Is this a distance spec?

A distance spec is a list with eval(X, x0, ctx) and/or eval_batch(X, X0, ctx). It may optionally define setup(X) to precompute a context (e.g., scaling).

Usage

is_distance(x)

Arguments

x

Any R object.

Value

Logical.

Examples

is_distance(distance_l2())
#> [1] TRUE
is_distance(list(eval = function(X, x0, ctx) rep(0, nrow(X))))
#> [1] TRUE