[Rd] is.na<- problem
Martin Maechler
maechler at stat.math.ethz.ch
Thu Oct 20 11:34:18 CEST 2005
>>>>> "Marc" == Marc Schwartz <MSchwartz at mn.rr.com>
>>>>> on Wed, 19 Oct 2005 20:28:05 -0500 writes:
.............
>> > In reviewing the Green Book on the top of page 143, it shows an example
>> > in which the RHS of the assignment are the indices into the LHS object
>> > which are to be set to NA. For example:
>> >
>> > > xx <- c(0:5)
>> >
>> > > xx
>> > [1] 0 1 2 3 4 5
>> >
>> > > is.na(xx) <- c(3, 4)
>> >
>> > > xx
>> > [1] 0 1 NA NA 4 5
>> >
>> >
...........
Marc> In all honesty, while I understood the concept from reading the help
Marc> page, it was not truly clear until I read the Green Book and saw the
Marc> example as to how to actually use the function.
Marc> It would probably be worthwhile to add an example of use to the help
Marc> page.
good idea. I've added a version of yours:
(xx <- c(0:4))
is.na(xx) <- c(2, 4)
xx #> 0 NA 2 NA 4
Martin
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