Add Missing Date Index with default values












1















I have a pandas dataframe with an index representing the data (in monthly format) and multiple columns with numeric data. Min Example is below:



 dict1 = [{'var0': 45, 'var1': 3, 'var2': 2},
{'var0': 32, 'var1': 4, 'var2': 4},
{'var0': 23, 'var1': 5, 'var2': 8},
{'var0': 22, 'var1': 2, 'var2': 12},]
df = pd.DataFrame(dict1, index=['2016-08', '2016-09','2016-11','2016-12'])


Some of the months are missing however, that is, notice how the index jumps from Sep to Nov. I would like to fill all of the missing months such that the new dataframe contains additional rows with that month as an index and zeros in the respective row, that is:



  dict1 = [{'var0': 45, 'var1': 3, 'var2': 2},
{'var0': 32, 'var1': 4, 'var2': 4},
{'var0': 23, 'var1': 5, 'var2': 8},
{'var0': 0, 'var1': 0, 'var2': 0},
{'var0': 22, 'var1': 2, 'var2': 12},]
df = pd.DataFrame(dict1, index=['2016-08'', '2016-09', '2016-09','2016-11','2016-12'])


Can anyone recommend an approach?










share|improve this question





























    1















    I have a pandas dataframe with an index representing the data (in monthly format) and multiple columns with numeric data. Min Example is below:



     dict1 = [{'var0': 45, 'var1': 3, 'var2': 2},
    {'var0': 32, 'var1': 4, 'var2': 4},
    {'var0': 23, 'var1': 5, 'var2': 8},
    {'var0': 22, 'var1': 2, 'var2': 12},]
    df = pd.DataFrame(dict1, index=['2016-08', '2016-09','2016-11','2016-12'])


    Some of the months are missing however, that is, notice how the index jumps from Sep to Nov. I would like to fill all of the missing months such that the new dataframe contains additional rows with that month as an index and zeros in the respective row, that is:



      dict1 = [{'var0': 45, 'var1': 3, 'var2': 2},
    {'var0': 32, 'var1': 4, 'var2': 4},
    {'var0': 23, 'var1': 5, 'var2': 8},
    {'var0': 0, 'var1': 0, 'var2': 0},
    {'var0': 22, 'var1': 2, 'var2': 12},]
    df = pd.DataFrame(dict1, index=['2016-08'', '2016-09', '2016-09','2016-11','2016-12'])


    Can anyone recommend an approach?










    share|improve this question



























      1












      1








      1








      I have a pandas dataframe with an index representing the data (in monthly format) and multiple columns with numeric data. Min Example is below:



       dict1 = [{'var0': 45, 'var1': 3, 'var2': 2},
      {'var0': 32, 'var1': 4, 'var2': 4},
      {'var0': 23, 'var1': 5, 'var2': 8},
      {'var0': 22, 'var1': 2, 'var2': 12},]
      df = pd.DataFrame(dict1, index=['2016-08', '2016-09','2016-11','2016-12'])


      Some of the months are missing however, that is, notice how the index jumps from Sep to Nov. I would like to fill all of the missing months such that the new dataframe contains additional rows with that month as an index and zeros in the respective row, that is:



        dict1 = [{'var0': 45, 'var1': 3, 'var2': 2},
      {'var0': 32, 'var1': 4, 'var2': 4},
      {'var0': 23, 'var1': 5, 'var2': 8},
      {'var0': 0, 'var1': 0, 'var2': 0},
      {'var0': 22, 'var1': 2, 'var2': 12},]
      df = pd.DataFrame(dict1, index=['2016-08'', '2016-09', '2016-09','2016-11','2016-12'])


      Can anyone recommend an approach?










      share|improve this question
















      I have a pandas dataframe with an index representing the data (in monthly format) and multiple columns with numeric data. Min Example is below:



       dict1 = [{'var0': 45, 'var1': 3, 'var2': 2},
      {'var0': 32, 'var1': 4, 'var2': 4},
      {'var0': 23, 'var1': 5, 'var2': 8},
      {'var0': 22, 'var1': 2, 'var2': 12},]
      df = pd.DataFrame(dict1, index=['2016-08', '2016-09','2016-11','2016-12'])


      Some of the months are missing however, that is, notice how the index jumps from Sep to Nov. I would like to fill all of the missing months such that the new dataframe contains additional rows with that month as an index and zeros in the respective row, that is:



        dict1 = [{'var0': 45, 'var1': 3, 'var2': 2},
      {'var0': 32, 'var1': 4, 'var2': 4},
      {'var0': 23, 'var1': 5, 'var2': 8},
      {'var0': 0, 'var1': 0, 'var2': 0},
      {'var0': 22, 'var1': 2, 'var2': 12},]
      df = pd.DataFrame(dict1, index=['2016-08'', '2016-09', '2016-09','2016-11','2016-12'])


      Can anyone recommend an approach?







      python pandas date






      share|improve this question















      share|improve this question













      share|improve this question




      share|improve this question








      edited Nov 28 '18 at 19:17







      Tartaglia

















      asked Nov 28 '18 at 6:35









      TartagliaTartaglia

      909




      909
























          1 Answer
          1






          active

          oldest

          votes


















          2














          Create DatetimeIndex and use DataFrame.asfreq:



          df.index = pd.to_datetime(df.index)
          df = df.asfreq('MS', fill_value=0)


          Or DataFrame.reindex with pandas.date_range:



          df = df.reindex(pd.date_range(df.index.min(), df.index.max(), freq='MS'), fill_value=0)

          print(df)
          var0 var1 var2
          2016-08-01 45 3 2
          2016-09-01 32 4 4
          2016-10-01 0 0 0
          2016-11-01 23 5 8
          2016-12-01 22 2 12


          Solution with month period - creating DatetimeIndex.to_period with pandas.period_range:



          df.index = pd.to_datetime(df.index).to_period('M')
          df = df.reindex(pd.period_range(df.index.min(), df.index.max(), freq='M'), fill_value=0)
          print(df)
          var0 var1 var2
          2016-08 45 3 2
          2016-09 32 4 4
          2016-10 0 0 0
          2016-11 23 5 8
          2016-12 22 2 12


          Last if necessary convert to strings YY-MM add DatetimeIndex.strftime:



          df.index = df.index.strftime('%Y-%m')
          print(df)
          var0 var1 var2
          2016-08 45 3 2
          2016-09 32 4 4
          2016-10 0 0 0
          2016-11 23 5 8
          2016-12 22 2 12





          share|improve this answer





















          • 1





            Perfect, thank you so much!! Thanks also for the multiple approaches, will add that to my cheat sheet.

            – Tartaglia
            Nov 28 '18 at 19:19











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          1 Answer
          1






          active

          oldest

          votes








          1 Answer
          1






          active

          oldest

          votes









          active

          oldest

          votes






          active

          oldest

          votes









          2














          Create DatetimeIndex and use DataFrame.asfreq:



          df.index = pd.to_datetime(df.index)
          df = df.asfreq('MS', fill_value=0)


          Or DataFrame.reindex with pandas.date_range:



          df = df.reindex(pd.date_range(df.index.min(), df.index.max(), freq='MS'), fill_value=0)

          print(df)
          var0 var1 var2
          2016-08-01 45 3 2
          2016-09-01 32 4 4
          2016-10-01 0 0 0
          2016-11-01 23 5 8
          2016-12-01 22 2 12


          Solution with month period - creating DatetimeIndex.to_period with pandas.period_range:



          df.index = pd.to_datetime(df.index).to_period('M')
          df = df.reindex(pd.period_range(df.index.min(), df.index.max(), freq='M'), fill_value=0)
          print(df)
          var0 var1 var2
          2016-08 45 3 2
          2016-09 32 4 4
          2016-10 0 0 0
          2016-11 23 5 8
          2016-12 22 2 12


          Last if necessary convert to strings YY-MM add DatetimeIndex.strftime:



          df.index = df.index.strftime('%Y-%m')
          print(df)
          var0 var1 var2
          2016-08 45 3 2
          2016-09 32 4 4
          2016-10 0 0 0
          2016-11 23 5 8
          2016-12 22 2 12





          share|improve this answer





















          • 1





            Perfect, thank you so much!! Thanks also for the multiple approaches, will add that to my cheat sheet.

            – Tartaglia
            Nov 28 '18 at 19:19
















          2














          Create DatetimeIndex and use DataFrame.asfreq:



          df.index = pd.to_datetime(df.index)
          df = df.asfreq('MS', fill_value=0)


          Or DataFrame.reindex with pandas.date_range:



          df = df.reindex(pd.date_range(df.index.min(), df.index.max(), freq='MS'), fill_value=0)

          print(df)
          var0 var1 var2
          2016-08-01 45 3 2
          2016-09-01 32 4 4
          2016-10-01 0 0 0
          2016-11-01 23 5 8
          2016-12-01 22 2 12


          Solution with month period - creating DatetimeIndex.to_period with pandas.period_range:



          df.index = pd.to_datetime(df.index).to_period('M')
          df = df.reindex(pd.period_range(df.index.min(), df.index.max(), freq='M'), fill_value=0)
          print(df)
          var0 var1 var2
          2016-08 45 3 2
          2016-09 32 4 4
          2016-10 0 0 0
          2016-11 23 5 8
          2016-12 22 2 12


          Last if necessary convert to strings YY-MM add DatetimeIndex.strftime:



          df.index = df.index.strftime('%Y-%m')
          print(df)
          var0 var1 var2
          2016-08 45 3 2
          2016-09 32 4 4
          2016-10 0 0 0
          2016-11 23 5 8
          2016-12 22 2 12





          share|improve this answer





















          • 1





            Perfect, thank you so much!! Thanks also for the multiple approaches, will add that to my cheat sheet.

            – Tartaglia
            Nov 28 '18 at 19:19














          2












          2








          2







          Create DatetimeIndex and use DataFrame.asfreq:



          df.index = pd.to_datetime(df.index)
          df = df.asfreq('MS', fill_value=0)


          Or DataFrame.reindex with pandas.date_range:



          df = df.reindex(pd.date_range(df.index.min(), df.index.max(), freq='MS'), fill_value=0)

          print(df)
          var0 var1 var2
          2016-08-01 45 3 2
          2016-09-01 32 4 4
          2016-10-01 0 0 0
          2016-11-01 23 5 8
          2016-12-01 22 2 12


          Solution with month period - creating DatetimeIndex.to_period with pandas.period_range:



          df.index = pd.to_datetime(df.index).to_period('M')
          df = df.reindex(pd.period_range(df.index.min(), df.index.max(), freq='M'), fill_value=0)
          print(df)
          var0 var1 var2
          2016-08 45 3 2
          2016-09 32 4 4
          2016-10 0 0 0
          2016-11 23 5 8
          2016-12 22 2 12


          Last if necessary convert to strings YY-MM add DatetimeIndex.strftime:



          df.index = df.index.strftime('%Y-%m')
          print(df)
          var0 var1 var2
          2016-08 45 3 2
          2016-09 32 4 4
          2016-10 0 0 0
          2016-11 23 5 8
          2016-12 22 2 12





          share|improve this answer















          Create DatetimeIndex and use DataFrame.asfreq:



          df.index = pd.to_datetime(df.index)
          df = df.asfreq('MS', fill_value=0)


          Or DataFrame.reindex with pandas.date_range:



          df = df.reindex(pd.date_range(df.index.min(), df.index.max(), freq='MS'), fill_value=0)

          print(df)
          var0 var1 var2
          2016-08-01 45 3 2
          2016-09-01 32 4 4
          2016-10-01 0 0 0
          2016-11-01 23 5 8
          2016-12-01 22 2 12


          Solution with month period - creating DatetimeIndex.to_period with pandas.period_range:



          df.index = pd.to_datetime(df.index).to_period('M')
          df = df.reindex(pd.period_range(df.index.min(), df.index.max(), freq='M'), fill_value=0)
          print(df)
          var0 var1 var2
          2016-08 45 3 2
          2016-09 32 4 4
          2016-10 0 0 0
          2016-11 23 5 8
          2016-12 22 2 12


          Last if necessary convert to strings YY-MM add DatetimeIndex.strftime:



          df.index = df.index.strftime('%Y-%m')
          print(df)
          var0 var1 var2
          2016-08 45 3 2
          2016-09 32 4 4
          2016-10 0 0 0
          2016-11 23 5 8
          2016-12 22 2 12






          share|improve this answer














          share|improve this answer



          share|improve this answer








          edited Nov 28 '18 at 6:43

























          answered Nov 28 '18 at 6:37









          jezraeljezrael

          348k25304379




          348k25304379








          • 1





            Perfect, thank you so much!! Thanks also for the multiple approaches, will add that to my cheat sheet.

            – Tartaglia
            Nov 28 '18 at 19:19














          • 1





            Perfect, thank you so much!! Thanks also for the multiple approaches, will add that to my cheat sheet.

            – Tartaglia
            Nov 28 '18 at 19:19








          1




          1





          Perfect, thank you so much!! Thanks also for the multiple approaches, will add that to my cheat sheet.

          – Tartaglia
          Nov 28 '18 at 19:19





          Perfect, thank you so much!! Thanks also for the multiple approaches, will add that to my cheat sheet.

          – Tartaglia
          Nov 28 '18 at 19:19




















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