python - After groupby and apply function, output column names missing

Question

I was applying functions by subgroups to a data frame

output = mydf.groupby(['a','b','c']).apply(function)

In the output display, columns a,b and c column names are at a lower level compared to model output values, and when i list output, the column a,b,c are not shown in result.

list(output.columns)

I tried to set as_index = False at dataframe when apply the function but still doesn't work. What i'm missing here?

Thanks.

question from:https://stackoverflow.com/questions/66053341/after-groupby-and-apply-function-output-column-names-missing

Answer 1

reset_index() worked.

output = mydf.groupby(['a','b','c']).apply(function).reset_index()

solved my problem