I don't think it has much to do with transform in particular: > BOD <- data.frame(Time = 1:6, demand = runif(6)) > BOD[["X"]] <- BOD[1:2] * seq(6); BOD Time demand X.Time X.demand 1 1 0.8649628 1 0.8649628 2 2 0.5895380 4 1.1790761 3 3 0.6854635 9 2.0563906 4 4 0.4255801 16 1.7023206 5 5 0.5738793 25 2.8693967 6 6 0.9996713 36 5.9980281 > BOD <- data.frame(Time = 1:6, demand = runif(6)) > BOD[["X"]] <- BOD[1] * seq(6); BOD Time demand Time 1 1 0.72990231 1 2 2 0.61721422 4 3 3 0.02389160 9 4 4 0.28341746 16 5 5 0.06116124 25 6 6 0.67966577 36
--Ista On Tue, Jul 24, 2018 at 7:59 AM, Gabor Grothendieck <ggrothendi...@gmail.com> wrote: > The idea is that one wants to write the line of code below > in a general way which works the same > whether you specify ix as one column or multiple columns but the naming > entirely > changes when you do this and BOD[, 1] and transform(BOD, X=..., Y=...) or > other hard coding solutions still require writing multiple cases. > > ix <- 1:2 > transform(BOD, X = BOD[ix] * seq(6)) > > > > On Tue, Jul 24, 2018 at 7:14 AM, Emil Bode <emil.b...@dans.knaw.nl> wrote: >> I think you meant to call BOD[,1] >> From ?transform, the ... arguments are supposed to be vectors, and BOD[1] is >> still a data.frame (with one column). So I don't think it's surprising >> transform gets confused by which name to use (X, or Time?), and kind of >> compromises on the name "Time". It's also in a note in ?transform: "If some >> of the values are not vectors of the appropriate length, you deserve >> whatever you get!" >> And if you want to do it with multiple extra columns (and are not satisfied >> with these labels), I think the proper way to go would be " transform(BOD, >> X=BOD[,1]*seq(6), Y=BOD[,2]*seq(6))" >> >> If you want to trace it back further, it's not in transform but in >> data.frame. Column-names are prepended with a higher-level name if the >> object has more than one column. >> And it uses the tag-name if simply supplied with a vector: >> data.frame(BOD[1:2], X=BOD[1]*seq(6)) takes the name of the only column of >> BOD[1], Time. Only because that column name is already present, it's changed >> to Time.1 >> data.frame(BOD[1:2], X=BOD[,1]*seq(6)) gives third column-name X (as X is >> now a vector) >> data.frame(BOD[1:2], X=BOD[1:2]*seq(6)) or with BOD[,1:2] gives columns >> names X.Time and X.demand, to show these (multiple) columns are coming from X >> >> So I don't think there's much to fix here. I this case having X.Time in all >> cases would have been better, but in general the column-naming of data.frame >> works, changing it would likely cause a lot of problems. >> You can always change the column-names later. >> >> Best regards, >> Emil Bode >> >> Data-analyst >> >> +31 6 43 83 89 33 >> emil.b...@dans.knaw.nl >> >> DANS: Netherlands Institute for Permanent Access to Digital Research >> Resources >> Anna van Saksenlaan 51 | 2593 HW Den Haag | +31 70 349 44 50 | >> i...@dans.knaw.nl <mailto:i...@dans.kn> | dans.knaw.nl >> <applewebdata://71F677F0-6872-45F3-A6C4-4972BF87185B/www.dans.knaw.nl> >> DANS is an institute of the Dutch Academy KNAW <http://knaw.nl/nl> and >> funding organisation NWO <http://www.nwo.nl/>. >> >> On 23/07/2018, 16:52, "R-devel on behalf of Gabor Grothendieck" >> <r-devel-boun...@r-project.org on behalf of ggrothendi...@gmail.com> wrote: >> >> Note the inconsistency in the names in these two examples. X.Time in >> the first case and Time.1 in the second case. >> >> > transform(BOD, X = BOD[1:2] * seq(6)) >> Time demand X.Time X.demand >> 1 1 8.3 1 8.3 >> 2 2 10.3 4 20.6 >> 3 3 19.0 9 57.0 >> 4 4 16.0 16 64.0 >> 5 5 15.6 25 78.0 >> 6 7 19.8 42 118.8 >> >> > transform(BOD, X = BOD[1] * seq(6)) >> Time demand Time.1 >> 1 1 8.3 1 >> 2 2 10.3 4 >> 3 3 19.0 9 >> 4 4 16.0 16 >> 5 5 15.6 25 >> 6 7 19.8 42 >> >> -- >> Statistics & Software Consulting >> GKX Group, GKX Associates Inc. >> tel: 1-877-GKX-GROUP >> email: ggrothendieck at gmail.com >> >> ______________________________________________ >> R-devel@r-project.org mailing list >> https://stat.ethz.ch/mailman/listinfo/r-devel >> >> > > > > -- > Statistics & Software Consulting > GKX Group, GKX Associates Inc. > tel: 1-877-GKX-GROUP > email: ggrothendieck at gmail.com > > ______________________________________________ > R-devel@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-devel ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
