Percentage labels in Matplotlib - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of percentage labels in a matplotlib pie chart?

Percentage labels show the part each slice represents of the whole, making it easier to understand proportions visually.

beginner

How do you add percentage labels to a pie chart in matplotlib?

Use the autopct parameter in plt.pie() and set it to a format string like '%1.1f%%' to display percentages with one decimal place.

beginner

What does the format string '%1.1f%%' mean in the context of percentage labels?

It means show a floating-point number with at least one digit before and one digit after the decimal point, followed by a percent sign.

intermediate

Can you customize the appearance of percentage labels in matplotlib pie charts?

Yes, you can customize font size, color, and style by using additional parameters like textprops in plt.pie().

beginner

Why might you want to use percentage labels instead of raw values in a pie chart?

Percentage labels help viewers quickly understand the relative size of each slice compared to the whole, which is often more meaningful than raw numbers.

Which parameter in plt.pie() adds percentage labels to slices?

A colors

B labels

C autopct

D explode

The autopct parameter formats and displays percentage labels on pie chart slices.

What does the format string '%1.0f%%' display in percentage labels?

A Percentage with no decimal places

B Percentage with one decimal place

C Raw values without percentage sign

D Percentage with two decimal places

The '%1.0f%%' format shows percentages rounded to whole numbers with no decimals.

How can you change the font size of percentage labels in matplotlib pie charts?

A Use the <code>textprops</code> parameter with a dictionary including <code>{'fontsize': value}</code>

B Change the <code>autopct</code> string

C Set the <code>labels</code> parameter

D Use the <code>colors</code> parameter

The textprops parameter lets you customize text properties like font size.

If you want to show percentages with one decimal place, which autopct value should you use?

A '%1.0f%%'

B '%1.1f%%'

C '%2.1f%%'

D '%0.1f%%'

The '%1.1f%%' format shows one digit before and one digit after the decimal point.

What is the main benefit of adding percentage labels to pie charts?

A They change the colors of slices

B They explode slices

C They add legends automatically

D They help viewers understand the relative size of each slice

Percentage labels make it easier to see how big each slice is compared to the whole.

Explain how to add and customize percentage labels in a matplotlib pie chart.

Think about the parameters in plt.pie() that control labels and text style.

Why are percentage labels useful in pie charts compared to raw values?

Consider what helps people quickly grasp data proportions.