reduce_right: Reduce from the right (retired)
In purrr: Functional Programming Tools

reduce_right

R Documentation

Reduce from the right (retired)

Description

These functions were deprecated in purrr 0.3.0. Please use the .dir argument of reduce() instead, or reverse your vectors and use a left reduction.

Usage

reduce_right(.x, .f, ..., .init)

reduce2_right(.x, .y, .f, ..., .init)

accumulate_right(.x, .f, ..., .init)

Arguments

`.x`	A list or atomic vector.
`.f`	For `reduce()`, a 2-argument function. The function will be passed the accumulated value as the first argument and the "next" value as the second argument. For `reduce2()`, a 3-argument function. The function will be passed the accumulated value as the first argument, the next value of `.x` as the second argument, and the next value of `.y` as the third argument. The reduction terminates early if `.f` returns a value wrapped in a `done()`.
`...`	Additional arguments passed on to the mapped function. We now generally recommend against using `...` to pass additional (constant) arguments to `.f`. Instead use a shorthand anonymous function: # Instead of x \|> map(f, 1, 2, collapse = ",") # do: x \|> map(\(x) f(x, 1, 2, collapse = ",")) This makes it easier to understand which arguments belong to which function and will tend to yield better error messages.
`.init`	If supplied, will be used as the first value to start the accumulation, rather than using `.x[[1]]`. This is useful if you want to ensure that `reduce` returns a correct value when `.x` is empty. If missing, and `.x` is empty, will throw an error.
`.y`	For `reduce2()` and `accumulate2()`, an additional argument that is passed to `.f`. If `init` is not set, `.y` should be 1 element shorter than `.x`.