Python Pandas - 当多索引中的所有级别均为 NaN 时删除该值

要在Multi-index中的所有级别均为NaN时删除该值，请使用该方法。设置参数how与valueall。multiIndex.dropna()

首先，导入所需的库——

import pandas as pd import numpy as np

创建一个包含所有NaN值的多索引。names参数设置索引中级别的名称-

multiIndex = pd.MultiIndex.from_arrays([[np.nan, np.nan], [np.nan, np.nan]], names=[a, b])

当Multi-index中的所有级别iareNaN时删除该值。对于所有NaN值，dropna()如果的“how”参数dropna()设置为“all”，则将删除所有值-

print("\nDropping the values when all levels are NaN...\n",multiIndex.dropna(how=all))

示例

以下是代码-

import pandas as pd import numpy as np #Createamulti-indexwithallNaNvalues #Thenamesparametersetsthenamesforthelevelsintheindex multiIndex = pd.MultiIndex.from_arrays([[np.nan, np.nan], [np.nan, np.nan]], names=[a, b]) #displaythemulti-index print("Multi-index...\n", multiIndex) #DropthevaluewhenalllevelsiareNaNinaMulti-index #WithallNaNvalues,thedropna()willdropallthevalues,ifthe # "how" parameter of the dropna() is set "all" print("\nDropping the values when all levels are NaN...\n",multiIndex.dropna(how=all))输出结果

这将产生以下输出-

Multi-index... MultiIndex([(nan, nan),(nan, nan)],names=[a, b]) Dropping the values when all levels are NaN... MultiIndex([], names=[a, b])