仅显示一个类别的求和函数值

Question

data = {'Person': ['a','b','c','d','a','b','c','d','b','c'],
        'months':['Jan','Jan','Jan','Jan','Feb','Feb','Feb','Feb','March','March'],
        'income':[100,75,80,56,48,56,37,48,95,65]}
df = pd.DataFrame(data)

df.groupby(['Person'])['income'].sum()

输出：

Person  
a    148  
b    226  
c    182  
d    104  
Name: income, dtype: int64

但是我只想显示a的数据。我该怎么办？

Answer 1

df[df['Person'] == 'a'].groupby(['Person'])['income'].sum()

输出

Person
a    148
Name: income, dtype: int64

Answer 2

如果只需要groupby，为什么要使用a？

df.loc[df["Person"].eq("a"),"income"].sum()

#148

Answer 3

您不需要groupby，只需使用eq和sum：

print(df.loc[df['Person'].eq('a'), 'income'].sum())

输出：

148