Hi Johannes, Try
df[, !apply(df, 2, function(x) sd(x, na.rm = TRUE) < 1e-10)] HTH, Jorge.- On Thu, May 31, 2012 at 9:27 AM, Johannes Radinger <> wrote: > Hi, > > I have a dataframe and want to remove columns from it > that are populated with a similar value (for the total > column) (the variation of that column is 0). Is there an > easier way than to calculate the statistics and then > remove them by hand? > > A <- runif(100) > B <- rep(1,100) > C <- rep(2.42,100) > D <- runif(100) > df <- data.frame(A,B,C,D) # if want to conditionally remove column B and C > as they show no variations > > /Johannes > -- > > Jetzt informieren: http://mobile.1und1.de/?ac=OM.PW.PW003K20328T7073a > > ______________________________________________ > 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.
