On 7/19/05, Dirk Enzmann <[EMAIL PROTECTED]> wrote: > Although I tried to find an answer in the manuals and archives, I cannot > solve this (please excuse that my English and/or R programming skills > are not good enough to state my problem more clearly): > > I want to write a function with an indeterminate (not pre-defined) > number of arguments and think that I should use the "..." construct and > the match.call() function. The goal is to write a function that (among > other things) uses cbind() to combine a not pre-defined number of > vectors specified in the function call. For example, if my vectors are > x1, x2, x3, ... xn, within the function I want to use cbind(x1, x2) or > cbind(x1, x3, x5) or ... depending on the vector names I use in the > funcion call. Additionally, the function has other arguments. > > In the archives I found the following thread (followed by Marc Schwartz) > > http://finzi.psych.upenn.edu/R/Rhelp02a/archive/15186.html > [R] returning argument names from Peter Dalgaard BSA on 2003-04-10 (stdin) > > that seems to contain the solution to my problem, but I am stuck because > sapply(match.call()[-1], deparse) gives me a vector of strings and I > don't know how to use the names in this vector in the cbind() function. > > Up to now my (clearly deficit) function looks like: > > test <- function(..., mvalid=1) > { > args = sapply(match.call()[-1], deparse) > # and here, I don't know how the vector names in args > # can be used in the cbind() function to follow: > # > # temp <- cbind( ??? > if (mvalid > 1) > { > # here it goes on > } > } > > Ultimately, I want that the function can be called like > test(x1,x2,mvalid=1) > or > test(x1,x3,x5,mavlid=2) > and that within the function > cbind(x1,x2) > or cbind(x1,x3,x5) > will be used. >
If you just need to pass them to cbind then just use cbind(...), e.g. test <- function(..., m) if (m > 1) cbind(...) else m otherwise, use list(...) as shown by a previous answer or here test2 <- function(..., m) if (m > 1) length(list(...)) else m ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
