[R] subset(..., drop=TRUE) doesn't seem to work.

[Paul Lemmens]

Hoi Peter,

--On woensdag 16 juni 2004 17:35 +0200 Peter Dalgaard 
<p.dalgaard at biostat.ku.dk> wrote:
> Anyways, the way out is
>
>  d2 <- subset(dd,c==1)
>  ifac <- sapply(dd,is.factor)
>  d2[ifac] <- lapply(d2[ifac],factor)
>
> or
>
>  d2 <- subset(dd,c==1)
>  d2[] <- lapply(d2, function(x) if (is.factor(x)) factor(x) else x)
>
My toolbox.r now contains:

my.subset <- function(x, drop.unused.levels=FALSE, ...) {
  subsetted <- subset(x, ...)

  if (drop.unused.levels) {
    subsetted[] <- lapply(subsetted,
                      function(x) if (is.factor(x)) factor(x) else x)
  }

  subsetted
}


Thnx for all the help!



-- 
Paul Lemmens
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