R help - Aug 2009 - How to generate an error message when 'match' does not find any matches?

Hi,
> match(4, c(1,2,3))
[1] NA

The above code run smoothly. It would not stop when 4 does not mach in
c(1,2,3). I am wondering if there is a way to stop the code and pop up
an error message immediately. This capability to stop will make
debugging easier.

Regards,
Peng

Try this:

m <- match(4, c(1,2,3))
ifelse(is.na(m), stop("Not Found"), m)

Or:

stopifnot(!is.na(m))

On Sat, Aug 22, 2009 at 9:36 PM, Peng Yu <pengyu.ut@gmail.com> wrote:
> Hi,
>
> > match(4, c(1,2,3))
> [1] NA
>
> The above code run smoothly. It would not stop when 4 does not mach in
> c(1,2,3). I am wondering if there is a way to stop the code and pop up
> an error message immediately. This capability to stop will make
> debugging easier.
>
> Regards,
> Peng
>
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> PLEASE do read the posting guide
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>


-- 
Henrique Dallazuanna
Curitiba-Paraná-Brasil
25° 25' 40" S 49° 16' 22" O

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