How to Label Points in Pandas Scatter Plot


You can use the following basic syntax to label the points in a pandas scatter plot:

#create scatter plot of x vs. y
ax = df.plot(kind='scatter', x='x_var', y='y_var')

#label each point in scatter plot
for idx, row in df.iterrows():
    ax.annotate(row['label_var'], (row['x_var'], row['y_var']))

This particular example creates a scatter plot of the values in the columns x_var and y_var and then uses the values in the column called label_var as the labels for the points.

The following example shows how to use this syntax in practice.

Example: How to Label Points in Pandas Scatter Plot

Suppose we have the following pandas DataFrame that shows the points and assists for basketball players on various teams:

import pandas as pd

#create DataFrame
df = pd.DataFrame({'team': ['A', 'B', 'C', 'D', 'E', 'F', 'G', 'H'],
                   'assists': [3, 4, 4, 5, 5, 6, 7, 7],
                   'points': [7, 9, 14, 13, 10, 11, 12, 13]})

#view DataFrame
print(df)

  team  assists  points
0    A        3       7
1    B        4       9
2    C        4      14
3    D        5      13
4    E        5      10
5    F        6      11
6    G        7      12
7    H        7      13

We can use the following syntax to create a scatter plot of assists vs. points and use the values in the team column as labels:

#create scatter plot of assists vs. points
ax = df.plot(kind='scatter', x='assists', y='points')

#label each point in scatter plot
for idx, row in df.iterrows():
    ax.annotate(row['team'], (row['assists'], row['points']))

Notice that each of the points in the plot have a label that tells us which team each player is on.

Note that we can also use the following arguments in the annotate() function to modify the appearance of the text labels:

  • xytext: The coordinates to use to offset the text
  • textcoords: How to offset the text
  • family: The font family to use for the text
  • fontsize: The font size to use for the text

The following code shows how to use these arguments in practice to modify the appearance of the text labels:

#create scatter plot of assists vs. points
ax = df.plot(kind='scatter', x='assists', y='points')

#add custom label to each point in scatter plot
for idx, row in df.iterrows():
    ax.annotate(row['team'], (row['assists'], row['points']), xytext=(5,-5),
                textcoords='offset points', family='sans-serif', fontsize=12)

label points in pandas scatter plot

Notice how the labels are now offset from the points so they’re easier to read, they have a larger font size, and use sans-serif as the font family to make them more aesthetically pleasing.

Feel free to play around with the arguments in the annotate() function to create text labels that appear however you’d like.

Additional Resources

The following tutorials explain how to perform other common tasks in pandas:

How to Plot Histograms by Group in Pandas
How to Plot Distribution of Column Values in Pandas
How to Create Scatter Plot Using Multiple Columns in Pandas

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