根据下图转换 pandas 数据框

Question

请帮助我了解在下图中转换 pandas DataFrame 的最佳方法。

dct = {'section': {0: 1, 1: 1, 2: 1, 3: 1, 4: 2, 5: 2, 6: 3, 7: 3, 8: 3},
 'friendly': {0: 5, 1: 5, 2: 5, 3: 4, 4: 3, 5: 1, 6: 2, 7: 5, 8: 5}}
df = pd.DataFrame(dct)

5：优秀 4：非常好 3：好 2：还好 1 : 差

输入：

输出：

Answer 1

将 crosstab for count, then get percentages to df2 by divide by sum, join by concat 与 keys 一起用于 MultiIndex，对其进行排序并在 map 中展平：

d = {5 : 'Excellent', 4 : 'Very Good', 3 : 'Good', 2 : 'Just Okay', 1 : 'Poor'}

df1 = pd.crosstab(df['section'], df['friendly'])
df2 = df1.div(df1.sum(axis=1), axis=0).mul(100).round().astype(int)

df = (pd.concat([df1, df2], keys=('Count','Per'), axis=1)
        .sort_index(axis=1, ascending=[False, True], level=[1,0])
        .rename(columns=d))

df.columns = df.columns.map(lambda x: f'{x[1]}_{x[0]}')
df = df.reset_index()
print (df)
   section  Excellent_Count  Excellent_Per  Very Good_Count  Very Good_Per  \
0        1                3             75                1             25   
1        2                0              0                0              0   
2        3                2             67                0              0   

   Good_Count  Good_Per  Just Okay_Count  Just Okay_Per  Poor_Count  Poor_Per  
0           0         0                0              0           0         0  
1           1        50                0              0           1        50  
2           0         0                1             33           0         0

根据下图转换 pandas 数据框

Transform pandas dataframe as per the image below

python

stack

pivot

unpivot

pandas