matplotlib.

Matplotlib

import matplotlib.pyplot as plt
fig, axs = plt.subplots(1, [1])
plt.show()

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

A1

B2

C3

D4

Attempts:

3 left

💡 Hint

Common Mistakes

Using 1 instead of 2 for the number of subplots.

Confusing rows and columns in plt.subplots.

The plt.subplots function creates a figure and a set of subplots. Here, 1, 2 means 1 row and 2 columns, so 2 subplots.

2fill in blank

medium

Complete the code to set the title of the first subplot to 'First Plot'.

Matplotlib

import matplotlib.pyplot as plt
fig, axs = plt.subplots(1, 2)
axs[[1]].set_title('First Plot')
plt.show()

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

A0

B-1

C1

D2

Attempts:

3 left

💡 Hint

Common Mistakes

Using 1 instead of 0 for the first subplot index.

Using negative indices incorrectly.

Subplots are indexed starting at 0. The first subplot is axs[0].

3fill in blank

hard

Fix the error in the code to set the x-label of the second subplot to 'X Axis'.

Matplotlib

import matplotlib.pyplot as plt
fig, axs = plt.subplots(1, 2)
axs.[1](1).set_xlabel('X Axis')
plt.show()

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

Aplot

Bindex

Csubplot

D__getitem__

Attempts:

3 left

💡 Hint

Common Mistakes

Trying to call axs.subplot(1) which is not valid.

Using axs.plot(1) which is for plotting, not indexing.

To access the second subplot, use axs[1]. The __getitem__ method is called when using square brackets.

4fill in blank

hard

Fill both blanks to set the y-label of the first subplot to 'Y Axis' and change its background color to light gray.

Matplotlib

import matplotlib.pyplot as plt
fig, axs = plt.subplots(1, 2)
axs[[1]].set_ylabel('Y Axis')
axs[[2]].set_facecolor('lightgray')
plt.show()

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

A0

B1

C2

D-1

Attempts:

3 left

💡 Hint

Common Mistakes

Using different indices for the two actions.

Using invalid indices like 2 which is out of range.

Both actions target the first subplot, which is at index 0.

5fill in blank

hard

Fill both blanks to create a dictionary comprehension that maps each word to its length only if the length is greater than 3.

Matplotlib

words = ['data', 'science', 'is', 'fun']
lengths = {word: [1] for word in words if len(word) [2] 3}

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

A:

Blen(word)

C>

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using comma instead of colon between key and value.

Using wrong comparison operator in the condition.

Using word instead of len(word) as value.

The dictionary comprehension syntax is {key: value for item in iterable if condition}. Here, key is word, value is len(word), and the condition is len(word) > 3.

Practice

1. What is the correct way to change the title of the second subplot when using fig, axs = plt.subplots(2, 2)?

easy

A. Use plt.title('New Title')

B. Use axs[1].set_title('New Title')

C. Use fig.set_title('New Title')

D. Use axs[0, 1].set_title('New Title')

Solution

1. Step 1: Understand subplot indexing

   With plt.subplots(2, 2), axs is a 2x2 array. The second subplot in the first row is at position [0, 1].

2. Step 2: Set title for specific subplot

   Use axs[0, 1].set_title('New Title') to change only that subplot's title.

3. Final Answer:

   Use axs[0, 1].set_title('New Title') -> Option D

4. Quick Check:

   Indexing subplots by row and column = A [OK]

Hint: Use axs[row, col] to target specific subplot [OK]

Common Mistakes:

• Using axs[1] instead of axs[0, 1]
• Setting title on fig instead of axs
• Using plt.title affects whole figure, not subplot

2. Which of the following is the correct syntax to change the x-axis label of the first subplot in a 1D array of subplots fig, axs = plt.subplots(3)?

easy

A. axs[1].set_xlabel('X Label')

B. axs[0].set_xlabel('X Label')

C. axs.set_xlabel('X Label')

D. fig.set_xlabel('X Label')

Solution

1. Step 1: Identify subplot indexing in 1D array

   With plt.subplots(3), axs is a 1D array with indices 0, 1, 2. The first subplot is at index 0.

2. Step 2: Use set_xlabel on the correct subplot

   Use axs[0].set_xlabel('X Label') to set the x-axis label of the first subplot.

3. Final Answer:

   axs[0].set_xlabel('X Label') -> Option B

4. Quick Check:

   Index 0 for first subplot in 1D axs = D [OK]

Hint: Remember 1D axs uses zero-based indexing [OK]

Common Mistakes:

• Using axs[1] for first subplot
• Calling set_xlabel on fig or axs directly
• Confusing 1D and 2D axs indexing

3. What will be the color of the line in the third subplot after running this code?

import matplotlib.pyplot as plt
fig, axs = plt.subplots(2, 2)
axs[1, 0].plot([1, 2, 3], [4, 5, 6], color='green')
plt.show()

medium

A. Blue

B. Red

C. Green

D. Black

Solution

1. Step 1: Identify subplot position

   With plt.subplots(2, 2), subplots are indexed as [0,0], [0,1], [1,0], [1,1]. The third subplot is at [1,0].

2. Step 2: Check plot color argument

   The code sets color='green' for the line in subplot [1,0].

3. Final Answer:

   Green -> Option C

4. Quick Check:

   Color set explicitly to green = B [OK]

Hint: Check subplot index and color argument carefully [OK]

Common Mistakes:

• Assuming default blue color
• Confusing subplot index order
• Ignoring color parameter in plot

4. Identify the error in this code that tries to set the y-axis label of the last subplot:

fig, axs = plt.subplots(2, 2)
axs[2, 1].set_ylabel('Y Label')

medium

A. IndexError because axs has shape (2,2) and index (2,1) is out of range

B. AttributeError because set_ylabel is not a valid method

C. SyntaxError due to wrong indexing syntax

D. No error, code runs fine

Solution

1. Step 1: Check axs shape and indexing

   With plt.subplots(2, 2), axs shape is (2, 2), valid indices are 0 or 1 for each dimension.

2. Step 2: Identify invalid index

   Indexing axs[2, 1] tries to access third row (index 2), which does not exist, causing IndexError.

3. Final Answer:

   IndexError because axs has shape (2,2) and index (2,1) is out of range -> Option A

4. Quick Check:

   Index out of range error = C [OK]

Hint: Check subplot array shape before indexing [OK]

Common Mistakes:

• Assuming axs has more rows than created
• Confusing AttributeError with IndexError
• Using wrong indexing syntax

5. You want to create a 2x2 grid of subplots and set a different background color for each subplot: red, blue, green, and yellow respectively. Which code snippet correctly applies these colors?

hard

A. colors = ['red', 'blue', 'green', 'yellow']
fig, axs = plt.subplots(2, 2)
for ax, color in zip(axs.flat, colors):
ax.set_facecolor(color)

B. colors = ['red', 'blue', 'green', 'yellow']
fig, axs = plt.subplots(2, 2)
for i in range(4):
axs[i].set_facecolor(colors[i])

C. colors = ['red', 'blue', 'green', 'yellow']
fig, axs = plt.subplots(2, 2)
for i, j in range(2):
axs[i, j].set_facecolor(colors[i+j])

D. colors = ['red', 'blue', 'green', 'yellow']
fig, axs = plt.subplots(2, 2)
for ax in axs:
ax.set_facecolor(colors)

Solution

1. Step 1: Understand axs structure and iteration

   With plt.subplots(2, 2), axs is a 2D array. Using axs.flat flattens it to 1D for easy iteration.

2. Step 2: Apply colors correctly

   Using zip(axs.flat, colors) pairs each subplot with a color. Calling ax.set_facecolor(color) sets background color individually.

3. Final Answer:

   Use axs.flat with zip and set_facecolor for each subplot -> Option A

4. Quick Check:

   Flatten axs and zip with colors = A [OK]

Hint: Use axs.flat to loop all subplots in order [OK]

Common Mistakes:

• Trying to index axs as 1D without flattening
• Using axs as 2D but wrong color indexing
• Passing full color list to set_facecolor