Python, Merging rows with same value in one column
问题 My dataframe looks like this: ID Class 0 9 1 8 1 6 2 6 2 2 3 15 3 1 3 8 What I would like to do is merging rows with same ID value in a way below: ID Class1 Class2 Class3 0 9 1 8 6 2 6 2 3 15 1 8 So for each ID which exists more than once, I want to create new column(s) and move values from rows to those columns. What is the fastest way to do this? I tried using groupby but it didn't give me appriopate results. 回答1: Use set_index with cumcount for new columns, reshape by unstack and last