Evaluate a distance spec at a single target

Evaluate a distance spec at a single target

Usage

distance_eval(spec, X, x0, ctx = NULL)

Arguments

spec

Distance spec (see is_distance()).

X

Numeric matrix \(n x p\).

x0

Numeric vector length \(p\).

ctx

Optional context; if NULL and spec$setup exists, it will be called as spec$setup(X) to create a context.

Value

Numeric vector length n.

Examples

x_mat <- matrix(rnorm(12), 4, 3)
x0_vec <- c(0, 0, 0)
distance_eval(distance_l2(), x_mat, x0_vec)
#> [1] 1.664026 1.179849 0.938389 2.523089