Thank you, but I already know that. I am not surprised by this behavior,
but by an inconsistency between that behavior and the documentation that
says "For factors, this uses the levels (labels).", which it does not.
Best,
Philippe
On 15/08/10 16:09, R Help wrote:
The problem is that, underneath the factors are actually numbers (1
and 2), where as, if you extract the levels and then get the logical,
it converts them to strings and then to logicals. I run into this
problem ALL THE TIME with numerics in a dataset. Consider the
following:
factor(c(3,6,5,2,7,8,4))
[1] 3 6 5 2 7 8 4
Levels: 2 3 4 5 6 7 8
as.numeric(factor(c(3,6,5,2,7,8,4)))
[1] 2 5 4 1 6 7 3
as.numeric(as.character(factor(c(3,6,5,2,7,8,4))))
[1] 2 3 4 5 6 7 8
as.logical converts all non-zeros to TRUE, and 0 to false:
as.logical(0:10)
[1] FALSE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE TRUE
Hope that helps,
Sam
On Sun, Aug 15, 2010 at 5:32 AM, Philippe Grosjean
<phgrosj...@sciviews.org> wrote:
Hello,
According to ?as.logical:
"as.logical attempts to coerce its argument to be of logical type. For
factors, this uses the levels (labels)."
However,
as.logical(factor(c("FALSE", "TRUE")))
[1] TRUE TRUE
Shouldn't it be the same as:
as.logical(levels(factor(c("FALSE", "TRUE"))))
[1] FALSE TRUE
according to the documentation? Did I miss something here?
sessionInfo()
R version 2.11.1 RC (2010-05-29 r52140)
x86_64-apple-darwin9.8.0
locale:
[1] C/UTF-8/C/C/C/C
attached base packages:
[1] stats graphics grDevices utils datasets methods base
Thanks,
Philippe
--
..............................................<°}))><........
) ) ) ) )
( ( ( ( ( Prof. Philippe Grosjean
) ) ) ) )
( ( ( ( ( Numerical Ecology of Aquatic Systems
) ) ) ) ) Mons University, Belgium
( ( ( ( (
..............................................................
______________________________________________
R-help@r-project.org mailing list
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.
______________________________________________
R-help@r-project.org mailing list
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.
