Hi Allaisone, If you want a data frame as the output you will have to put up with a few NA values unless each Customer has the same number of diet types:
a1df<-read.table(text="CustomerID DietType 1 a 1 c 1 b 2 f 2 a 3 j 4 c 4 c 4 f", header=TRUE,stringsAsFactors=FALSE) library(prettyR) stretch_df(a1df,"CustomerID","DietType") CustomerID DietType_1 DietType_2 DietType_3 1 1 a c b 2 2 f a <NA> 3 3 j <NA> <NA> 4 4 c c f Jim On Sun, Feb 25, 2018 at 11:59 PM, Allaisone 1 <allaiso...@hotmail.com> wrote: > Hi All > > I have a datafram which looks like this : > > CustomerID DietType > 1 a > 1 c > 1 b > 2 f > 2 a > 3 j > 4 c > 4 c > 4 f > > And I would like to reshape this so I can see the list of DietTypes per > customer in rows instead of columns like this : > >> MyDf > CustomerID DietType DietType DietType > 1 a c b > 2 f a > 3 j > 4 c c f > > I tried many times using melt(),spread (),and dcast () functions but was not > able to produce the desired table. The best attempt was by typing : > > # 1) Adding new column with unique values: > MyDf $newcol <- c (1:9) > #2) then : > NewDf <- dcast (MyDf,CustomerID~newcol,value.var=DietType) > > This produces the desired table but with many NA values like this : > > CustomerID 1 2 3 4 5 6 7 8 9 > 1 a c b NA NA NA NA NA NA > 2 NA NA NA f a NA NA NA NA > 3 NA NA NA NA NA j NA NA NA > 4 NA NA NA NA NA NA c c f > > As you see, the lette/s indicating DietType move to the right side each > time we move down leaving many NA values and as my original files is very > large, I expect that the final output would contain around 800,000 columns > and 70,000 rows. This is why my code works with small data but does not work > with my large file because of memory issue even though I'm using large PC. > > What changes I need to do with my code to produce the desired table where the > list of DietTypes are grouped in rows exactly like the second table shown > abover? > > Regards > Allaisnoe > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
