KeyError inside a def function-CodePudding

I am transforming some data and I found myself in the situation where I needed to repeat the same process across different dataframes so I thought that building a function would be great.

I started doing this:


count_words = lambda x: len(x)
index = 'word_count'
values= ['Search term', 'Clicks', 'Impr.']

def table_transformation(dataframe, index, values):
    dataframe_to_pivot = pd.pivot_table(data= dataframe,
                                        index= index,
                                        values= values,
                                        aggfunc= {values[0]: count_words,
                                                  values[1]: np.sum,
                                                  values[2]: np.sum}
                                       )
    
    dataframe_to_pivot.sort_values(by=[index], ascending= True)
    sum_counts = dataframe_to_pivot.iloc[9:].sum()
    dataframe_to_pivot.drop(dataframe_to_pivot.index[9:].tolist())
    dataframe_to_pivot.loc[' 10'] = sum_counts
    return dataframe_to_pivot

fy21_word_counts = fy21.apply(table_transformation, args=(index, values))
fy21_word_counts

I got a KeyError: 'Search term' error.

What I tried:

I tried inserting the actual names of the columns inside the function but got the same error
the logic inside the function works outside the function's def() structure

What is it that I overlooked/ misunderstood?

Thank you for your time.

CodePudding user response：

Use DataFrame.pipe, because need pass DataFrame instead apply function for each column by .apply:

fy21_word_counts = fy21.pipe(table_transformation, index, values)