Pie chart color customization in Matplotlib - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What colors will the pie chart slices have?

Consider this code that creates a pie chart with custom colors. What colors will the slices be?

Matplotlib

import matplotlib.pyplot as plt
sizes = [30, 20, 50]
colors = ['red', 'green', 'blue']
plt.pie(sizes, colors=colors)
plt.show()

A Slices colored all gray

B Slices colored default matplotlib colors ignoring the list

C Slices colored red, green, and blue respectively

D Slices colored yellow, cyan, and magenta

💡 Hint

The colors list is passed to the pie function to set slice colors.

The colors parameter in plt.pie sets the slice colors in order. Here, red, green, and blue are used.

❓ data_output

intermediate

How many slices will be colored orange?

Given this pie chart code, how many slices will be orange?

Matplotlib

import matplotlib.pyplot as plt
sizes = [10, 20, 30, 40]
colors = ['orange', 'orange', 'blue', 'green']
plt.pie(sizes, colors=colors)
plt.show()

A 2 slices

B 1 slice

C 3 slices

D 0 slices

💡 Hint

Count how many times 'orange' appears in the colors list.

The colors list has 'orange' twice, so two slices will be orange.

🔧 Debug

advanced

Why does this pie chart ignore the colors list?

This code tries to color slices but all slices appear gray. What is the error?

Matplotlib

import matplotlib.pyplot as plt
sizes = [25, 25, 25, 25]
colors = ['red', 'green', 'blue', 'yellow']
plt.pie(sizes, color=colors)
plt.show()

A The pie function does not accept a colors parameter

B The sizes list must be strings, not integers

C The colors list must have hex codes, not names

D The parameter should be 'colors', not 'color'

💡 Hint

Check the exact parameter name for slice colors in plt.pie.

The correct parameter name is 'colors'. Using 'color' is ignored, so default colors appear.

❓ visualization

advanced

Which option shows a pie chart with a custom color palette?

You want a pie chart with slices colored purple, orange, and teal. Which code produces this?

A plt.pie([40, 30, 30], colors=['purple', 'orange', 'teal'])

B plt.pie([40, 30, 30], color=['purple', 'orange', 'teal'])

C plt.pie([40, 30, 30], colors=['red', 'green', 'blue'])

D plt.pie([40, 30, 30], colors=['purple', 'orange'])

💡 Hint

Use the correct parameter name and provide one color per slice.

Option A uses the correct 'colors' parameter with three colors matching three slices.

🚀 Application

expert

How to create a pie chart with alternating slice colors?

You want a pie chart with 6 slices where colors alternate between 'red' and 'blue'. Which code creates this pattern?

A

colors = ['red', 'blue'] * 3
plt.pie([10]*6, color=colors)
plt.show()

B

colors = ['red' if i % 2 == 0 else 'blue' for i in range(6)]
plt.pie([10]*6, colors=colors)
plt.show()

C

colors = ['red', 'blue', 'red', 'blue', 'red', 'blue']
plt.pie([10]*6, colors=colors)
plt.show()

D

colors = ['red', 'blue']
plt.pie([10]*6, colors=colors)
plt.show()

💡 Hint

Use a list comprehension to generate the alternating colors list.

Option B dynamically creates a list of 6 colors alternating red and blue, matching slice count.