[R] function corresponding to map of perl

[Fernando Saldanha]

I defined map as follows:

map <- function(x, y, fun) {
	mymat <- matrix( c(x,y), c(length(x), 2) )
	tmat <- t(mymat)
	oldmat <- tmat
	result <- apply(tmat, 2, function(x) {fun(x[1], x[2])})
}

It seems to work (see below). Of course you can turn it into a one-liner.

> a<-c(1,2,3)
> b<-c(4,5,6)
> mysum <- function(x, y) {x + y}
> map <- function(x, y, fun) {
+ mymat <- matrix( c(x,y), c(length(x), 2) )
+ tmat <- t(mymat)
+ oldmat <- tmat
+ result <- apply(tmat, 2, function(x) {fun(x[1], x[2])})
+ }
> (test <- map(a, b, mysum))
[1] 5 7 9