There is also this syntax for adding variables df[, "var5"] = 1:10
and the syntax sugar for row-oriented storage: df[1:5,] On Wed, Sep 14, 2016 at 11:40 AM, jeremiah rounds <roundsjerem...@gmail.com> wrote: > "If you want to add variable to data.frame you have to use attach, detach. > Right?" > > Not quite. Use it like a list to add a variable to a data.frame > > e.g. > df = list() > df$var1 = 1:10 > df = as.data.frame(df) > df$var2 = 1:10 > df[["var3"]] = 1:10 > df > df = as.list(df) > df$var4 = 1:10 > as.data.frame(df) > > Ironically the primary reason to use a data.frame in my head is to signal > that you are thinking of your data as a row-oriented tabular storage. > "Ironic" because in technical detail that is not a requirement to be a > data.frame, but when I reflect on the typical way a seasoned R programmer > approaches list and data.frames that is basically what they are > communicating. > > I was going to post that a reason to use data.frames is to take advantages > of optimizations and syntax sugar for data.frames, but in reality if code > does not assume a row-oriented data structure in a data.frame there is not > much I can think of that exists in the way of optimization. For example, > we could point to "subset" and say that is a reason to use data.frames and > not list, but that only works if you use data.frame in a conventional way. > > In the end, my advice to you is if it is a table make it a data.frame and > if it is not easily thought of as a table or row-oriented data structure > keep it as a list. > > Thanks, > Jeremiah > > > > > > On Wed, Sep 14, 2016 at 11:15 AM, Alaios via R-help <r-help@r-project.org> > wrote: > >> thanks for all the answers. I think also ggplot2 requires data.frames.If >> you want to add variable to data.frame you have to use attach, detach. >> Right?Any more links that discuss thoe two different approaches?Alex >> >> On Wednesday, September 14, 2016 5:34 PM, Bert Gunter < >> bgunter.4...@gmail.com> wrote: >> >> >> This is partially a matter of subjectve opinion, and so pointless; but >> I would point out that data frames are the canonical structure for a >> great many of R's modeling and graphics functions, e.g. lm, xyplot, >> etc. >> >> As for mutate() etc., that's about UI's and user friendliness, and >> imho my ho is meaningless. >> >> Best, >> Bert >> Bert Gunter >> >> "The trouble with having an open mind is that people keep coming along >> and sticking things into it." >> -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip ) >> >> >> On Wed, Sep 14, 2016 at 6:01 AM, Alaios via R-help <r-help@r-project.org> >> wrote: >> > Hi all,I have seen data.frames and operations from the mutate package >> getting really popular. In the last years I have been using extensively >> lists, is there any reason to not use lists and use other data types for >> data manipulation and storage? >> > Any article that describe their differences? I would like to thank you >> for your replyRegardsAlex >> > [[alternative HTML version deleted]] >> > >> > ______________________________________________ >> > 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/posti >> ng-guide.html >> > and provide commented, minimal, self-contained, reproducible code. >> >> >> >> [[alternative HTML version deleted]] >> >> ______________________________________________ >> 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/posti >> ng-guide.html >> and provide commented, minimal, self-contained, reproducible code. >> > > [[alternative HTML version deleted]] ______________________________________________ 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.
