let mu = 5.0

let hybrid vdp_c() = (x, y) where
  rec der x = y init 1.0
  and der y = (mu *. (1.0 -. (x *. x)) *. y) -. x init 1.0

let node forward(h)(x0, x') = x where
  rec x = x0 fby (x +. h *. x')

let node backward(h)(x0, x') = x where
  rec x = x0 -> pre x +. h *. x'

let node vdp_d(h)() = (x, y) where
  rec x = backward(h)(1.0, y)
  and y = forward(h)(1.0, (mu *. (1.0 -. (x *. x)) *. y) -. x)

let stop_time = 50.0

let node print (t, (x, y)) =
  print_endline (String.concat ",\t" (List.map string_of_float [t;x;y]))

let node main_d() =
  let rec t = 0.0 -> pre t +. 0.001 in
  print(t, vdp_d(0.001)())

let node main_dc() =
  let rec (t0, (x0, y0)) = ((0.0 -> pre t0 +. 0.1), vdp_d(0.1)()) in
  let rec (t1, (x1, y1)) = ((0.0 -> pre t1 +. 0.2), vdp_d(0.2)()) in
  let rec (t2, (x2, y2)) = ((0.0 -> pre t2 +. 0.3), vdp_d(0.3)()) in
  let rec (t3, (x3, y3)) = ((0.0 -> pre t3 +. 0.4), vdp_d(0.4)()) in
  let rec (t4, (x4, y4)) = ((0.0 -> pre t4 +. 0.5), vdp_d(0.5)()) in
  let rec (t5, (x5, y5)) = ((0.0 -> pre t5 +. 0.6), vdp_d(0.6)()) in
  let rec (t6, (x6, y6)) = ((0.0 -> pre t6 +. 0.7), vdp_d(0.7)()) in
  let rec (t7, (x7, y7)) = ((0.0 -> pre t7 +. 0.8), vdp_d(0.8)()) in
  let rec (t8, (x8, y8)) = ((0.0 -> pre t8 +. 0.9), vdp_d(0.9)()) in
  let rec (t9, (x9, y9)) = ((0.0 -> pre t9 +. 1.0), vdp_d(1.0)()) in
  print_endline (String.concat "\t" [string_of_float t0; "x0"; string_of_float x0; "y0"; string_of_float y0]);
  print_endline (String.concat "\t" [string_of_float t1; "x1"; string_of_float x1; "y1"; string_of_float y1]);
  print_endline (String.concat "\t" [string_of_float t2; "x2"; string_of_float x2; "y2"; string_of_float y2]);
  print_endline (String.concat "\t" [string_of_float t3; "x3"; string_of_float x3; "y3"; string_of_float y3]);
  print_endline (String.concat "\t" [string_of_float t4; "x4"; string_of_float x4; "y4"; string_of_float y4]);
  print_endline (String.concat "\t" [string_of_float t5; "x5"; string_of_float x5; "y5"; string_of_float y5]);
  print_endline (String.concat "\t" [string_of_float t6; "x6"; string_of_float x6; "y6"; string_of_float y6]);
  print_endline (String.concat "\t" [string_of_float t7; "x7"; string_of_float x7; "y7"; string_of_float y7]);
  print_endline (String.concat "\t" [string_of_float t8; "x8"; string_of_float x8; "y8"; string_of_float y8]);
  print_endline (String.concat "\t" [string_of_float t9; "x9"; string_of_float x9; "y9"; string_of_float y9])

let input _ = ()
let vdp_s = Solve.solve_sundials vdp_c

let node main_c() =
  let o = run vdp_s (Some (Solve.make(stop_time, input)) fby None) in
  Solve.period'_t 1.0 print o