根據python中年齡列的條件計算平均年齡

Question

我有一個R代碼，正在努力用python翻譯。 請幫忙

df$age[(df$age < 18)] <- mean(df$age[(df$age >= 18) & (df$age <=30)],na.rm=TRUE)

Answer 1

編輯：我在數據中添加None以獲取DataFrame NaN

---

大概

df.age[(df.age < 18)] = df.age[(df.age >= 18) & (df.age <= 30)].mean()

工作實例

import pandas as pd

data = {'age': [6, 4, 18, 21, 30, 45, None]}

df = pd.DataFrame(data)

print(df)
print('---')

df.age[(df.age < 18)] = df.age[(df.age >= 18) & (df.age <= 30)].mean()

print(df)
print('---')

結果

    age
0   6.0
1   4.0
2  18.0
3  21.0
4  30.0
5  45.0
6   NaN
---
    age
0  23.0
1  23.0
2  18.0
3  21.0
4  30.0
5  45.0
6   NaN
---