Hi Naresh If you wanted to automate the function a bit you can use sapply to find numeric columns ind <- sapply(mydf, is.numeric)
and use it in apply construct apply(mydf[,ind], 1, function(row) sum(row)) [1] 2.13002569 0.63305300 1.48420429 0.13523859 1.17515873 -0.98531131 [7] 0.47044467 0.23914494 0.26504430 0.02037657 Cheers Petr > -----Original Message----- > From: R-help <r-help-boun...@r-project.org> On Behalf Of Naresh Gurbuxani > Sent: Tuesday, February 7, 2023 1:52 PM > To: r-help@r-project.org > Subject: [R] preserve class in apply function > > > > Consider a data.frame whose different columns have numeric, character, > > and factor data. In apply function, R seems to pass all elements of a > > row as character. Is it possible to preserve numeric class? > > > >> mydf <- data.frame(x = rnorm(10), y = runif(10)) > >> apply(mydf, 1, function(row) {row["x"] + row["y"]}) > > [1] 0.60150197 -0.74201827 0.80476392 -0.59729280 -0.02980335 > 0.31351909 > > [7] -0.63575990 0.22670658 0.55696314 0.39587314 > >> mydf[, "z"] <- sample(letters[1:3], 10, replace = TRUE) > >> apply(mydf, 1, function(row) {row["x"] + row["y"]}) > > Error in row["x"] + row["y"] (from #1) : non-numeric argument to binary > operator > >> apply(mydf, 1, function(row) {as.numeric(row["x"]) + > as.numeric(row["y"])}) > > [1] 0.60150194 -0.74201826 0.80476394 -0.59729282 -0.02980338 > 0.31351912 > > [7] -0.63575991 0.22670663 0.55696309 0.39587311 > >> apply(mydf[,c("x", "y")], 1, function(row) {row["x"] + row["y"]}) > > [1] 0.60150197 -0.74201827 0.80476392 -0.59729280 -0.02980335 > 0.31351909 > > [7] -0.63575990 0.22670658 0.55696314 0.39587314 > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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 -- To UNSUBSCRIBE and more, see 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.