Donut chart variation in Matplotlib - Step-by-Step Execution

Concept Flow - Donut chart variation

Prepare data and labels

↓

Create pie chart with wedges

↓

Create donut hole with wedgeprops

↓

Display donut chart

↓

END

The flow shows preparing data, creating a pie chart, creating the donut hole with wedgeprops, then displaying the chart.

Execution Sample

Matplotlib

import matplotlib.pyplot as plt
sizes = [30, 20, 25, 25]
labels = ['A', 'B', 'C', 'D']
plt.pie(sizes, labels=labels, wedgeprops=dict(width=0.4))
plt.show()

This code creates a donut chart by setting wedge width less than 1 to create a hole in the pie.

Execution Table

Step	Action	Data/Parameter	Result/Output
1	Define sizes	[30, 20, 25, 25]	Data ready for chart
2	Define labels	['A', 'B', 'C', 'D']	Labels ready for chart
3	Call plt.pie	sizes and labels, wedge width=0.4	Pie chart wedges created with hole
4	Call plt.show	None	Donut chart displayed on screen
5	End	None	Execution stops after showing chart

💡 Chart displayed and program ends

Variable Tracker

Variable	Start	After Step 1	After Step 2	After Step 3	Final
sizes	undefined	[30, 20, 25, 25]	[30, 20, 25, 25]	[30, 20, 25, 25]	[30, 20, 25, 25]
labels	undefined	undefined	['A', 'B', 'C', 'D']	['A', 'B', 'C', 'D']	['A', 'B', 'C', 'D']

Key Moments - 2 Insights

Why does setting wedgeprops width less than 1 create a donut shape?

Because wedgeprops width controls the thickness of pie slices. Setting it to 0.4 leaves a hole in the center, as shown in execution_table step 3.

What happens if we don't call plt.show()?

The chart will not display on screen. Execution_table step 4 shows plt.show triggers the display.

Visual Quiz - 3 Questions

Look at the execution_table, what is the value of 'sizes' after step 2?

A undefined

B ['A', 'B', 'C', 'D']

C [30, 20, 25, 25]

D [25, 25, 30, 20]

💡 Hint

Check variable_tracker row for 'sizes' after Step 2

At which step is the donut hole created in the chart?

A Step 3

B Step 4

C Step 1

D Step 2

💡 Hint

See execution_table step 3 where wedge width is set to 0.4

If wedgeprops width was set to 1, what would happen?

A Donut hole becomes bigger

B Chart becomes a full pie with no hole

C Chart will not display

D Labels disappear

💡 Hint

Recall wedge width controls slice thickness; 1 means full slices with no hole

Concept Snapshot

Donut chart variation in matplotlib:
- Use plt.pie() with wedgeprops={'width': value}
- width < 1 creates a hole (donut)
- Provide sizes and labels
- Call plt.show() to display
- Adjust width to control hole size

Full Transcript

This visual execution shows how to create a donut chart using matplotlib. First, we prepare the data sizes and labels. Then we call plt.pie with wedgeprops width set to 0.4 to create slices with a hole in the center. Finally, plt.show displays the donut chart. Variables sizes and labels remain unchanged after definition. The key step is setting wedgeprops width less than 1 to get the donut shape. Without plt.show, the chart won't appear. The quiz tests understanding of variable values and the effect of wedge width on the chart shape.