python - Best way to eliminate columns with only one value from pandas dataframe -

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i'm trying build function eliminate dataset columns 1 value. used function:

def onecatelimination(dataframe):     columns=dataframe.columns.values     column in columns:         if len(dataframe[column].value_counts().unique())==1:              del dataframe[column]         return dataframe

the problem function eliminates column more 1 distinct value, i.e. index column integer number..

just

df.dropna(thresh=2, axis=1)

will work. no need else. keep columns 2 or more non-na values (controlled value passed thresh). axis kwarg let work rows or columns. rows default, need pass axis=1 explicitly work on columns (i forgot @ time answered, hence edit). see dropna() more information.


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