Here is a way of using parse and eval that was previously mentioned. It works with constants, variable names or expressions:
> myFunc <- function(arg1, arg2) arg1+arg2 > > x <- 20 > y <- 10 > myFunc(x,y) [1] 30 > > tempstr <- 'x,y' > # split the string > args <- strsplit(tempstr, ',') > # parse and eval the characters > myFunc(eval(parse(text=args[[1]][1])), eval(parse(text=args[[1]][2]))) [1] 30 > > tempstr <- '10,20' > # split the string > args <- strsplit(tempstr, ',') > # parse and eval the characters > myFunc(eval(parse(text=args[[1]][1])), eval(parse(text=args[[1]][2]))) [1] 30 > > tempstr <- '2 * 5, 40 / 2' #works with expressions > # split the string > args <- strsplit(tempstr, ',') > # parse and eval the characters > myFunc(eval(parse(text=args[[1]][1])), eval(parse(text=args[[1]][2]))) [1] 30 > > On 10/29/07, Gang Chen <[EMAIL PROTECTED]> wrote: > Thanks for the help. > > One case is like this: With function MyFunc(Argument1, > Argument2, ...) I have the first two arguments defined as one > variable "tempstr", a string of characters, like > > tempstr <- "Argument1, Argument2" > > The question is how I can feed tempstr into MyFunc to make it > executable? > > Gang > > On Oct 29, 2007, at 5:42 PM, jim holtman wrote: > > > Can you provide an example of your input and what you expect the > > output to be. You can always use 'as.numeric'. > > > > On 10/29/07, Gang Chen <[EMAIL PROTECTED]> wrote: > >> This must be very simple, but I'm stuck. I have a command line in R > >> defined as a variable of a string of characters. How can I convert > >> the variable so that I can execute it in R? > >> > >> Really appreciate any help, > >> Gang > -- Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem you are trying to solve? ______________________________________________ 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 and provide commented, minimal, self-contained, reproducible code.
