遍历DataFrame列中的值，如果满足条件，则更新所述值

import pandas as pd

data = {'A': [1, 2, 3, 4, 5], 'B': [6, 7, 8, 9, 10]}
df = pd.DataFrame(data)

for index, value in df['A'].items():
    if value > 3:
        df.at[index, 'A'] = value * 2

print(df)

    A   B
0   1   6
1   2   7
2   3   8
3   8   9
4  10  10