Source file owl_slicing_basic.ml

# 1 "src/owl/core/owl_slicing_basic.ml"
(*
 * OWL - OCaml Scientific Computing
 * Copyright (c) 2016-2022 Liang Wang <liang@ocaml.xyz>
 *)

open Bigarray
open Owl_types
open Owl_core_types

(* Interface to the native c functions *)

external owl_float32_ndarray_get_slice
  :  ('a, 'b) owl_arr
  -> ('a, 'b) owl_arr
  -> (int64, 'c) owl_arr
  -> unit
  = "stub_float32_ndarray_get_slice"

external owl_float64_ndarray_get_slice
  :  ('a, 'b) owl_arr
  -> ('a, 'b) owl_arr
  -> (int64, 'c) owl_arr
  -> unit
  = "stub_float64_ndarray_get_slice"

external owl_complex32_ndarray_get_slice
  :  ('a, 'b) owl_arr
  -> ('a, 'b) owl_arr
  -> (int64, 'c) owl_arr
  -> unit
  = "stub_complex32_ndarray_get_slice"

external owl_complex64_ndarray_get_slice
  :  ('a, 'b) owl_arr
  -> ('a, 'b) owl_arr
  -> (int64, 'c) owl_arr
  -> unit
  = "stub_complex64_ndarray_get_slice"

let _ndarray_get_slice
    : type a b c.
      (a, b) kind -> (a, b) owl_arr -> (a, b) owl_arr -> (int64, c) owl_arr -> unit
  = function
  | Float32   -> owl_float32_ndarray_get_slice
  | Float64   -> owl_float64_ndarray_get_slice
  | Complex32 -> owl_complex32_ndarray_get_slice
  | Complex64 -> owl_complex64_ndarray_get_slice
  | _         -> failwith "_ndarray_get_slice: unsupported operation"


external owl_float32_ndarray_set_slice
  :  ('a, 'b) owl_arr
  -> ('a, 'b) owl_arr
  -> (int64, 'c) owl_arr
  -> unit
  = "stub_float32_ndarray_set_slice"

external owl_float64_ndarray_set_slice
  :  ('a, 'b) owl_arr
  -> ('a, 'b) owl_arr
  -> (int64, 'c) owl_arr
  -> unit
  = "stub_float64_ndarray_set_slice"

external owl_complex32_ndarray_set_slice
  :  ('a, 'b) owl_arr
  -> ('a, 'b) owl_arr
  -> (int64, 'c) owl_arr
  -> unit
  = "stub_complex32_ndarray_set_slice"

external owl_complex64_ndarray_set_slice
  :  ('a, 'b) owl_arr
  -> ('a, 'b) owl_arr
  -> (int64, 'c) owl_arr
  -> unit
  = "stub_complex64_ndarray_set_slice"

let _ndarray_set_slice
    : type a b c.
      (a, b) kind -> (a, b) owl_arr -> (a, b) owl_arr -> (int64, c) owl_arr -> unit
  = function
  | Float32   -> owl_float32_ndarray_set_slice
  | Float64   -> owl_float64_ndarray_set_slice
  | Complex32 -> owl_complex32_ndarray_set_slice
  | Complex64 -> owl_complex64_ndarray_set_slice
  | _         -> failwith "_ndarray_set_slice: unsupported operation"


(* Core functions for fancy slicing *)

(* encode slice definition consisting only R_ to (start,stop,step) triplets *)
let encode_slice_definition s =
  let t = Genarray.create Int64 C_layout [| 3 * Array.length s |] in
  Array.iteri
    (fun i a ->
      match a with
      | R_ x ->
        let j = 3 * i in
        Genarray.set t [| j |] (Int64.of_int x.(0));
        Genarray.set t [| j + 1 |] (Int64.of_int x.(1));
        Genarray.set t [| j + 2 |] (Int64.of_int x.(2))
      | _    -> failwith "owl_slicing_basic:encode_slice_definition")
    s;
  t


let get kind axis x y =
  let triplets = encode_slice_definition axis in
  _ndarray_get_slice kind x y triplets


let set kind axis x y =
  let triplets = encode_slice_definition axis in
  _ndarray_set_slice kind x y triplets