Box Plot of a many Pandas Dataframes

Question

I have three dataframes containing 17 sets of data with groups A, B, and C. A shown in the following code snippet

import pandas as pd
import numpy as np
data         


        

Answer 1

Consider assigning an indicator like Location to distinguish your three sets of data. Then concatenate all three and melt the data to retrieve one value column, one Letter categorical column, and one Location column, all inputs into sns.boxplot:

import pandas as pd
import numpy as np
from matplotlib pyplot as plt
import seaborn as sns

data1 = pd.DataFrame(np.random.rand(17,3), columns=['A','B','C']).assign(Location=1)
data2 = pd.DataFrame(np.random.rand(17,3)+0.2, columns=['A','B','C']).assign(Location=2)
data3 = pd.DataFrame(np.random.rand(17,3)+0.4, columns=['A','B','C']).assign(Location=3)

cdf = pd.concat([data1, data2, data3])    
mdf = pd.melt(cdf, id_vars=['Location'], var_name=['Letter'])
print(mdf.head())

#    Location Letter     value
# 0         1      A  0.223565
# 1         1      A  0.515797
# 2         1      A  0.377588
# 3         1      A  0.687614
# 4         1      A  0.094116

ax = sns.boxplot(x="Location", y="value", hue="Letter", data=mdf)    
plt.show()