apple-0.3.0.0: math/stats/whiten.apple
λm.
{
sd ← λxs. {n ⟜ ℝ(:xs); μ ⟜((+)/xs)%n; √(((+)/([{d⟜x-μ; d^2}]'xs))%n)};
⍉((λxs. {σ ⟜ sd xs; (%σ)'xs})`{1} (m::M float))
}
λm.
{
sd ← λxs. {n ⟜ ℝ(:xs); μ ⟜((+)/xs)%n; √(((+)/([{d⟜x-μ; d^2}]'xs))%n)};
⍉((λxs. {σ ⟜ sd xs; (%σ)'xs})`{1} (m::M float))
}