Pandas:迭代现有列并基于条件创建新列

import pandas as pd

# 创建一个DataFrame
data = {'Name': ['Tom', 'Nick', 'John', 'Alice'],
        'Age': [20, 25, 30, 35],
        'Gender': ['Male', 'Male', 'Male', 'Female']}
df = pd.DataFrame(data)

# 迭代现有列并基于条件创建新列
df['NewColumn'] = ''
for index, row in df.iterrows():
    if row['Age'] < 30:
        df.at[index, 'NewColumn'] = 'Young'
    else:
        df.at[index, 'NewColumn'] = 'Old'

# 打印DataFrame
print(df)

   Name  Age  Gender NewColumn
0   Tom   20    Male     Young
1  Nick   25    Male     Young
2  John   30    Male       Old
3 Alice   35  Female       Old