通过索引从Pandas DataFrame访问单个值的简洁方法

import pandas as pd

# 创建一个示例DataFrame
data = {'Name': ['John', 'Emma', 'Mike'],
        'Age': [25, 28, 32],
        'City': ['New York', 'London', 'Paris']}
df = pd.DataFrame(data)

# 使用.at方法通过标签获取单个值
name = df.at[0, 'Name']
age = df.at[1, 'Age']
city = df.at[2, 'City']

# 使用.iat方法通过整数位置获取单个值
name_iat = df.iat[0, 0]
age_iat = df.iat[1, 1]
city_iat = df.iat[2, 2]

print(name)       # 输出: John
print(age)        # 输出: 28
print(city)       # 输出: Paris
print(name_iat)   # 输出: John
print(age_iat)    # 输出: 28
print(city_iat)   # 输出: Paris