Python Pandas - 从 Multiindex 中的特定级别获取值

要从Multiindex中的特定级别获取值，请使用Pandas中的方法。multiIndex.get_level_values()

首先，导入所需的库-

import pandas as pd

创建多索引。names参数设置索引中级别的名称

multiIndex = pd.MultiIndex.from_arrays([[5, 10], [15, 20], [25, 30], [35, 40]], names=[a, b, c, d])

从特定值中获取值。获取第0级值-

print("\nGet level value (0th level)...\n",multiIndex.get_level_values(0))

获取1日电平值-

print("\nGet level value (1st level)...\n",multiIndex.get_level_values(1))

示例

以下是代码-

import pandas as pd #Createamulti-index #Thenamesparametersetsthenamesforthelevelsintheindex multiIndex = pd.MultiIndex.from_arrays([[5, 10], [15, 20], [25, 30], [35, 40]], names=[a, b, c, d]) print("Multi-index...\n",multiIndex) #get0thlevelvalue print("\nGet level value (0th level)...\n",multiIndex.get_level_values(0)) #get1stlevelvalue print("\nGet level value (1st level)...\n",multiIndex.get_level_values(1)) #droppingalevelfromthemultiindex print("\nDropping a level...\n",multiIndex.droplevel())输出结果

这将产生以下输出-

Multi-index... MultiIndex([( 5, 15, 25, 35), (10, 20, 30, 40)], names=[a, b, c, d]) Get level value (0th level)... Int64Index([5, 10], dtype=int64, name=a) Get level value (1st level)... Int64Index([15, 20], dtype=int64, name=b) Dropping a level... MultiIndex([(15, 25, 35), (20, 30, 40)], names=[b, c, d])