Sorting, Ranking, and Reindexing
Data rarely comes in the perfect order for analysis — that’s where sorting and reindexing come in. Whether you want to sort by column values or change row order manually, Pandas makes it simple.
Sorting Values
You can sort a DataFrame based on one or more columns using .sort_values()
.
Sort by Score
df.sort_values(by="Score", ascending=False)
This helps you find top performers, earliest dates, or lowest prices.
Ranking Data
To rank values, use .rank()
. It assigns a rank number to each value, handling ties gracefully.
Rank Scores
df["Score"].rank(ascending=False)
This is great for leaderboards or percentile-based groupings.
Reindexing Rows
Reindexing lets you reset or customize the order of your DataFrame’s rows with .reindex()
.
Reorder Rows by Index
df.reindex([2, 0, 1])
Use this when aligning datasets or creating custom views.
Summary Table
Feature | Method | Purpose |
---|---|---|
Sort Rows | sort_values() | Order rows by column values |
Assign Rankings | rank() | Give rank numbers to values |
Reorder Rows | reindex() | Set a custom row index order |
What’s Next?
You’ll now work with missing and duplicate data to keep your datasets clean and reliable.