Python Pandas - 重新排列 MultiIndex 中的级别
要重新排列MultiIndex中的级别，请使用Pandas中的方法。使用order参数设置级别的顺序。MultiIndex.reorder_levels()
首先，导入所需的库-
import pandas as pd
MultiIndex是Pandas对象的多级或分层索引对象。创建数组-
arrays = [[2, 4, 3, 1], ['Peter', 'Chris', 'Andy', 'Jacob'], [50, 30, 40, 70]]
“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=('rank', 'student', 'points'))重新排序MultiIndex的级别。"order"参数用于在表单中设置级别以重新排序级别
print("\nReorder levels in MultiIndex...\n",multiIndex.reorder_levels(order=[2, 0, 1]))示例
以下是代码-
import pandas as pd
#MultiIndexisamulti-level,orhierarchical,indexobjectforpandasobjects
#Createarrays
arrays = [[2, 4, 3, 1], ['Peter', 'Chris', 'Andy', 'Jacob'], [50, 30, 40, 70]]
# The "names" parameter sets the names for each of the index levels
#Thefrom_arrays()isusedtocreateaMultiIndex
multiIndex = pd.MultiIndex.from_arrays(arrays, names=('rank', 'student', 'points'))
#displaytheMultiIndex
print("The MultiIndex...\n",multiIndex)
#getthelevelsinMultiIndex
print("\nThe levels in MultiIndex...\n",multiIndex.levels)
#ReorderlevelsofMultiIndex
# The "order" parameter is used to set the level in a form to reorder levels
print("\nReorder levels in MultiIndex...\n",multiIndex.reorder_levels(order=[2, 0, 1]))输出结果这将产生以下输出-
The MultiIndex...
MultiIndex([(2, 'Peter', 50),
(4, 'Chris', 30),
(3, 'Andy', 40),
(1, 'Jacob', 70)],
names=['rank', 'student', 'points'])
The levels in MultiIndex...
[[1, 2, 3, 4], ['Andy', 'Chris', 'Jacob', 'Peter'], [30, 40, 50, 70]]
Reorder levels in MultiIndex...
MultiIndex([(50, 2, 'Peter'),
(30, 4, 'Chris'),
(40, 3, 'Andy'),
(70, 1, 'Jacob')],
names=['points', 'rank', 'student'])