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seaborn distplot / displot with multiple distributions


I am using seaborn to plot a distribution plot. I would like to plot multiple distributions on the same plot in different colors:

Here's how I start the distribution plot:

import numpy as np
import pandas as pd
from sklearn.datasets import load_iris
iris = load_iris()
iris = pd.DataFrame(data= np.c_[iris['data'], iris['target']],columns= iris['feature_names'] + ['target'])

   sepal length (cm)  sepal width (cm)  petal length (cm)  petal width (cm)  target
0                5.1               3.5                1.4               0.2     0.0
1                4.9               3.0                1.4               0.2     0.0
2                4.7               3.2                1.3               0.2     0.0
3                4.6               3.1                1.5               0.2     0.0
4                5.0               3.6                1.4               0.2     0.0

sns.distplot(iris[['sepal length (cm)']], hist=False, rug=True);

enter image description here

The 'target' column contains 3 values: 0, 1, 2.

I would like to see one distribution plot for sepal length, where target ==0, target ==1, and target ==2, for a total of 3 plots.


Solution

  • The important thing is to sort the dataframe by values where target is 0, 1, or 2.

    import numpy as np
    import pandas as pd
    from sklearn.datasets import load_iris
    import seaborn as sns
    
    iris = load_iris()
    iris = pd.DataFrame(data=np.c_[iris['data'], iris['target']],
                        columns=iris['feature_names'] + ['target'])
    
    # Sort the dataframe by target
    target_0 = iris.loc[iris['target'] == 0]
    target_1 = iris.loc[iris['target'] == 1]
    target_2 = iris.loc[iris['target'] == 2]
    
    sns.distplot(target_0[['sepal length (cm)']], hist=False, rug=True)
    sns.distplot(target_1[['sepal length (cm)']], hist=False, rug=True)
    sns.distplot(target_2[['sepal length (cm)']], hist=False, rug=True)
    
    plt.show()
    

    The output looks like:

    enter image description here

    If you don't know how many values target may have, find the unique values in the target column, then slice the dataframe and add to the plot appropriately.

    import numpy as np
    import pandas as pd
    from sklearn.datasets import load_iris
    import seaborn as sns
    
    iris = load_iris()
    iris = pd.DataFrame(data=np.c_[iris['data'], iris['target']],
                        columns=iris['feature_names'] + ['target'])
    
    unique_vals = iris['target'].unique()  # [0, 1, 2]
    
    # Sort the dataframe by target
    # Use a list comprehension to create list of sliced dataframes
    targets = [iris.loc[iris['target'] == val] for val in unique_vals]
    
    # Iterate through list and plot the sliced dataframe
    for target in targets:
        sns.distplot(target[['sepal length (cm)']], hist=False, rug=True)