# here's an example data frame n <- 10 mydf <- data.frame(present=rnorm(n), answer=sample(1:4, n, replace=TRUE), p.num=sample(1:18, n, replace=TRUE), session=sample(1:2, n, replace=TRUE), count=sample(1:8, n, replace=TRUE), type=sample(1:3, n, replace=TRUE))
# define a new variable, combo5, that represents the combination of the five columns you specified mydf$combo5 <- with(mydf, interaction(answer, p.num, session, count, type, drop=TRUE)) # split the data frame according to combo5 # this gives you a list of data frames mydf.split <- split(mydf, mydf$combo5) # use lapply() and write.table() to write each date frame in the list to a file lapply(mydf.split, function(x) write.table(x, file=as.character(x$combo5[1]), sep="\t", col.names=F, row.names=F)) Jean On Sat, Apr 6, 2013 at 6:07 PM, Mansfield, Desmond <dcm...@exeter.ac.uk>wrote: > Hello Everybody, > > I'm working with a dataframe that has 18 columns. I would like to subset > the data in one of these columns, "present", according to combinations of > data in six of the other columns within the data frame and then save this > into a text file. The columns I would like to use to subset "present" are: > > > * answer (1:4) [answer takes the values 1 to 4] > *p.num (1:18) > * session (1:2) > * count (1:8) > * type (1:3) > > > So there are a total of 3456 possible subsetting combinations. > > > At present, I have been using the following and manually changing the > values in each line and re-running the code. > > input<-subset(input, answer==1) > input.s2g<-subset(input, p.num == 1) > input.s2g<-subset(input.s2g, session == "S2") > input.s2g<-subset(input.s2g, count==8) > input.s2g<-subset(input.s2g, type==1) > > > write.table(s2g, file = "1_1_S2_8_1", sep = "\t", col.names = F, row.names > = F) > > But this takes me hours and is obviously prone to error. There must be an > easier way? > > > Thanks for any 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. > [[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.
