Pie plots are charts used to show how a total is divided into parts. They are most useful when you want to display proportions, such as market share by company, budget split by category, or share of sales by product group. A pie plot works best when the number of categories is small and the differences are clear.
A pie plot shows each category as a slice, where the size of the slice represents its percentage of the whole. Because pie plots focus on share, they are good for simple messages like “Category A contributes the largest share” or “Two categories together form most of the total.”
However, pie plots have limitations. When there are many categories, slices become too small and labels overlap, making the chart hard to read. Pie plots also make it difficult to compare close values, such as 22 percent versus 25 percent. In those cases, a bar chart is usually a better choice because it is easier to compare lengths than angles.
Good practices for pie plots include:
- Use them only when you have about 2 to 6 categories
- Combine very small categories into an “Others” group
- Display percentages clearly on the chart
- Keep category names short and readable
- Ensure the total represents a meaningful whole
In Matplotlib, you can create a plot using a list of values and labels. You can also show percentages on slices and slightly separate a slice if you want to highlight the most important category. Pie plots are best when you want a quick, simple view of composition and the data is not too complex.
