Pie chart color customization in Matplotlib - Time & Space Complexity

Time Complexity: Pie chart color customization

O(n)

Understanding Time Complexity

We want to understand how the time to create a pie chart changes when we customize its colors.

How does adding colors affect the work matplotlib does?

Scenario Under Consideration

Analyze the time complexity of the following code snippet.

import matplotlib.pyplot as plt

sizes = [15, 30, 45, 10]
colors = ['red', 'blue', 'green', 'yellow']

plt.pie(sizes, colors=colors)
plt.show()

This code creates a pie chart with four slices, each colored differently.

Identify Repeating Operations

Identify the loops, recursion, array traversals that repeat.

• Primary operation: Drawing each slice of the pie chart.
• How many times: Once for each slice (4 times here).

How Execution Grows With Input

As the number of slices increases, matplotlib draws more slices and applies colors to each.

Input Size (n)	Approx. Operations
10	About 10 slice drawings and color applications
100	About 100 slice drawings and color applications
1000	About 1000 slice drawings and color applications

Pattern observation: The work grows roughly in direct proportion to the number of slices.

Final Time Complexity

Time Complexity: O(n)

This means the time to draw the pie chart grows linearly with the number of slices.

Common Mistake

[X] Wrong: "Adding colors makes the pie chart take much longer to draw, like exponentially more time."

[OK] Correct: Each slice just gets one color applied, so the extra work grows only with the number of slices, not much more.

Interview Connect

Understanding how adding features like colors affects performance helps you explain your code choices clearly and confidently.

Self-Check

"What if we added labels to each slice along with colors? How would the time complexity change?"