Ferdinand Alimadhi wrote: > tmp$comp <- [EMAIL PROTECTED] ?! I "lose" class here and that is not what I want. Perhaps I should stick with list instead of data.frame.
> Gregor Gorjanc wrote: > >> Hello! >> >> I am developing a composition class, which represents a composition of >> mixture of levels, say soil has three components and each component >> accounts for 1/3 of the unit. I have tried with S4 class system and I >> would appreciate any help here. I was hoping that I would be able to >> include instance of my class into a data.frame. However, I encounter >> problems. >> >> Simple definition of class could be >> >> setClass(Class="composition", >> representation=representation(ratios="matrix")) >> >> n <- 2 >> k <- 3 >> >> x <- new(Class="composition", ratios=matrix(data=rep(x=1/3, times=n*k), >> nrow=n, ncol=k)) >> >> x >> An object of class "composition" >> Slot "ratios": >> [,1] [,2] [,3] >> [1,] 0.3333333 0.3333333 0.3333333 >> [2,] 0.3333333 0.3333333 0.3333333 >> >> tmp <- data.frame(id=1:2) >> tmp$comp <- x >> Error: object is not subsettable >> >> As I understand this, my problem is that x is of length 1 as the >> following works >> >> tmp$comp <- c(x, x) >> >> although I am not able to print tmp now >> >> tmp >> Error in unlist(x, recursive, use.names) : >> argument not a list >> >> but this is expected as I (probably) need show/print method for this. >> How can I put my class into data.frame or how can I make my class behave >> as a vector? >> >> Thanks! -- Lep pozdrav / With regards, Gregor Gorjanc ---------------------------------------------------------------------- University of Ljubljana PhD student Biotechnical Faculty Zootechnical Department URI: http://www.bfro.uni-lj.si/MR/ggorjan Groblje 3 mail: gregor.gorjanc <at> bfro.uni-lj.si SI-1230 Domzale tel: +386 (0)1 72 17 861 Slovenia, Europe fax: +386 (0)1 72 17 888 ---------------------------------------------------------------------- "One must learn by doing the thing; for though you think you know it, you have no certainty until you try." Sophocles ~ 450 B.C. ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel