Use is.na().
Since NA denotes unknown, the result is always unknown.
On Sat, 29 Jun 2002, Remigijus Lapinskas wrote:
> Hello R-help,
>
> My vector aa has some NA's:
>
> > aa_c(NA,1)
Oh, please don't post ugly code like that. If you must use `_' leave
spaces around it (and be aware that it will be deprecated in 1.6.0).
> > aa=="NA"
> [1] NA FALSE
> > aa==NA
> [1] NA NA
>
> How can I detect NA's?
> In other words, I would like my answer to be TRUE FALSE.
>
> Best regards,
> Remigijus mailto:remigijus.lapinskas at maf.vu.lt
>
>
>
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--
Brian D. Ripley, ripley at stats.ox.ac.uk
Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/
University of Oxford, Tel: +44 1865 272861 (self)
1 South Parks Road, +44 1865 272860 (secr)
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