[R-lang] Re: swapping values without temporary storage

[Martin Corley]

Direct assignment should do it:

x[c(2,3)] <- x[c(3,2)]

--MC
-- 
Martin Corley




On 15 April 2014 18:55:57 "Hofmeister, Philip" <phofme@essex.ac.uk> wrote:

> this is probably more appropriate for a general R listserv, but i'm more 
> likely to get an answer i can decipher here. apologies also for what is 
> likely a simple fix, but i can't seem to find the right term or syntax to 
> get this to work without writing ugly code.
>
> i want to swap values in a vector, e.g.
> x <- c(1, 2, 3)
> [1] 1 2 3
>
> and get back
> 1 3 2
> i can do this by saving the 2nd or 3rd element of the vector elsewhere, 
> replacing one of the vector elements (x[3] <- x[2]), and then restoring the 
> stored value, but that seems wasteful. surely there is a function like 
> swap() or  std::swap(a, b), but i can't seem to find anything. anyone have 
> any ideas?
> ph
>
>
>
>



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