R: Splitting dataframe columnwise












1















I have a dataframe with the this structure



x = data.frame(let = letters, LET = LETTERS, num1 = 1:26, num2 = 21:46, num3 = 71:96, num4 = 68:93 )


I want to split it into list of 3 columns dataframes.The first two columns let and LET remains common, the third column varies. The first dataframe would be (let, LET, num1) and the second one would be (let, LET, num2) and so on so forth.



My current strategy is to convert the dataframe into long format and split it based on the num using plyr and dplyr packages. Is there an easier way to accomplish this task.










share|improve this question





























    1















    I have a dataframe with the this structure



    x = data.frame(let = letters, LET = LETTERS, num1 = 1:26, num2 = 21:46, num3 = 71:96, num4 = 68:93 )


    I want to split it into list of 3 columns dataframes.The first two columns let and LET remains common, the third column varies. The first dataframe would be (let, LET, num1) and the second one would be (let, LET, num2) and so on so forth.



    My current strategy is to convert the dataframe into long format and split it based on the num using plyr and dplyr packages. Is there an easier way to accomplish this task.










    share|improve this question



























      1












      1








      1








      I have a dataframe with the this structure



      x = data.frame(let = letters, LET = LETTERS, num1 = 1:26, num2 = 21:46, num3 = 71:96, num4 = 68:93 )


      I want to split it into list of 3 columns dataframes.The first two columns let and LET remains common, the third column varies. The first dataframe would be (let, LET, num1) and the second one would be (let, LET, num2) and so on so forth.



      My current strategy is to convert the dataframe into long format and split it based on the num using plyr and dplyr packages. Is there an easier way to accomplish this task.










      share|improve this question
















      I have a dataframe with the this structure



      x = data.frame(let = letters, LET = LETTERS, num1 = 1:26, num2 = 21:46, num3 = 71:96, num4 = 68:93 )


      I want to split it into list of 3 columns dataframes.The first two columns let and LET remains common, the third column varies. The first dataframe would be (let, LET, num1) and the second one would be (let, LET, num2) and so on so forth.



      My current strategy is to convert the dataframe into long format and split it based on the num using plyr and dplyr packages. Is there an easier way to accomplish this task.







      r split dataframe subset






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      share|improve this question













      share|improve this question




      share|improve this question








      edited Nov 16 '18 at 4:37









      Cœur

      19.1k9114155




      19.1k9114155










      asked Mar 12 '16 at 7:21









      ArihantArihant

      321618




      321618
























          2 Answers
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          2














          You can use lapply like so for your example



          lapply(1:4, function(D) x[ ,c("let", "LET", paste0("num", D))])


          If you don't know the column names of the num* columns you could use



          nonLetNames <- names(x)[!(names(x) %in% c("let", "LET"))]
          lapply(nonLetNames, function(nom) x[ ,c("let", "LET", nom)])





          share|improve this answer































            1














            Here is a Map based approach



            Map(function(x,y,z) setNames(cbind(x,y), c(names(x), z)), 
            list(x[1:2]), x[-(1:2)], names(x)[-(1:2)])





            share|improve this answer























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              2 Answers
              2






              active

              oldest

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              2 Answers
              2






              active

              oldest

              votes









              active

              oldest

              votes






              active

              oldest

              votes









              2














              You can use lapply like so for your example



              lapply(1:4, function(D) x[ ,c("let", "LET", paste0("num", D))])


              If you don't know the column names of the num* columns you could use



              nonLetNames <- names(x)[!(names(x) %in% c("let", "LET"))]
              lapply(nonLetNames, function(nom) x[ ,c("let", "LET", nom)])





              share|improve this answer




























                2














                You can use lapply like so for your example



                lapply(1:4, function(D) x[ ,c("let", "LET", paste0("num", D))])


                If you don't know the column names of the num* columns you could use



                nonLetNames <- names(x)[!(names(x) %in% c("let", "LET"))]
                lapply(nonLetNames, function(nom) x[ ,c("let", "LET", nom)])





                share|improve this answer


























                  2












                  2








                  2







                  You can use lapply like so for your example



                  lapply(1:4, function(D) x[ ,c("let", "LET", paste0("num", D))])


                  If you don't know the column names of the num* columns you could use



                  nonLetNames <- names(x)[!(names(x) %in% c("let", "LET"))]
                  lapply(nonLetNames, function(nom) x[ ,c("let", "LET", nom)])





                  share|improve this answer













                  You can use lapply like so for your example



                  lapply(1:4, function(D) x[ ,c("let", "LET", paste0("num", D))])


                  If you don't know the column names of the num* columns you could use



                  nonLetNames <- names(x)[!(names(x) %in% c("let", "LET"))]
                  lapply(nonLetNames, function(nom) x[ ,c("let", "LET", nom)])






                  share|improve this answer












                  share|improve this answer



                  share|improve this answer










                  answered Mar 12 '16 at 7:25









                  HughHugh

                  7,87543669




                  7,87543669

























                      1














                      Here is a Map based approach



                      Map(function(x,y,z) setNames(cbind(x,y), c(names(x), z)), 
                      list(x[1:2]), x[-(1:2)], names(x)[-(1:2)])





                      share|improve this answer




























                        1














                        Here is a Map based approach



                        Map(function(x,y,z) setNames(cbind(x,y), c(names(x), z)), 
                        list(x[1:2]), x[-(1:2)], names(x)[-(1:2)])





                        share|improve this answer


























                          1












                          1








                          1







                          Here is a Map based approach



                          Map(function(x,y,z) setNames(cbind(x,y), c(names(x), z)), 
                          list(x[1:2]), x[-(1:2)], names(x)[-(1:2)])





                          share|improve this answer













                          Here is a Map based approach



                          Map(function(x,y,z) setNames(cbind(x,y), c(names(x), z)), 
                          list(x[1:2]), x[-(1:2)], names(x)[-(1:2)])






                          share|improve this answer












                          share|improve this answer



                          share|improve this answer










                          answered Mar 12 '16 at 7:39









                          akrunakrun

                          416k13205278




                          416k13205278






























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