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pythonlistpandasdataframedata-analysis

How to convert my dataframe to a 2d list with all column as a list

I have a df,

Name  Class
Sri   A
Ram   B

My expected output is 

 [["Name","Sri","Ram"],["Class","A","B"]]

I tried df.values.tolist() but gives row wise lists, I need it in column wise. Thanks in advance

Solution

  • Use transpose:

    print (df.values.T.tolist())
[['Sri', 'Ram'], ['A', 'B']]

    If need also columns names first transpose by T with reset_index:

    print (df.T.reset_index().values.tolist())
[['Name', 'Sri', 'Ram'], ['Class', 'A', 'B']]

    EDIT: For remove NaNs use list comprehension:

    print (df)
  Name Class
0  Sri     A
1  Ram   NaN

L = df.values.T.tolist()
print (L)
[['Sri', 'Ram'], ['A', nan]]

L1 = [[i for i in x if pd.notnull(i)] for x in L]
print (L1)
[['Sri', 'Ram'], ['A']]