R help - Nov 2010 - using the "apply" method for functions with multiple inputs

hello r users,

i'm trying to use the apply method on a function with several inputs, but
cannot figure out how to send multiple arguments to the function (not
multiple runs of the same function, but one run of the function including
two variables - each used within the function).

a <- c(1:10,999,999,999)
b <- c(11:20,999,999,999)

tfun <- function(x,y){
  if( (x = 1 & y !=999) || (x > 1 & x < 999 & y == 999) )
    x1 <- 1
  else
    x1 <-0
}

#this doesn't work - gives an error " 'y' is missing
tfilt <- sapply(data.frame(a,b), tfun)

thanks,
joe

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On Nov 22, 2010, at 8:38 PM, joeponzio wrote:
>
> hello r users,
>
> i'm trying to use the apply method on a function with several  
> inputs, but
> cannot figure out how to send multiple arguments to the function (not
> multiple runs of the same function, but one run of the function  
> including
> two variables - each used within the function).
>
> a <- c(1:10,999,999,999)
> b <- c(11:20,999,999,999)
>
> tfun <- function(x,y){
>  if( (x = 1 & y !=999) || (x > 1 & x < 999 & y == 999) )
There is a problem with that first logical test, assigns 1 to x rather  
than testing.
>    x1 <- 1
>  else
>    x1 <-0
> }
>
 > mapply("tfun", a, b)
  [1] 1 1 1 1 1 1 1 1 1 1 0 0 0

(but see above if that were not what you expected.)
> #this doesn't work - gives an error " 'y' is missing
> tfilt <- sapply(data.frame(a,b), tfun)
>
> thanks,
> joe
>
> -- 
> View this message in context:
http://r.789695.n4.nabble.com/using-the-apply-method-for-functions-with-multiple-inputs-tp3054719p3054719.html
> Sent from the R help mailing list archive at Nabble.com.
>
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