Hi, May be I misunderstood your question: dat<- read.table(text=" Date Time Var 1 1 2 1 1 4 1 1 5 1 2 8 1 2 8 1 2 9 2 1 3 2 1 4 2 1 4 ",sep="",header=TRUE) dat$UniqueID <- paste(dat$Date,dat$Time, sep = '_') aggregate(dat$Var,list(dat$UniqueID),sum) #isn't this the correct order # Group.1 x #1 1_1 11 #2 1_2 25 #3 2_1 11 library(plyr) ddply(dat,.(UniqueID),summarize,Var=sum(Var)) # UniqueID Var #1 1_1 11 #2 1_2 25 #3 2_1 11 A.K.
----- Original Message ----- From: Ye Lin <ye...@lbl.gov> To: R help <r-help@r-project.org> Cc: Sent: Wednesday, May 29, 2013 2:23 PM Subject: [R] combine two columns into one Hey all! I have a time series dataset like this: Date Time Var 1 1 2 1 1 4 1 1 5 1 2 8 1 2 8 1 2 9 2 1 3 2 1 4 2 1 4 I created a unique id for each row: dat$UniqueID <- paste(dat$Date,dat$Time, sep = '_') then aggregate(dat$Var, list(dat$UniqueID), sum) however the final output is not in ideal order I look for (I simply this example provided above).I would like to have order like this: 1_1 1_2 2_1 Thanks for your help! [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list 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 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.
