两个分类变量的描述性统计数据(熊猫)

需要 value_counts 对于一列或 groupby + size (或 count 如果需要省略 NaN s) :

a = df['Label'].value_counts()
print (a)
Cee    4
Bar    4
Foo    3
Name: Label, dtype: int64

#alternative
#a = df.groupby('Label').size()
print (a.mean())
3.6666666666666665

print (a.median())
4.0

a = df.groupby(['Label','Letter']).size()
print (a)
Label  Letter
Bar    A         1
       G         1
       N         1
       P         1
Cee    B         2
       C         1
       D         1
Foo    A         1
       B         1
       C         1
dtype: int64

print (a.mean())
1.1

print (a.median())
1.0