Execute a function
Inline. -- Bert
On Fri, Jul 20, 2012 at 6:59 AM, Peter Ehlers <ehlers at ucalgary.ca> wrote:
On 2012-07-20 04:05, carla moreira wrote:
Hi,
I would like to evaluate a function, with 3 arguments, for instance,
myfunc<-function(a,b,c) { sqrt(a)-exp(b)+4*c
}
How to execute myfunc(x,y,z), for all x, all y and all z, where x,y,z are
vectors?
Is this what you have in mind:
myfunc <- function(a, b, c){ sqrt(a)-exp(b)+4*c }
myfunc2 <- function(x){
a <- x[1]
b <- x[2]
c <- x[3]
myfunc(a, b, c)
}
x <- c(1, 4, 9)
y <- 1:2
z <- c(10, -10, 2, 20)
d <- expand.grid(x, y, z)
Peter, what's wrong with with(d,myfunc(x,y,z)) ?? I realize this depends on the function be vectorizable, but isn't that the point? It could be orders of magnitude faster than looping via apply. -- Bert
d$value <- apply(d, 1, myfunc2) ? Peter Ehlers
Thank you very much in advance -- View this message in context: http://r.789695.n4.nabble.com/Execute-a-function-tp4637182.html Sent from the R help mailing list archive at Nabble.com.
______________________________________________ R-help at 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.
______________________________________________ R-help at 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.
Bert Gunter Genentech Nonclinical Biostatistics Internal Contact Info: Phone: 467-7374 Website: http://pharmadevelopment.roche.com/index/pdb/pdb-functional-groups/pdb-biostatistics/pdb-ncb-home.htm