在Pandas中对DataFrame进行排序和切片

import pandas as pd

# 创建一个示例DataFrame
data = {'Name': ['Tom', 'Nick', 'John', 'Amy'],
        'Age': [20, 25, 30, 35],
        'City': ['New York', 'Paris', 'London', 'Tokyo']}
df = pd.DataFrame(data)

# 按照Age列的值进行升序排序
df_sorted = df.sort_values('Age')

print(df_sorted)

  Name  Age      City
0  Tom   20  New York
1 Nick   25     Paris
2 John   30    London
3  Amy   35     Tokyo

df_sorted = df.sort_values(['Age', 'Name'])

print(df_sorted)

  Name  Age      City
0  Tom   20  New York
1 Nick   25     Paris
2 John   30    London
3  Amy   35     Tokyo

# 使用loc属性选择前两行和所有列
df_slice = df.loc[:1, :]

print(df_slice)

  Name  Age      City
0  Tom   20  New York
1 Nick   25     Paris

# 使用iloc属性选择前两行和所有列
df_slice = df.iloc[:2, :]

print(df_slice)

  Name  Age      City
0  Tom   20  New York
1 Nick   25     Paris