diff --git a/ocaml/Bitlist.ml b/ocaml/Bitlist.ml
index 3e69487e..20c2a17a 100644
--- a/ocaml/Bitlist.ml
+++ b/ocaml/Bitlist.ml
@@ -106,14 +106,14 @@ let of_mo_number_list n_int l =
 
 let to_mo_number_list l =
   let a = Array.of_list l in
-  let mo_tot_num = MO_number.get_mo_tot_num () in
+  let mo_tot_num = MO_number.get_max () in
   let rec do_work accu = function
   | 0 -> accu
   | i ->
       begin
         let new_accu = 
         match a.(i-1) with
-        | Bit.One  -> (MO_number.of_int ~mo_tot_num:mo_tot_num i)::accu 
+        | Bit.One  -> (MO_number.of_int ~max:mo_tot_num i)::accu 
         | Bit.Zero -> accu 
         in
         do_work new_accu (i-1)
diff --git a/ocaml/Input_ao_basis.ml b/ocaml/Input_ao_basis.ml
index a094abd1..c0c20224 100644
--- a/ocaml/Input_ao_basis.ml
+++ b/ocaml/Input_ao_basis.ml
@@ -59,9 +59,10 @@ end = struct
   ;;
 
   let read_ao_nucl () =
+    let nmax = Nucl_number.get_max () in
     (Ezfio.get_ao_basis_ao_nucl () ).Ezfio.data
     |> Ezfio.flattened_ezfio_data
-    |> Array.map ~f:Nucl_number.of_int
+    |> Array.map ~f:(fun x-> Nucl_number.of_int ~max:nmax x)
   ;;
 
   let read_ao_power () =
diff --git a/ocaml/Input_determinants.ml b/ocaml/Input_determinants.ml
index 2f55527e..8b308807 100644
--- a/ocaml/Input_determinants.ml
+++ b/ocaml/Input_determinants.ml
@@ -177,10 +177,10 @@ end = struct
     let n_int = read_n_int () in
     if not (Ezfio.has_determinants_psi_det ()) then
       begin
-        let mo_tot_num = MO_number.get_mo_tot_num () in
+        let mo_tot_num = MO_number.get_max () in
         let rec build_data accu =  function
           | 0 -> accu
-          | n -> build_data ((MO_number.of_int ~mo_tot_num:mo_tot_num n)::accu) (n-1)
+          | n -> build_data ((MO_number.of_int ~max:mo_tot_num n)::accu) (n-1)
         in
         let det_a = build_data [] (Ezfio.get_electrons_elec_alpha_num ())
           |> Bitlist.of_mo_number_list n_int
@@ -248,7 +248,7 @@ end = struct
 
   let to_rst b =
     let mo_tot_num = Ezfio.get_mo_basis_mo_tot_num () in
-    let mo_tot_num = MO_number.of_int mo_tot_num ~mo_tot_num:mo_tot_num in
+    let mo_tot_num = MO_number.of_int mo_tot_num ~max:mo_tot_num in
     let det_text = 
       List.map2_exn ~f:(fun coef det ->
         Printf.sprintf "  %f\n%s\n"
@@ -315,7 +315,7 @@ Determinants ::
 
   let to_string b =
     let mo_tot_num = Ezfio.get_mo_basis_mo_tot_num () in
-    let mo_tot_num = MO_number.of_int mo_tot_num ~mo_tot_num:mo_tot_num in
+    let mo_tot_num = MO_number.of_int mo_tot_num ~max:mo_tot_num in
     Printf.sprintf "
 n_int                  = %s
 bit_kind               = %s
diff --git a/ocaml/Input_nuclei.ml b/ocaml/Input_nuclei.ml
index 969a78b4..1aaa2236 100644
--- a/ocaml/Input_nuclei.ml
+++ b/ocaml/Input_nuclei.ml
@@ -26,8 +26,8 @@ end = struct
   let get_default = Qpackage.get_ezfio_default "nuclei";;
 
   let read_nucl_num () = 
-    Ezfio.get_nuclei_nucl_num ()
-    |> Nucl_number.of_int
+    let nmax = Nucl_number.get_max () in
+    Nucl_number.of_int ~max:nmax nmax
   ;;
 
   let read_nucl_label () =
@@ -75,15 +75,8 @@ end = struct
       else
          extract_begin tail
     in
-    (* Read the xyz data *)
-    let rec read_line = function
-    | [] -> []
-    | line::tail -> 
-      if (String.strip line = "") then []
-      else 
-        (read_line tail)
-    in
     (* Create a list of Atom.t *)
+    let nmax = Nucl_number.get_max () in
     let atom_list = 
       match (extract_begin l) with 
       | _ :: nucl_num :: title :: lines ->
@@ -91,7 +84,7 @@ end = struct
           let nucl_num = nucl_num
           |> String.strip
           |> Int.of_string
-          |> Nucl_number.of_int
+          |> Nucl_number.of_int ~max:nmax
           and lines = Array.of_list lines
           in
           List.init (Nucl_number.to_int nucl_num) ~f:(fun i ->
@@ -101,7 +94,7 @@ end = struct
     in
     (* Create the Nuclei.t data structure *)
     { nucl_num = List.length atom_list
-        |> Nucl_number.of_int;
+        |> Nucl_number.of_int ~max:nmax;
       nucl_label = List.map atom_list ~f:(fun x ->
         x.Atom.element) |> Array.of_list ;
       nucl_charge = List.map atom_list ~f:(fun x ->
diff --git a/ocaml/Molecule.ml b/ocaml/Molecule.ml
index 48c28997..f295420b 100644
--- a/ocaml/Molecule.ml
+++ b/ocaml/Molecule.ml
@@ -25,7 +25,8 @@ let get_multiplicity m =
 ;;
 
 let get_nucl_num m =
-  Nucl_number.of_int (List.length m.nuclei)
+  let nmax = (List.length m.nuclei) in
+  Nucl_number.of_int nmax ~max:nmax
 ;;
 
 let name m = 
diff --git a/ocaml/qp_create_ezfio_from_xyz.ml b/ocaml/qp_create_ezfio_from_xyz.ml
index e4110268..441519ea 100644
--- a/ocaml/qp_create_ezfio_from_xyz.ml
+++ b/ocaml/qp_create_ezfio_from_xyz.ml
@@ -74,9 +74,10 @@ let run ?o b c m xyz_file =
 
   (* Write Basis set *)
   let basis =
+    let nmax = Nucl_number.get_max () in
     let rec do_work (accu:(Atom.t*Nucl_number.t) list) (n:int) = function
     | [] -> accu
-    | e::tail -> let new_accu = (e,(Nucl_number.of_int n))::accu in
+    | e::tail -> let new_accu = (e,(Nucl_number.of_int ~max:nmax n))::accu in
       do_work new_accu (n+1) tail
     in
     do_work [] 1  nuclei
diff --git a/ocaml/qptypes_generator.ml b/ocaml/qptypes_generator.ml
index ffab3bf2..b1c33d85 100644
--- a/ocaml/qptypes_generator.ml
+++ b/ocaml/qptypes_generator.ml
@@ -37,34 +37,6 @@ let input_data = "
   assert (x <> \"\") ;
 
 
-* AO_number : int  
-  assert (x > 0) ; 
-  if (x > 1000) then
-    warning \"More than 1000 AOs\";
-  if (Ezfio.has_ao_basis_ao_num ()) then
-    assert (x <= (Ezfio.get_ao_basis_ao_num ()));
-
-* Nucl_number : int  
-  assert (x > 0) ; 
-  if (x > 1000) then
-    warning \"More than 1000 atoms\";
-  if (Ezfio.has_nuclei_nucl_num ()) then
-    assert (x <= (Ezfio.get_nuclei_nucl_num ()));
-
-* N_int_number : int 
-  assert (x > 0) ; 
-  if (x > 100) then
-    warning \"N_int > 100\";
-  if (Ezfio.has_determinants_n_int ()) then
-    assert (x = (Ezfio.get_determinants_n_int ()));
-
-* Det_number : int 
-  assert (x > 0) ; 
-  if (x > 100000000) then
-    warning \"More than 100 million determinants\";
-  if (Ezfio.has_determinants_n_det ()) then
-    assert (x <= (Ezfio.get_determinants_n_det ()));
-
 * Det_number_max : int 
   assert (x > 0) ; 
   if (x > 100000000) then
@@ -131,38 +103,36 @@ let input_data = "
 "
 ;;
 
+let input_ezfio = "
+* MO_number : int
+  mo_basis_mo_tot_num
+  1 : 10000
+  More than 10000 MOs
+
+* AO_number : int
+  ao_basis_ao_num
+  1 : 10000
+  More than 10000 AOs
+
+* Nucl_number : int
+  nuclei_nucl_num
+  1 : 10000
+  More than 10000 nuclei
+
+* N_int_number : int
+  determinants_n_int
+  1 : 30
+  N_int > 30
+
+* Det_number : int
+  determinants_n_det
+  1 : 100000000
+  More than 100 million determinants
+
+"
+;;
+
 let untouched = "
-module MO_number : sig
-  type t with sexp
-  val to_int : t -> int
-  val get_mo_tot_num : unit -> int 
-  val of_int : ?mo_tot_num:int -> int -> t
-  val to_string : t -> string
-end = struct
-  type t = int with sexp
-  let get_mo_tot_num () =
-    if (Ezfio.has_mo_basis_mo_tot_num ()) then
-      Ezfio.get_mo_basis_mo_tot_num ()
-    else
-      0
-  let to_int x = x
-  let of_int  ?mo_tot_num  x = ( assert (x > 0) ;
-  if (x > 1000) then
-    warning \"More than 1000 MOs\";
-  let mo_tot_num = match mo_tot_num with
-  | Some i -> i
-  | None -> get_mo_tot_num ()
-  in
-  begin
-    match mo_tot_num with
-    | 0 -> ()
-    | i -> assert ( x <= i )
-  end
-  ; x )
-
-  let to_string x = Int.to_string x
-end
-
 "
 
 let template = format_of_string "
@@ -209,9 +179,75 @@ let parse_input input=
   |> print_string
 ;;
 
-let () = 
-  parse_input input_data ;
-  print_endline untouched
+
+let ezfio_template = format_of_string "
+module %s : sig
+  type t with sexp
+  val to_%s : t -> %s
+  val get_max : unit -> %s
+  val of_%s : ?min:%s -> ?max:%s -> %s -> t
+  val to_string : t -> string
+end = struct
+  type t = %s with sexp
+  let to_string x = %s.to_string x
+  let get_max () =
+    if (Ezfio.has_%s ()) then
+      Ezfio.get_%s ()
+    else
+      %s
+  let get_min () =
+      %s
+  let to_%s x = x
+  let of_%s ?(min=get_min ()) ?(max=get_max ()) x = 
+    begin
+      assert (x >= min) ;
+      if (x > %s) then
+        warning \"%s\";
+      begin
+        match max with
+        | %s -> ()
+        | i  -> assert ( x <= i )
+      end ;
+      x
+    end
+end
+"
 ;;
 
+let parse_input_ezfio input=
+  let parse s = 
+    match (
+      String.split s ~on:'\n'
+      |> List.filter ~f:(fun x -> (String.strip x) <> "")
+    ) with
+    | [] -> ""
+    | a :: b :: c :: d :: [] ->
+      begin
+        let (name,typ) = String.lsplit2_exn ~on:':' a
+        and ezfio_func = b
+        and (min, max) = String.lsplit2_exn ~on:':' c
+        and msg = d
+        in 
+        let name :: typ :: ezfio_func :: min :: max :: msg :: [] = 
+            name :: typ :: ezfio_func :: min :: max :: msg :: []
+           |> List.map ~f:String.strip 
+        in
+        Printf.sprintf ezfio_template 
+          name typ typ typ typ typ typ typ typ (String.capitalize typ)
+          ezfio_func ezfio_func max min typ typ max msg min
+      end
+    | _ -> failwith "Error in input_ezfio"
+  in
+     String.split ~on:'*' input
+  |> List.map ~f:parse
+  |> String.concat 
+  |> print_string
+;;
+
+let () = 
+  parse_input input_data ;
+  parse_input_ezfio input_ezfio;
+  print_endline untouched;
+
+