This can be done very simply because vectors in R can have named elements, and can be indexed by strings.
> stage <- c("1" = 1, "1a" = 1.3, "1b" = 1.5, "1c" = 1.7, + "2" = 2, "2a" = 2.3, "2b" = 2.5, "2c" = 2.7, + "3" = 3, "3a" = 3.3, "3b" = 3.5, "3c" = 3.7) > testdata <- rep(c("1", "1a", "1b", "1c", + "2", "2a", "2b", "2c", + "3", "3a", "3b", "3c"), times=c(1:6,6:1)) > stage[testdata] 1 1a 1a 1b 1b 1b 1c 1c 1c 1c 2 2 2 2 2 2a 2a 2a 2a 2a 1.0 1.3 1.3 1.5 1.5 1.5 1.7 1.7 1.7 1.7 2.0 2.0 2.0 2.0 2.0 2.3 2.3 2.3 2.3 2.3 2a 2b 2b 2b 2b 2b 2b 2c 2c 2c 2c 2c 3 3 3 3 3a 3a 3a 3b 2.3 2.5 2.5 2.5 2.5 2.5 2.5 2.7 2.7 2.7 2.7 2.7 3.0 3.0 3.0 3.0 3.3 3.3 3.3 3.5 3b 3c 3.5 3.7 On Sat, 11 Jul 2020 at 05:51, Jean-Louis Abitbol <abit...@sent.com> wrote: > Dear All > > I have a character vector, representing histology stages, such as for > example: > xc <- c("1", "1a", "1b", "1c", "2", "2a", "2b", "2c") > > and this goes on to 3, 3a etc in various order for each patient. I do have > of course a pre-established classification available which does change > according to the histology criteria under assessment. > > I would want to convert xc, for plotting reasons, to a numeric vector such > as > > xn <- c(1, 1.3, 1.5, 1.7, 2, 2.3, 2.5, 2.7) > > Unfortunately I have no clue on how to do that. > > Thanks for any help and apologies if I am missing the obvious way to do it. > > JL > -- > Verif30042020 > > ______________________________________________ > 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. > [[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.