From 5e35df226a640be17bc7726c1e49f3cd226c3b67 Mon Sep 17 00:00:00 2001
From: Anthony Scemama <scemama@irsamc.ups-tlse.fr>
Date: Sun, 27 Feb 2022 11:18:26 +0100
Subject: [PATCH] Fortran interface

---
 org/qmckl_ao.org      | 10 ++++---
 org/qmckl_nucleus.org | 62 ++++++++++++++++++++++++++++++++++++++++---
 2 files changed, 64 insertions(+), 8 deletions(-)

diff --git a/org/qmckl_ao.org b/org/qmckl_ao.org
index 0262c53..c821c67 100644
--- a/org/qmckl_ao.org
+++ b/org/qmckl_ao.org
@@ -1,3 +1,4 @@
+B
 #+TITLE: Atomic Orbitals
 #+SETUPFILE: ../tools/theme.setup
 #+INCLUDE: ../tools/lib.org
@@ -2639,14 +2640,15 @@ qmckl_exit_code qmckl_finalize_basis(qmckl_context context) {
 
 *** HPC-specific data structures
 
-    For faster access, we provide 3D tensors for the shell information
-    as:
+    For faster access, we provide extra arrays for the shell information as:
     - $C_{psa}$ = =coef_per_nucleus (iprim, ishell, inucl)=
     - $\gamma_{pa}$ =expo_per_nucleus (iprim, inucl)=
 
     such that the computation of the radial parts can be vectorized.
+    
     Exponents are sorted in increasing order to exit loops quickly,
-    and only unique exponents are kept.
+    and only unique exponents are kept. This also allows to pack the
+    exponents to enable vectorization of exponentials.
 
     The computation of the radial part is made as
     \[
@@ -2655,7 +2657,7 @@ qmckl_exit_code qmckl_finalize_basis(qmckl_context context) {
     which is a matrix-vector product.
     
     #+NAME:HPC_struct 
-    #+begin_src c :comments org :tangle (eval h_private_type) :exports none
+    #+begin_src c :comments org :exports none
  /* HPC specific data structures */
  qmckl_tensor coef_per_nucleus;
  qmckl_matrix expo_per_nucleus;
diff --git a/org/qmckl_nucleus.org b/org/qmckl_nucleus.org
index 0191afe..319d5d1 100644
--- a/org/qmckl_nucleus.org
+++ b/org/qmckl_nucleus.org
@@ -187,6 +187,19 @@ qmckl_get_nucleus_num (const qmckl_context context, int64_t* const num) {
 }
    #+end_src
 
+    #+begin_src f90 :tangle (eval fh_func) :comments org :exports none
+interface
+  integer(c_int32_t) function qmckl_get_nucleus_num(context, num) &
+    bind(C)
+    use, intrinsic :: iso_c_binding
+    import
+    implicit none
+    integer (c_int64_t) , intent(in)  , value :: context
+    integer (c_int64_t) , intent(out)         :: num
+  end function qmckl_get_nucleus_num
+end interface
+    #+end_src
+
 
    #+begin_src c :comments org :tangle (eval h_func) :exports none
 qmckl_exit_code
@@ -242,6 +255,20 @@ qmckl_get_nucleus_charge (const qmckl_context context,
 
    #+end_src
 
+    #+begin_src f90 :tangle (eval fh_func) :comments org :exports none
+interface
+  integer(c_int32_t) function qmckl_get_nucleus_charge(context, charge, size_max) &
+    bind(C)
+    use, intrinsic :: iso_c_binding
+    import
+    implicit none
+    integer (c_int64_t) , intent(in)  , value :: context
+    real    (c_double)  , intent(out)         :: charge(*)
+    integer (c_int64_t) , intent(in)  , value :: size_max
+  end function qmckl_get_nucleus_charge
+end interface
+    #+end_src
+
 
    #+begin_src c :comments org :tangle (eval h_func) :exports none
 qmckl_exit_code
@@ -277,6 +304,18 @@ qmckl_get_nucleus_rescale_factor (const qmckl_context context,
 }
    #+end_src
 
+    #+begin_src f90 :tangle (eval fh_func) :comments org :exports none
+interface
+  integer(c_int32_t) function qmckl_get_nucleus_rescale_factor(context, kappa) &
+    bind(C)
+    use, intrinsic :: iso_c_binding
+    import
+    implicit none
+    integer (c_int64_t) , intent(in)  , value :: context
+    real    (c_double)  , intent(out)         :: kappa
+  end function qmckl_get_nucleus_rescale_factor
+end interface
+    #+end_src
 
    #+begin_src c :comments org :tangle (eval h_func) :exports none
 qmckl_exit_code
@@ -342,6 +381,21 @@ qmckl_get_nucleus_coord (const qmckl_context context,
 }
    #+end_src
 
+    #+begin_src f90 :tangle (eval fh_func) :comments org :exports none
+interface
+  integer(c_int32_t) function qmckl_get_nucleus_coord(context, transp, coord, size_max) &
+    bind(C)
+    use, intrinsic :: iso_c_binding
+    import
+    implicit none
+    integer (c_int64_t) , intent(in)  , value :: context
+    character(c_char)   , intent(in)  , value :: transp
+    real    (c_double)  , intent(out)         :: coord(*)
+    integer (c_int64_t) , intent(in)  , value :: size_max
+  end function qmckl_get_nucleus_coord
+end interface
+    #+end_src
+
    When all the data relative to nuclei have been set, the following
    function returns ~true~.
 
@@ -424,7 +478,7 @@ interface
     implicit none
     integer (c_int64_t) , intent(in)  , value :: context
     integer (c_int64_t) , intent(in)  , value :: num
-  end function
+  end function qmckl_set_nucleus_num
 end interface
     #+end_src
 
@@ -570,7 +624,7 @@ interface
     character(c_char)   , intent(in)  , value :: transp
     real    (c_double)  , intent(in)          :: coord(*)
     integer (c_int64_t) , intent(in)  , value :: size_max
-  end function
+  end function qmckl_set_nucleus_coord
 end interface
     #+end_src
 
@@ -604,14 +658,14 @@ qmckl_set_nucleus_rescale_factor(qmckl_context context,
 
     #+begin_src f90 :tangle (eval fh_func) :comments org :exports none
 interface
-  integer(c_int32_t) function qmckl_set_rescale_factor(context, kappa) &
+  integer(c_int32_t) function qmckl_set_nucleus_rescale_factor(context, kappa) &
     bind(C)
     use, intrinsic :: iso_c_binding
     import
     implicit none
     integer (c_int64_t) , intent(in)  , value :: context
     real    (c_double)  , intent(in)  , value :: kappa
-  end function
+  end function qmckl_set_nucleus_rescale_factor
 end interface
     #+end_src