Figure and axes creation in Data Analysis Python - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a new figure using matplotlib.

Data Analysis Python

import matplotlib.pyplot as plt
fig = plt.[1]()

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

Aplot

Bfigure

Cshow

Dsubplot

Attempts:

3 left

💡 Hint

Common Mistakes

Using plt.plot() instead of plt.figure()

Trying to call plt.show() to create a figure

The figure() function creates a new figure object in matplotlib.

2fill in blank

medium

Complete the code to add a single axes to the figure.

Data Analysis Python

fig = plt.figure()
ax = fig.[1](111)

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

Aadd_subplot

Badd_axes

Csubplot

Dplot

Attempts:

3 left

💡 Hint

Common Mistakes

Using add_axes() with a code instead of a rectangle

Calling subplot() directly on plt instead of on fig

The add_subplot() method adds an axes to the figure using a 3-digit code.

3fill in blank

hard

Fix the error in the code to create a figure and axes correctly.

Data Analysis Python

fig, ax = plt.[1]()

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

Afigure

Bsubplot

Csubplots

Dplot

Attempts:

3 left

💡 Hint

Common Mistakes

Using plt.figure() which returns only one object

Using plt.subplot() which returns a single axes

The subplots() function returns both a figure and axes objects.

4fill in blank

hard

Fill both blanks to create a figure with 2 rows and 1 column of subplots.

Data Analysis Python

fig, ax = plt.[1]([2], 1)

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

Asubplots

Bfigure

C2

D1

Attempts:

3 left

💡 Hint

Common Mistakes

Using plt.figure() instead of plt.subplots()

Swapping rows and columns numbers

plt.subplots(2, 1) creates a figure with 2 rows and 1 column of axes.

5fill in blank

hard

Fill all three blanks to create a figure with 3 columns and 2 rows of subplots.

Data Analysis Python

fig, ax = plt.[1]([2], [3])

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

Asubplots

B2

C3

D1

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping rows and columns numbers

Using plt.figure() instead of plt.subplots()

plt.subplots(2, 3) creates a figure with 2 rows and 3 columns of axes.

Practice

1. What does the plt.subplots() function return in matplotlib?

easy

A. A figure and one or more axes objects

B. Only a figure object

C. Only an axes object

D. A list of data points

Solution

1. Step 1: Understand plt.subplots() purpose

   The function is designed to create a figure and axes together for plotting.

2. Step 2: Check the return values

   It returns a tuple: the first is the figure, the second is the axes (single or array).

3. Final Answer:

   A figure and one or more axes objects -> Option A

4. Quick Check:

   plt.subplots() = (figure, axes) [OK]

Hint: Remember plt.subplots() returns figure and axes together [OK]

Common Mistakes:

• Thinking it returns only figure or only axes
• Confusing axes with data points
• Assuming it returns a plot directly

2. Which of the following is the correct syntax to create a figure with 2 rows and 3 columns of axes using matplotlib?

easy

A. fig, axes = plt.subplots(rows=3, cols=2)

B. fig, axes = plt.subplots(2, 3)

C. fig, axes = plt.subplots(3, 2)

D. fig, axes = plt.subplots(2*3)

Solution

1. Step 1: Recall plt.subplots() parameters

   The first argument is number of rows, the second is number of columns.

2. Step 2: Match the correct order

   To create 2 rows and 3 columns, use plt.subplots(2, 3).

3. Final Answer:

   fig, axes = plt.subplots(2, 3) -> Option B

4. Quick Check:

   Rows first, columns second in plt.subplots() [OK]

Hint: Remember rows first, columns second in plt.subplots() [OK]

Common Mistakes:

• Swapping rows and columns order
• Using keyword arguments incorrectly
• Passing a single number instead of two

3. What will be the shape of axes when running fig, axes = plt.subplots(2, 2)?

medium

A. A 2x2 numpy array of AxesSubplot objects

B. A list of 4 AxesSubplot objects

C. A single AxesSubplot object

D. A dictionary of axes objects

Solution

1. Step 1: Understand axes structure for multiple subplots

   When more than one subplot is created, axes is a 2D array matching the grid shape.

2. Step 2: Check the shape for 2 rows and 2 columns

   Axes will be a 2x2 numpy array of AxesSubplot objects.

3. Final Answer:

   A 2x2 numpy array of AxesSubplot objects -> Option A

4. Quick Check:

   Multiple subplots = axes array matching grid [OK]

Hint: Multiple subplots return axes array matching rows and columns [OK]

Common Mistakes:

• Expecting a flat list instead of 2D array
• Thinking axes is a single object always
• Confusing axes with figure

4. Identify the error in this code snippet:

fig, ax = plt.subplots(2, 2)
ax.plot([1, 2, 3], [4, 5, 6])

medium

A. fig and ax are swapped in assignment

B. plt.subplots() cannot create 2x2 axes

C. ax is an array, so ax.plot() causes an error

D. The plot data lists have different lengths

Solution

1. Step 1: Check the shape of ax from plt.subplots(2, 2)

   ax is a 2x2 array of axes, not a single axes object.

2. Step 2: Understand why ax.plot() fails

   Calling plot() on an array causes an AttributeError because arrays don't have plot method.

3. Final Answer:

   ax is an array, so ax.plot() causes an error -> Option C

4. Quick Check:

   Array of axes needs indexing before plot() [OK]

Hint: Index axes array before plotting when multiple subplots exist [OK]

Common Mistakes:

• Trying to plot on axes array directly
• Assuming plt.subplots(2,2) returns single axes
• Ignoring need to index axes for plotting

5. You want to create a figure with 3 subplots stacked vertically and set the figure size to 8 inches wide and 12 inches tall. Which code correctly does this?

hard

A. fig, axes = plt.subplots(1, 3, figsize=(12, 8))

B. fig, axes = plt.subplots(3, figsize=(8, 12))

C. fig, axes = plt.subplots(3, 1, size=(8, 12))

D. fig, axes = plt.subplots(3, 1, figsize=(8, 12))

Solution

1. Step 1: Determine subplot layout for vertical stacking

   3 subplots stacked vertically means 3 rows and 1 column.

2. Step 2: Set figure size correctly

   Use figsize=(width, height) with width=8 and height=12 inches.

3. Final Answer:

   fig, axes = plt.subplots(3, 1, figsize=(8, 12)) -> Option D

4. Quick Check:

   Rows=3, cols=1, figsize=(8,12) [OK]

Hint: Use figsize=(width, height) and rows, columns order [OK]

Common Mistakes:

• Swapping rows and columns
• Using wrong keyword 'size' instead of 'figsize'
• Confusing width and height order