Cartesian product data frame

Question

I have three or more independent variables represented as R vectors, like so:

A <- c(1,2,3)
B <- factor(c(\'x\',\'y\'))
C <- c(0.1,0.5)

Answer 1

Consider using the wonderful data.table library for expressiveness and speed. It handles many plyr use-cases (relational group by), along with transform, subset and relational join using a fairly simple uniform syntax.

library(data.table)
d <- CJ(x=A, y=B, z=C)  # Cross join
d[, w:=f(x,y,z)]  # Mutates the data.table

or in one line

d <- CJ(x=A, y=B, z=C)[, w:=f(x,y,z)]