Enhancing Seaborn Pairplots: Adding Black Marker Borders

Seaborn’s Pairplot is a useful way for visualizing pairwise relationships in datasets. However, implementing changes to make certain data points stand out can make it much more useful. One common alteration is adding black borders around certain markers which can help you see important data points or groups in the plot.

In this post, we will understand and implement, adding black border around certain markers with help of examples.

Enhancing Seaborn Pairplots: Adding Black Marker Borders

  • Why Add black Borders Around Markers?
  • Methods for Implementing Black Borders Around Markers
    • Customizing marker styles: Using sns.pairplot with Hue Parameter
    • Creating a Custom Pairplot with Black Borders

Why Add black Borders Around Markers?

Black borders around markers in a Seaborn Pairplot can serve as visual cues to distinguish specific data points or groups from the rest of the dataset. This customization can be particularly useful when dealing with complex datasets containing multiple variables, making it easier to identify patterns or outliers. By outlining certain markers in black, you can effectively emphasize their significance within the context of the plot.

Methods for Implementing Black Borders Around Markers

There are majorly 2 techniques to implementing and enhancing visualization by adding Black Borders Around Certain Markers In A Seaborn Pairplot:

  • Using sns.pairplot with hue Parameter: Set the edgecolor parameter to ‘black’ within plot_kws to achieve black borders around markers representing a specific group, such as the ‘setosa’ species in the Iris dataset.
  • Creating a Custom Pairplot with Black Borders: By iterating through each subplot to identify markers representing a specific group, such as the ‘setosa’ species and setting the edge color of these markers to black, enhancing visual distinction and highlighting key data groups.

Customizing marker styles: Using sns.pairplot with Hue Parameter

This method involves setting the edgecolor parameter to ‘black’ within plot_kws to achieve black borders around markers representing a specific group, such as the ‘setosa’ species in the Iris dataset.

Python
import seaborn as sns
import matplotlib.pyplot as plt
iris = sns.load_dataset("iris")

# Create pairplot with black borders around markers for 'setosa'
sns.pairplot(iris, hue="species", markers=["o", "s", "D"],
             plot_kws={'edgecolor': 'black'})
plt.show()

Output:

Black Borders Around Markers

Creating a Custom Pairplot with Black Borders

This method involves creating a pairplot and then iterating through each axis to set black borders around markers specifically for a certain group, identified by a specific marker (e.g., ‘o’ for ‘setosa’).

In the code, the process of setting black borders for specific markers is accomplished as follows:

  • for ax in g.axes.flatten(): Iterates through each subplot (axis) in the pair plot.
  • for collection in ax.collections: Iterates through each collection of markers in the subplot.
  • if len(collection.get_offsets()) > 0 and collection.get_offsets()[0, 0] == iris[iris[‘species’] == ‘setosa’].iloc[0, 0]: Checks if the current collection of markers corresponds to the ‘setosa’ species.
  • collection.set_edgecolor(‘black’): Sets the edge color of the markers in the current collection to black.
Python
import seaborn as sns
import matplotlib.pyplot as plt
iris = sns.load_dataset("iris")

g = sns.pairplot(iris, hue="species", markers=["o", "s", "D"])
# Set black borders for specific markers
for ax in g.axes.flatten():
    for collection in ax.collections:
        if len(collection.get_offsets()) > 0 and collection.get_offsets()[0, 0] == iris[iris['species'] == 'setosa'].iloc[0, 0]:
            collection.set_edgecolor('black')

plt.show()

Output:

Black Borders using Custom Function

Note: All the visualizations are just the snapshot example for better and enhanced visualization.

Conclusion

Adding black borders around certain markers in a Seaborn Pairplot can greatly enhance the interpretability of the plot by emphasizing specific data points or groups. By following the provided code examples, users can easily customize their Pairplots to highlight relevant information, leading to better insights and understanding of the underlying data. Experimenting with different marker styles and color palettes can further enhance the visual appeal and effectiveness of the plot for data analysis and communication purposes.



Contact Us