Or, f3 <- function (dat1) { i <- dat1$Event_Occurence == 1 split(dat1$Week[i], dat1$ID[i]) }
in addition to the previously mentioned f1 <- function(dat1) { with(dat1,tapply(as.logical(Event_Occurence),ID,FUN=which )) } f2 <- function(dat1){ lapply(split(dat1,dat1$ID),function(x) which(!!x[,3])) } Bill Dunlap Spotfire, TIBCO Software wdunlap tibco.com > -----Original Message----- > From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On > Behalf > Of arun > Sent: Tuesday, November 12, 2013 2:13 PM > To: R help > Subject: Re: [R] Data transformation to list for event occurence > > > > Hi Anindya, > > You may try: > dat1 <- read.table(text="ID Week Event_Occurence > A 1 0 > A 2 0 > A 3 1 > A 4 0 > B 1 1 > B 2 0 > B 3 0 > B 4 1",sep="",header=TRUE,stringsAsFactors=FALSE) > > with(dat1,tapply(as.logical(Event_Occurence),ID,FUN=which )) > #or > lapply(split(dat1,dat1$ID),function(x) which(!!x[,3])) > A.K. > > > > > > On Tuesday, November 12, 2013 4:58 PM, Anindya Sankar Dey > <anindy...@gmail.com> > wrote: > Hi, > > Say I have a following data > > ID Week Event_Occurence > A 1 0 > A 2 0 > A 3 1 > A 4 0 > B 1 1 > B 2 0 > B 3 0 > B 4 1 > > that whether an individual experienced an event in a particular week. > > I wish to create list such as the first element of the list will be a > vector listing the week number when the event has occurred for A, followed > by that of B. > > Can you help creating this? > > -- > Anindya Sankar Dey > > [[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. ______________________________________________ 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.