names(miceTrainSample) [1] "b_double" "KierA2" "KierFlex" "Q_VSA_POS" "pID50" In the above code, how do I delete "pID50" column to store the resulting object without indicating column "5". The code below does the trick, but I wish to delete the column by specifying "-pID50" instead of "5". names(miceTrainSample)[-5] [1] "b_double" "KierA2" "KierFlex" "Q_VSA_POS" -- View this message in context: http://r.789695.n4.nabble.com/Simple-question-regarding-name-of-column-headers-tp2291534p2291534.html Sent from the R help mailing list archive at Nabble.com.
Hi Addi, On Fri, Jul 16, 2010 at 3:22 PM, Addi Wei <addiwei at gmail.com> wrote:> > names(miceTrainSample) > [1] "b_double" ?"KierA2" ? ?"KierFlex" ?"Q_VSA_POS" "pID50" > > In the above code, how do I delete "pID50" column to store the resulting > object without indicating column "5". ?The code below does the trick, but I > wish to delete the column by specifying "-pID50" instead of "5". > > names(miceTrainSample)[-5] > [1] "b_double" ?"KierA2" ? ?"KierFlex" ?"Q_VSA_POS"If I understand you correctly, than this code will not do the trick. All it does is print the column names minus pID50. It does nothing to miceTrainSample. Anyway, I have often wished that something like new.mt.sample <- miceTrainSample[, -"pID50"] would return miceTrainSample without the pID50 column. Here are three alternative ways to do it. # Method 1: Assign NULL to the column new.mt.sample <- miceTrainsSample new.mt.sample$pID50 <- NULL # Method 2: Use which() new.mt.sample <- miceTrainSample[, - which(names(miceTrainSample == "pID50")] # Method 3: use %in% (the one I usually use) new.mt.sample <- miceTrainSample[, ! names(miceTrainSample) %in% "pID50"] Hope it helps, Ista> > -- > View this message in context: http://r.789695.n4.nabble.com/Simple-question-regarding-name-of-column-headers-tp2291534p2291534.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help at r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. >-- Ista Zahn Graduate student University of Rochester Department of Clinical and Social Psychology http://yourpsyche.org
> Anyway, I have often wished that something like > > new.mt.sample <- miceTrainSample[, -"pID50"] > > would return miceTrainSample without the pID50 column. Here are three > alternative ways to do it. > > # Method 1: Assign NULL to the column > new.mt.sample <- miceTrainsSample > new.mt.sample$pID50 <- NULL > > # Method 2: Use which() > new.mt.sample <- miceTrainSample[, - which(names(miceTrainSample == "pID50")] > > # Method 3: use %in% (the one I usually use) > new.mt.sample <- miceTrainSample[, ! names(miceTrainSample) %in% "pID50"]As a variation on Method 1... df <- data.frame(a = 1:10, b = 2:11, c = 3:12) transform(df, a = NULL)
subset(miceTrainSample, select = -plD50) On Fri, Jul 16, 2010 at 11:22 AM, Addi Wei <addiwei at gmail.com> wrote:> > names(miceTrainSample) > [1] "b_double" ?"KierA2" ? ?"KierFlex" ?"Q_VSA_POS" "pID50" > > In the above code, how do I delete "pID50" column to store the resulting > object without indicating column "5". ?The code below does the trick, but I > wish to delete the column by specifying "-pID50" instead of "5". > > names(miceTrainSample)[-5] > [1] "b_double" ?"KierA2" ? ?"KierFlex" ?"Q_VSA_POS" > > -- > View this message in context: http://r.789695.n4.nabble.com/Simple-question-regarding-name-of-column-headers-tp2291534p2291534.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help at 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. >-- Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem that you are trying to solve?