On Oct 23, 2013, at 21:50 , William Dunlap wrote: >> s <- sample(1:nrow(data), 40, replace=FALSE) >> y <- data[s,] >> x <- data[-s,] > > If you don't know the size of the sample and it might be 0 then > you have to be a bit more wordy: > x <- data[setdiff(seq_len(nrow(data)), s), ] > or the uglier > x <- if (length(s) > 0) x else x[-s,]
Yes, I took the liberty of assuming that 40 was not 0... (Your "ugly" example seems to have a few problems though. Surely you mean: if (length(s)) data[-s,] else data ). There's also the option of a logical index: N <- nrow(data) n <- 40 ix <- sample(rep(c(TRUE,FALSE), c(n, N-n))) y <- data[ix,] x <- data[!ix,] > > 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 peter dalgaard >> Sent: Wednesday, October 23, 2013 12:37 PM >> To: erinu >> Cc: r-help@r-project.org >> Subject: Re: [R] How to view un-sampled data from a randomly sampled dataset >> >> >> On Oct 23, 2013, at 20:13 , erinu wrote: >> >>> Hi there- >>> >>> I have a 150 row dataset (data). I create "y" a randomly sampled (without >>> replacement) set number of observations (40): >>> >>> y<-data[sample(1:nrow(data),40,replace=FALSE),] >>> >>> I would like to make a new variable "x" that contains the leftover >>> non-sampled 110 observations. I am sure there is a fairly easy way to do >>> this. >>> >>> Any help would be greatly appreciated. >>> >>> THANKS! >>> >> >> Just hold on to the indices: >> >> s <- sample(1:nrow(data), 40, replace=FALSE) >> y <- data[s,] >> x <- data[-s,] >> >> -pd >> >> >>> >>> >>> -- >>> View this message in context: http://r.789695.n4.nabble.com/How-to-view-un- >> sampled-data-from-a-randomly-sampled-dataset-tp4678887.html >>> Sent from the R help mailing list archive at Nabble.com. >>> >>> ______________________________________________ >>> 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. >> >> -- >> Peter Dalgaard, Professor, >> Center for Statistics, Copenhagen Business School >> Solbjerg Plads 3, 2000 Frederiksberg, Denmark >> Phone: (+45)38153501 >> Email: pd....@cbs.dk Priv: pda...@gmail.com >> >> ______________________________________________ >> 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. -- Peter Dalgaard, Professor, Center for Statistics, Copenhagen Business School Solbjerg Plads 3, 2000 Frederiksberg, Denmark Phone: (+45)38153501 Email: pd....@cbs.dk Priv: pda...@gmail.com ______________________________________________ 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.
