Python Pandas - 在 MultiIndex 中设置级别
要在MultiIndex中设置级别，请使用Pandas中的方法。首先，导入所需的库-MultiIndex.set_levels()
import pandas as pd
MultiIndex是Pandas对象的多级或分层索引对象。创建数组：
arrays = [[1, 2, 3, 4], ['John', 'Tim', 'Jacob', 'Chris']]
“names”参数设置每个索引级别的名称。将from_arrays()被用来创建一个多指标-
multiIndex = pd.MultiIndex.from_arrays(arrays, names=('ranks', 'student'))在MultiIndex中设置级别-
print("\nSet new levels in Multi-index...\n",multiIndex.set_levels([['p', 'q', 'r', 's'], [10, 20, 30, 40]]))示例
以下是代码-
import pandas as pd
#MultiIndexisamulti-level,orhierarchical,indexobjectforpandasobjects
#Createarrays
arrays = [[1, 2, 3, 4], ['John', 'Tim', 'Jacob', 'Chris']]
# The "names" parameter sets the names for each of the index levels
#Thefrom_arrays()isusedtocreateaMultiIndex
multiIndex = pd.MultiIndex.from_arrays(arrays, names=('ranks', 'student'))
#displaytheMultiIndex
print("The Multi-index...\n",multiIndex)
#getthelevelsinMultiIndex
print("\nThe levels in Multi-index...\n",multiIndex.levels)
#setthelevelsinMultiIndex
print("\nSet new levels in Multi-index...\n",multiIndex.set_levels([['p', 'q', 'r', 's'], [10, 20, 30, 40]]))输出结果这将产生以下输出-
The Multi-index...
MultiIndex([(1, 'John'),
(2, 'Tim'),
(3, 'Jacob'),
(4, 'Chris')],
names=['ranks', 'student'])
The levels in Multi-index...
[[1, 2, 3, 4], ['Chris', 'Jacob', 'John', 'Tim']]
Set new levels in Multi-index...
MultiIndex([('p', 30),
('q', 40),
('r', 20),
('s', 10)],
names=['ranks', 'student'])