Table of Contents
To add a line to a scatterplot in Seaborn, you can use the regplot() function, which accepts the x and y values of the scatterplot data to draw a linear regression line. You can also use the lmplot() function, which combines regplot() and FacetGrid to plot multiple regression lines, if needed. Additionally, you can adjust the line’s color, style, and other parameters using the various parameters available in Seaborn.
You can use the following methods to add a line to a scatter plot in seaborn:
Method 1: Add Horizontal Line
#add horizontal line at y=15 plt.axhline(y=15)
Method 2: Add Vertical Line
#add vertical line at x=4 plt.axvline(x=4)
Method 3: Add Custom Line
#add straight line that extends from (x,y) coordinates (2,0) to (6, 25) plt.plot([2, 6], [0, 25])
The following examples show how to use each method in practice.
Example 1: Add Horizontal Line to Seaborn Scatter Plot
The following code shows how to create a scatter plot in seaborn and add a horizontal line at y = 15:
import seaborn as sns
import matplotlib.pyplot as plt
#create DataFrame
df = pd.DataFrame({'x': [1, 2, 3, 4, 5, 6, 7, 8],
'y': [18, 22, 19, 14, 14, 11, 20, 28]})
#create scatterplot
sns.scatterplot(x=df.x, y=df.y)
#add horizontal line to scatterplot
plt.axhline(y=15)
Example 2: Add Vertical Line to Seaborn Scatter Plot
The following code shows how to create a scatter plot in seaborn and add a vertical line at x = 4:
import seaborn as sns
import matplotlib.pyplot as plt
#create DataFrame
df = pd.DataFrame({'x': [1, 2, 3, 4, 5, 6, 7, 8],
'y': [18, 22, 19, 14, 14, 11, 20, 28]})
#create scatterplot
sns.scatterplot(x=df.x, y=df.y)
#add vertical line to scatterplot
plt.axvline(x=4)
Example 3: Add Custom Line to Seaborn Scatter Plot
import seaborn as sns
import matplotlib.pyplot as plt
#create DataFrame
df = pd.DataFrame({'x': [1, 2, 3, 4, 5, 6, 7, 8],
'y': [18, 22, 19, 14, 14, 11, 20, 28]})
#create scatterplot
sns.scatterplot(x=df.x, y=df.y)
#add custom line to scatterplot
plt.plot([2, 6], [0, 25])
Note: You can find the complete documentation to the seaborn scatter() function .
The following tutorials explain how to perform other common tasks using seaborn: