Introducing unique shell pairs

Basis/Contracted_shell.mli

@@ -1,17 +1,5 @@
 type t
-(*
+
-type t = {
-  expo : float array;
-  coef : float array;
-  center : Coordinate.t;
-  totAngMom : Angular_momentum.t;
-  size : int;
-  norm_coef : float array;
-  norm_coef_scale : float array;
-  indice : int;
-  powers : Zkey.t array;
-}
-*)
 
 (** Returns the number of contracted Gaussians *)
 val size : t -> int

Basis/ERI.ml

@@ -72,11 +72,7 @@ let to_file ~filename basis =
 
   (* Pre-compute all shell pairs *)
   let shell_pairs =
-    Array.mapi (fun i shell_a -> Array.map (fun shell_b -> 
+    Shell_pair.shell_pairs basis
-        (*
-        Shell_pair.create_array shell_a shell_b) (Array.sub basis 0 (i+1)) ) basis
-        *)
-        Shell_pair.create_array shell_a shell_b) (basis) ) basis
   in
   Printf.printf "%d shells\n" (Array.length basis);
 
@@ -128,6 +124,11 @@ let to_file ~filename basis =
         let
           shell_p = shell_pairs.(i).(j)
         in
+        (*
+        Printf.printf "%d %d : " i j;
+        Array.iter (fun i -> Printf.printf "%d " (Shell_pair.hash i)) shell_p; 
+        print_newline ();
+        *)
 
         for k=0 to i do
           for l=0 to k do

Basis/Shell_pair.ml

@@ -103,5 +103,26 @@ let create_array ?cutoff p_a p_b =
   |> List.map (function Some x -> x | None -> assert false)
   |> Array.of_list
 
-open Util
+
+let hash a = 
+  Hashtbl.hash (a.expo, a.center_a, a.center_ab, a.coef) 
+
+let cmp a b =
+  hash a - hash b
+
+
+let shell_pairs basis =
+    Array.mapi (fun i shell_a -> Array.map (fun shell_b -> 
+        create_array shell_a shell_b) (Array.sub basis 0 (i+1)) ) basis
+
+
+let unique_shell_pairs basis =
+  let map = 
+    Hashtbl.create 129
+  in
+  Array.iter (fun spa -> 
+    Array.iter (fun value -> 
+      let key = hash value in
+      Hashtbl.add map key value) spa) basis;
+  map