Style sheets (ggplot, seaborn, dark_background) in Matplotlib - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ visualization

intermediate

Effect of ggplot style on a line plot

You run the following code to plot a simple line graph using matplotlib with the ggplot style applied. What will be the main visible difference compared to the default style?

Matplotlib

import matplotlib.pyplot as plt
plt.style.use('ggplot')
plt.plot([1, 2, 3, 4], [10, 20, 25, 30])
plt.show()

A The plot will have a gray background with white grid lines and red plot lines.

B The plot will have no grid and blue plot lines on a white background.

C The plot will have a dark background with bright colored lines and no grid.

D The plot will have a white grid with red lines and a light gray background.

💡 Hint

Think about how ggplot style changes the background and grid colors.

The ggplot style in matplotlib sets a gray background with white grid lines and red plot lines by default. This mimics the ggplot2 style from R.

❓ Predict Output

intermediate

Output colors with dark_background style

What color will the line plot be when using the dark_background style with the following code?

Matplotlib

import matplotlib.pyplot as plt
plt.style.use('dark_background')
plt.plot([1, 2, 3], [4, 5, 6])
plt.show()

A The line will be blue on a gray background.

B The line will be black on a white background.

C The line will be white on a black background.

D The line will be red on a white background.

💡 Hint

Consider what the dark_background style does to the figure background and default line colors.

The dark_background style sets the figure background to black and the default line color to white for good contrast.

❓ data_output

advanced

Number of grid lines with seaborn style

Using the seaborn style, you plot a line graph with x values from 0 to 4 and y values as their squares. How many vertical grid lines will appear by default?

Matplotlib

import matplotlib.pyplot as plt
plt.style.use('seaborn')
plt.plot(range(5), [x**2 for x in range(5)])
plt.show()

A No vertical grid lines

B 5 vertical grid lines

C 4 vertical grid lines

D 6 vertical grid lines

💡 Hint

Check how matplotlib sets ticks and grids by default with seaborn style.

By default, matplotlib places ticks at the edges and between points, so for 5 x values, 6 vertical grid lines appear with seaborn style.

🧠 Conceptual

advanced

Understanding style sheet impact on plot elements

Which of the following statements about matplotlib style sheets ggplot, seaborn, and dark_background is correct?

A <code>seaborn</code> style adds a white grid on a light gray background and changes font sizes.

B <code>ggplot</code> style uses a dark background and bright colored lines by default.

C <code>dark_background</code> style sets a white background with black grid lines.

D <code>seaborn</code> style disables grid lines by default.

💡 Hint

Recall the visual themes each style sheet applies.

The seaborn style applies a light gray background with white grid lines and adjusts font sizes for clarity. The other options incorrectly describe the styles.

🔧 Debug

expert

Why does this style sheet code raise an error?

You run this code but get a FileNotFoundError. What is the cause?

Matplotlib

import matplotlib.pyplot as plt
plt.style.use('seaborn-dark')
plt.plot([1, 2, 3], [3, 2, 1])
plt.show()

A The plot data lists have different lengths causing an error.

B The style name 'seaborn-dark' does not exist in matplotlib's default styles.

C The matplotlib module is not imported correctly.

D The plot command is missing a required argument.

💡 Hint

Check the exact style sheet names available in matplotlib.

The style seaborn-dark is not a valid default style in matplotlib, so trying to use it raises a FileNotFoundError.