From e425b24303923ff640e654c059a5c5e24e75bf2d Mon Sep 17 00:00:00 2001
From: v1j4y <vijay.gopal.c@gmail.com>
Date: Mon, 4 Oct 2021 15:42:22 +0200
Subject: [PATCH] Added context. #41

---
 org/qmckl_mo.org                 |   7 +--
 org/qmckl_slater_determinant.org | 101 +++++++++++++++++++++++++++++++
 2 files changed, 102 insertions(+), 6 deletions(-)

diff --git a/org/qmckl_mo.org b/org/qmckl_mo.org
index a884ed6..f521b4d 100644
--- a/org/qmckl_mo.org
+++ b/org/qmckl_mo.org
@@ -80,12 +80,7 @@ int main() {
 
   |---------------------+--------------------+--------------------------------------------------------------|
   | ~type~              |                    | Gaussian (~'G'~) or Slater (~'S'~)                           |
-  | ~nucleus_index~     | ~[nucl_num]~       | Index of the first shell of each nucleus                     |
-  | ~nucleus_shell_num~ | ~[nucl_num]~       | Number of shells per nucleus                                 |
-  | ~ao_num~            |                    | Number of AOs                                                |
-  | ~ao_cartesian~      |                    | If true, use polynomials. Otherwise, use spherical harmonics |
-  | ~ao_factor~         | ~[ao_num]~         | Normalization factor of the AO                               |
-  | ~ao_shell~          | ~[ao_num]~         | For each AO, specify to which shell it belongs               |
+  | ~mo_num~            |                    | Number of MOs                                                |
   | ~coefficient~       | ~[mo_num, ao_num]~ | Orbital coefficients                                         |
 
   Computed data:
diff --git a/org/qmckl_slater_determinant.org b/org/qmckl_slater_determinant.org
index 293f088..30aa7d7 100644
--- a/org/qmckl_slater_determinant.org
+++ b/org/qmckl_slater_determinant.org
@@ -2,5 +2,106 @@
 #+SETUPFILE: ../tools/theme.setup
 #+INCLUDE: ../tools/lib.org
 
+The slater deteminant is required for the calculation of the
+wavefunction, gradient, and derivatives. These quantities will be used
+to calculate the local Energy (\[E_L\]).
+
+ψ(x) = det|ϕ₁(x₁)...ϕᵢ(yᵢ)...ϕₙ(xₙ)|
+
+Concerning the gradient and laplacian, in fact what is actually
+calculated is the ratio of the gradient/laplacian and the determinant
+of the slater matrix:
+
+∇ψ(x)/ψ(x)
+
+and
+
+∇²ψ(x)/ψ(x)
+
+This avoids the unnecessary multiplication and division of by the
+determinant ψ(x).
 
 
+* Headers                                                          :noexport:
+  #+begin_src elisp :noexport :results none
+(org-babel-lob-ingest "../tools/lib.org")
+  #+end_src
+
+
+  #+begin_src c :tangle (eval h_private_type)
+#ifndef QMCKL_MO_HPT
+#define QMCKL_MO_HPT
+
+#include <stdbool.h>
+  #+end_src
+
+  #+begin_src c :tangle (eval c_test) :noweb yes
+#include "qmckl.h"
+#include "assert.h"
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <stdio.h>
+#include <math.h>
+#include "chbrclf.h"
+#include "qmckl_ao_private_func.h"
+#include "qmckl_mo_private_func.h"
+#include "qmckl_slater_determinant_private_func.h"
+
+int main() {
+    qmckl_context context;
+    context = qmckl_context_create();
+
+    qmckl_exit_code rc;
+  #+end_src
+
+  #+begin_src c :tangle (eval c)
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#ifdef HAVE_STDINT_H
+#include <stdint.h>
+#elif HAVE_INTTYPES_H
+#include <inttypes.h>
+#endif
+
+#include <stdlib.h>
+#include <string.h>
+#include <stdbool.h>
+#include <assert.h>
+
+#include "qmckl.h"
+#include "qmckl_context_private_type.h"
+#include "qmckl_memory_private_type.h"
+#include "qmckl_memory_private_func.h"
+#include "qmckl_ao_private_type.h"
+#include "qmckl_ao_private_func.h"
+#include "qmckl_mo_private_type.h"
+#include "qmckl_mo_private_func.h"
+#include "qmckl_slater_determinant_private_type.h"
+#include "qmckl_slater_determinant_private_func.h"
+  #+end_src
+
+* Context
+
+  The following arrays are stored in the context:
+
+  |-----------------+-------------------------------+------------------------------------|
+  | ~type~          | ~char~                        | α (~'A'~) or β (~'B'~) determinant |
+  | ~walk_num~      | ~uint64_t~                    | Number of walkers                  |
+  | ~det_num~       | ~uint64_t~                    | Number of determinants per walker  |
+  | ~fermi_num~     | ~uint64_t~                    | Number of number of fermions       |
+  | ~mo_index_list~ | ~mo_index[walk_num][det_num]~ | Index of MOs for each walker       |
+
+  Computed data:
+  
+  |-------------------+------------------------------------------+----------------------------------------------------------------------------------------|
+  | ~det_matrix_list~ | ~[walk_num][det_num][mo_num][fermi_num]~ | The slater matrix for each determinant of each walker.                                 |
+  |-------------------+------------------------------------------+----------------------------------------------------------------------------------------|
+  | ~det_vgl~         | ~[5][walk_num][det_num]~                 | Value, gradients, Laplacian of the MOs at electron positions                           |
+  | ~det_vgl_date~    | ~uint64_t~                               | Late modification date of Value, gradients, Laplacian of the MOs at electron positions |
+  |-------------------+------------------------------------------+----------------------------------------------------------------------------------------|
+  
+