Big thanks for your help and suggestion for email communication.
-s

On Mon, Mar 9, 2009 at 12:18 PM, baptiste auguie <ba...@exeter.ac.uk> wrote:

>
>  On 9 Mar 2009, at 16:04, Sean Zhang wrote:
>
>  Dear Baptiste:
>
> Many thanks for your help!
>
> Using the Reduce way, it works almost perfectly.
> I ran into this problem when thinking of appending vectors.
> Is it possible to not use list() within add()
> so add(vec1,vec2,vec3) below can work?
>
>
> add <- function(...) Reduce("+", list(...))
> add(1, 2, 3)
>
>
>  Also, do you have some  quick hints on using '...'?
>
> Many Thanks in advance.
>
>
>
> I'm not sure of a good reference for this. I'd strongly suggest you read
> the Introduction to R manual ( also check the R project webpage for many
> other resources).
>
> Also, it'd be better if you could Cc R-help next time you ask for further
> information.
>
> Hope this helps,
>
> baptiste
>
>
> vec1<-c(0,1)
> vec2<-c(2,3)
> vec3<-c(4,5)
> add <- function(x) Reduce("append", x)
> add(list(vec1, vec2))
> #add(vec1,vec2) does not work at the moment
>
> -sean
>
>
>
> On Mon, Mar 9, 2009 at 11:50 AM, baptiste auguie <ba...@exeter.ac.uk>wrote:
>
>> Hi,
>>
>>  On 9 Mar 2009, at 15:32, Sean Zhang wrote:
>>
>>  Dear R-helpers:
>> I am an R newbie and have a question related to writing functions that
>> accept unlimited number of input arguments.
>>
>>
>> it's usually through the ... argument, e.g in paste(...).
>>
>>  (I tried to peek into functions such as paste and cbind, but failed, I
>> cannot see their codes..)
>>
>>
>> simply type their name in the R prompt
>>
>> > paste
>>  function (..., sep = " ", collapse = NULL)
>> .Internal(paste(list(...), sep, collapse))
>> <environment: namespace:base>
>>
>> etc...
>>
>> but that's not very useful here.
>>
>>   Can someone kindly show me through a summation example?
>> Say, we have input scalar,  1 2 3 4 5
>> then the ideal function, say sum.test, can do
>> (1+2+3+4+5)==sum.test(1,2,3,4,5)
>>
>>
>> see ?Reduce for one way to do this:
>>
>> add <- function(x) Reduce("+", x)
>>
>> add(list(1, 2, 3))
>>
>>
>> Also sum.test can work as the number of input scalar changes.
>>
>> Many thanks in advance!
>>
>> -sean
>>
>>        [[alternative HTML version deleted]]
>>
>> ______________________________________________
>> R-help@r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide
>> http://www.R-project.org/posting-guide.html<http://www.r-project.org/posting-guide.html>
>> and provide commented, minimal, self-contained, reproducible code.
>>
>>
>>  _____________________________
>>
>> Baptiste AuguiƩ
>>
>> School of Physics
>> University of Exeter
>> Stocker Road,
>> Exeter, Devon,
>> EX4 4QL, UK
>>
>> Phone: +44 1392 264187
>>
>> http://newton.ex.ac.uk/research/emag
>> ______________________________
>>
>>
>
>  _____________________________
>
> Baptiste AuguiƩ
>
> School of Physics
> University of Exeter
> Stocker Road,
> Exeter, Devon,
> EX4 4QL, UK
>
> Phone: +44 1392 264187
>
> http://newton.ex.ac.uk/research/emag
> ______________________________
>
>

        [[alternative HTML version deleted]]

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