From 0db9c6009de20d172d7218d1e545972133470c9e Mon Sep 17 00:00:00 2001
From: Anthony Scemama <scemama@irsamc.ups-tlse.fr>
Date: Mon, 14 Jun 2021 12:53:38 +0200
Subject: [PATCH] Ideas for improvement

---
 org/qmckl_ao.org | 37 ++++++++++++++++++++++++++++++++++++-
 1 file changed, 36 insertions(+), 1 deletion(-)

diff --git a/org/qmckl_ao.org b/org/qmckl_ao.org
index abdb227..bf7e315 100644
--- a/org/qmckl_ao.org
+++ b/org/qmckl_ao.org
@@ -1331,6 +1331,7 @@ end function test_qmckl_ao_gaussian_vgl
 ** TODO General functions for Slater basis functions
 ** TODO General functions for Radial functions on a grid
 ** Computation of primitives
+
 *** Get
 
     #+begin_src c :comments org :tangle (eval h_func) :noweb yes
@@ -1632,7 +1633,7 @@ print ( "[39][4][1][15] : %e"% lf(a,x,y))
 
 *** Test
 
-     #+begin_src c :tangle (eval c_test)
+     #+begin_src c :tangle (eval c_test) :exports none
 #define walk_num chbrclf_walk_num
 #define elec_num chbrclf_elec_num
 #define prim_num chbrclf_prim_num
@@ -1675,6 +1676,40 @@ assert( fabs(prim_vgl[39][4][1][15] - ( 7.5174404780004771E-003)) < 1.e-14 );
 
 
      #+end_src
+
+*** Ideas for improvement
+
+    #+begin_src c
+// m : walkers
+// j : electrons
+// l : primitives
+
+k=0;
+for (m=0 ; m<walk_num ; ++m) {
+  for (j=0 ; j<elec_num ; ++j) {
+    for (i=0 ; i<nucl_num ; ++i) {
+      
+      r2 = nucl_elec_dist[i][j];
+      
+      if (r2 < nucl_radius2[i]) {
+        
+        for (l=0 ; l<prim_num ; ++l) {
+          tmp[k].i   = i;
+          tmp[k].j   = j;
+          tmp[k].m   = m;
+          tmp[k].ar2 = -expo[l] *r2;
+          ++k;
+        }
+      }
+    }
+  }
+ }
+
+// sort(tmp) in increasing ar2;
+// Identify first ar2 above numerical accuracy threshold
+// Compute vectorized exponentials on significant values
+    #+end_src
+
 * Polynomial part
 ** General functions for Powers of $x-X_i$
    :PROPERTIES: