ave2: Apply function over level combinations of factors
In cbaumbach/miscFun: Miscellaneous functions

Description Usage Arguments Value See Also Examples

Group a vector into subsets according to level combinations of one or several factors and apply a function separately to every subset. This function differs from ave in three respects. Firstly, factors have to be supplied in an explicit list. Secondly, the function is a positional parameter. Thirdly and most importantly, there is now a way to supply any number of additional arguments to the function via ... as in the apply-family of functions.

1	ave2(x, factors, f, ...)

`x`	Atomic vector
`factors`	List of factors of the same length as `x`.
`f`	Function
`...`	Further arguments to `f`

A vector of the same length as x. Subsets of the result vector equal the result of applying f to the corresponding subsets of x.

ave

stopifnot(identical(
    ave2(c(1, 2, 3, 4), list(c(1, 1, 2, 2)),
        function(x, sep) {
            paste(x, rev(x), sep = sep)
        }, "-"),
    c("1-2", "2-1", "3-4", "4-3")))