is.na<- problem
Hi,
It does seem to be working as advertised, but not particulary
intuitively. From ?is.na
The generic function 'is.na<-' sets elements to 'NA'
In fact:
xx <- c(NA, 1)
is.na(xx) <- 2
xx
[1] NA NA
or is.na(xx) <- 5
[1] NA 1 NA NA NA
Looks like this was introduced in 1.4.0; from NEWS:
o New generic function is.na<-(), from S4. This is by default
equivalent to x[value] <- NA but may differ, e.g. for factors
where "NA" is a level.
Cheers,
Rich
On 10/20/05, Ted Harding <Ted.Harding at nessie.mcc.ac.uk> wrote:
On 19-Oct-05 Gabor Grothendieck wrote:
In the following the first element of xx should have been set to 0 but remains NA. Any comments?
xx <- c(NA,1) is.na(xx) <- 0 xx
[1] NA 1
R.version.string # Windows XP
[1] "R version 2.2.0, 2005-09-20"
I wonder, has it ever worked? I get the same as you on R.version.string #Linux [1] "R version 1.6.2, 2003-01-10" R.version.string #Linux [1] "R version 1.8.0, 2003-10-08" R.version.string #Linux [1] "R version 2.1.0, 2005-04-08" with the exception of R.version.string #Linux [1] "R version 1.2.3, 2001-04-26" which does know about is.na()<- at all. Hmmm Ted. -------------------------------------------------------------------- E-Mail: (Ted Harding) <Ted.Harding at nessie.mcc.ac.uk> Fax-to-email: +44 (0)870 094 0861 Date: 20-Oct-05 Time: 01:11:45 ------------------------------ XFMail ------------------------------
______________________________________________ R-devel at r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
-- Rich FitzJohn rich.fitzjohn <at> gmail.com | http://homepages.paradise.net.nz/richa183 You are in a maze of twisty little functions, all alike