Hi Eduardo, To shamelessly borrow from the Princess Bride:
“Why do you use a data frame? Are you touched in the head? "Oh no. It's just they're terribly practical. I think everyone will be using them in the future.” Using data frames is what Hadley intended, and once you get used to it, it is not nearly as restrictive as you might think. This does what you want, I believe. Rather than creating extraneous variables, I simply perform various transformations on 'x' within the plotting code. require(ggplot2) dfm <- data.frame(x = 1:10) qplot(x = x, y = sqrt(x), data = dfm, geom = "line", colour = I("darkgreen")) + geom_line(aes(x = x, y = log(x)), colour = "red") Cheers, Josh On Tue, Jan 4, 2011 at 6:56 PM, Eduardo de Oliveira Horta <eduardo.oliveiraho...@gmail.com> wrote: > Hello, > > this is probably a recurrent question, but I couldn't find any answers that > didn't involve the expression "data frame"... so perhaps I'm looking for > something new here. > > I wanted to find a code equivalent to > >> x=sqrt(1:10) >> y=log(1:10) >> plot(1:10, x, type="lines", col="darkgreen") >> lines(1:10, y, col="red") > > to use with ggplot2. I've tried > >> x=sqrt(1:10) >> y=log(1:10) >> qplot(1:10, x, geom="line", colour=I("darkgreen")) ##### note you would also need a + after the qplot() code to add geom_line() ##### >> geom_line(1:10, y, colour="red") > Error: ggplot2 doesn't know how to deal with data of class numeric > > but it seems that the "data frame restriction" is really very restrictive > here. Any solutions that don't imply using as.data.frame to my data? > > Thanks in advance, and best regards! > > Eduardo Horta > > [[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. > -- Joshua Wiley Ph.D. Student, Health Psychology University of California, Los Angeles http://www.joshuawiley.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.