Pandas - 如何形成组然后根据两列为每个组绘制分布（条形图）？

Question

----| col_1 | col_2 | col_3 (...) row_1| "A" "Yes" "Yes" row_2| "B" "Yes" "No" row_3| "A" "Yes" "Yes" row_4| "A" "No" "Yes" ----| col_1 | col_2 | col_3 (...) row_1| "A" "Yes" "Yes" row_2| "B" "Yes" "No" row_3| "A" "Yes" "Yes" row_4| "A" "No" "Yes" Result for "A": 2 | 1 | | ("Yes", "Yes") ("No", "Yes") ("Yes", "No") ("No", "No") 2 | 1 | | ("Yes", "Yes") ("No", "Yes") ("Yes", "No") ("No", "No")

How do I group a pandas DataFrame in the above format by col_1 and create a barplot for each group which visualises the distribution (number of occurrences) of value pairs (col_2, col_3) ? Col_2 and col_3 have two distinct values which are "Yes" and "No" . The possible pairs would be ("Yes", "Yes") , ("Yes", "No") , ("No", "Yes") , ("No", "No") .

Thanks in advance!

Answer 1

import matplotlib.pyplot as plt

df = pd.DataFrame(
    [['A', 'Yes', 'Yes'],
    ['B', 'Yes', 'No'],
    ['A', 'Yes', 'Yes'],
    ['A', 'No', 'Yes']],

    columns= ['col_1', 'col_2', 'col_3']   
)

for key, grp in df.groupby(['col_2', 'col_3']):
    grp['col_1'].hist()
    plt.show()

You should see 3 plots -one for each col_2/col_3 pairing