Python Pandas - 使用 MultiIndex 中的级别名称仅设置一个新的特定级别
要使用MultiIndex中的级别名称仅设置一个新的特定级别,请使用该方法。参数level用于设置级别名称。MultiIndex.set_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 = [[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。我们使用“level”参数中的级别名称设置了一个新的单个特定级别-
print("\nSet a new level in Multi-index...\n",multiIndex.set_levels(['Emma', 'Angelina', 'Scarlett', 'Jeni'], level = 'student'))
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) #setthelevelinMultiIndex # We have set a new single specific level using the level name in the "level" parameter print("\nSet a new level in Multi-index...\n",multiIndex.set_levels(['Emma', 'Angelina', 'Scarlett', 'Jeni'], level = 'student'))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 a new level in Multi-index... MultiIndex([(1, 'Scarlett'), (2, 'Jeni'), (3, 'Angelina'), (4, 'Emma')], names=['ranks', 'student'])