Still didn't work for me without cbind , although you really don't need it ;)
worked after i set options(stringsAsFactors=F). > options(stringsAsFactors=F) > df<-data.frame(intVec,chaVec) > df intVec chaVec 1 1 a 2 2 b 3 3 c > df$chaVec [1] "a" "b" "c" documentation of data.frame says the option is true by default. Am 10.04.2012 um 17:38 schrieb R. Michael Weylandt: > Don't use cbind() -- it forces everything into a single type, here > string, which in turn becomes factor. > > Simply, > > data.frame(a, b, c) > > Like David mentioned a few days ago, I have no idea who is promoting > this data.frame(cbind(...)) idiom, but it's a terrible idea (albeit > one that seems to be very frequent over the last few weeks) > > Michael > > On Tue, Apr 10, 2012 at 10:33 AM, Anser Chen <anser.c...@gmail.com> wrote: >> Complete newbie to R -- struggling with something which should be pretty >> basic. Trying to create a simple data set (which I gather R refers to as a >> data.frame). So >> >>> a <- c(1,2,3,4,5); >>> b <- c(0.3,0.4,0.5,0,6,0.7); >> >> Stick the two together into a data frame (call test) using cbind >> >>> test <- data.frame(cbind(a,b)) >> >> Seems to do the trick: >> >>> test >> a b >> 1 1 0.3 >> 2 2 0.4 >> 3 3 0.5 >> 4 4 0.6 >> 5 5 0.7 >>> >> >> Confirm that each variable is numeric: >> >>> is.numeric(test$a) >> [1] TRUE >>> is.numeric(test$b) >> [1] TRUE >> >> >> OK, so far so good. But, now I want to merge in a vector of characters: >> >>> c <- c('y1","y2","y3","y4","y5") >> >> Confirm that this is string: >> >>> is.numeric(c); >> [1] FALSE >> >> cbind c into the data frame: >> >>> test <- data.frame(cbind(a,b,c)) >> >> Looks like everything is in place: >> >>> test >> a b c >> 1 1 0.3 y1 >> 2 2 0.4 y2 >> 3 3 0.5 y3 >> 4 4 0.6 y4 >> 5 5 0.7 y5 >> >> Except that it seems as if the moment I cbind in a character vector, it >> changes numeric data to string: >> >>> is.numeric(test$a) >> [1] FALSE >>> is.numeric(test$b) >> [1] FALSE >> >> which would explain why the operations I'm trying to perform on elements of >> a and b columns are failing. If I look at the structure of the data.frame, >> I see that in fact *all* the variables are being entered as "factors". >> >>> str(test) >> 'data.frame': 5 obs. of 3 variables: >> $ a: Factor w/ 5 levels "1","2","3","4",..: 1 2 3 4 5 >> $ b: Factor w/ 5 levels "0.3","0.4","0.5",..: 1 2 3 4 5 >> $ c: Factor w/ 5 levels "y1","y2","y3",..: 1 2 3 4 5 >> >> But, if I try >> >> test <- data.frame(cbind(a,b)) >>> str(test) >> 'data.frame': 5 obs. of 2 variables: >> $ a: num 1 2 3 4 5 >> $ b: num 0.3 0.4 0.5 0.6 0.7 >> >> a and b are coming back as numeric. So, why does cbind'ing a column of >> character variables change everything else? And, more to the point, what do >> I need to do to 'correct' the problem (i.e., stop this from happening). >> >> [[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. > > ______________________________________________ > 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.