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Module Norn.Draws

Equal-weight draws from chains.

Draws of a structure 'u are a value of 'u whose every tensor has two leading axes, [chain; draw], of one length each across tensors. A sampler returns them, and v checks a value for them. Chain diagnostics (Norn.Diag) take draws, so they apply to equal-weight chains only.

#type 'u t = private 'u

The type for draws of 'u. (d :> 'u) reads draws as a value.

#val v : ('u, 'd) Nx.Ptree.t -> 'u -> 'u t

v u x is x as draws.

Raises Invalid_argument if a tensor of x has fewer than two axes, or if two tensors differ in the length of one of their first two axes, naming the path.

#val ptree : ('u, 'd) Nx.Ptree.t -> ('u t, 'd) Nx.Ptree.t

ptree u is the structure of draws of u: u's, with the same paths.

val map : 
  ('a, 'd) Nx.Ptree.t ->
  ('b, 'd) Nx.Ptree.t ->
  ('a -> 'b) ->
  'a t ->
  'b t

map a b f d is f applied to every draw of d, a value of 'a without the two leading axes, the results stacked on them. f runs under Rune.vmap, once for all draws.

val simulate : 
  ('a, 'd) Nx.Ptree.t ->
  ('b, 'd) Nx.Ptree.t ->
  ('d Nx.Rng.key -> 'a -> 'b) ->
  'd Nx.Rng.key ->
  'a t ->
  'b t

simulate a b f k d is map a b of f k_ij over d, where the draw j of chain i has the key Nx.Rng.fold_in k (i * n + j), n being the number of draws per chain.

#val append : ('u, 'd) Nx.Ptree.t -> 'u t -> 'u t -> 'u t

append u d d' is the draws of d followed, in every chain, by those of d'.

Raises Invalid_argument if d and d' differ in their visits (Nx.Ptree.visits) or in their number of chains.

#val thin : ('u, 'd) Nx.Ptree.t -> every:int -> 'u t -> 'u t

thin u ~every d is every every-th draw of each chain of d, from the first.

Raises Invalid_argument if every < 1.