open Printf
open Mpi

(* comm_size, comm_rank *)

let size = comm_size comm_world
let myrank = comm_rank comm_world

let print_array array =
  printf "myrank is %d:\n" myrank;
  for i=1 to (Array.length array) do
    print_int array.(i-1);print_string ";"
  done;
  print_newline ()


let print_farray array =
  printf "myrank is %d:\n" myrank;
  for i=1 to (Array.length array) do
    print_float array.(i-1);print_string ";"
  done;
  print_newline ()


let _ =
  printf "%d: comm_size = %d" myrank size; print_newline()

let _ = 
  print_array (gather 1 0 comm_world)

let _ =
  let a = Array.make 3 0 in
    gather_int 1 a 0 comm_world;
    print_array a

let _ = 
  let a = Array.make 3 0.0 in
    gather_float 3.1 a 0 comm_world;
    print_farray a

let _ = 
  let a = Array.make 6 0 in
    gather_int_array [|1;2|] a 0 comm_world;
    if myrank=0 then print_array a

let _ =
  let a = Array.make 6 0.0 in
    gather_float_array [|1.1;2.1|] a 0 comm_world;
    if myrank=0 then print_farray a