wf: Get the index of the first/last TRUE

In checkmate: Fast and Versatile Argument Checks

Get the index of the first/last TRUE

Description

A quick C implementation for “which.first” (head(which(x), 1)) and “which.last” (tail(which(x), 1)).

Usage

wf(x, use.names = TRUE)

wl(x, use.names = TRUE)

Arguments

x	[logical] Logical vector.
use.names	[logical(1)] If TRUE and x is named, the result is also named.

Value

[integer(1) | integer(0)]. Returns the index of the first/last TRUE value in x or an empty integer vector if none is found. NAs are ignored.

Examples

wf(c(FALSE, TRUE))
wl(c(FALSE, FALSE))
wf(NA)

checkmate documentation built on Sept. 11, 2024, 8:40 p.m.