diff --git a/org/qmckl_ao.org b/org/qmckl_ao.org
index 28dccb6..0b43b4c 100644
--- a/org/qmckl_ao.org
+++ b/org/qmckl_ao.org
@@ -255,21 +255,700 @@ qmckl_exit_code qmckl_init_ao_basis(qmckl_context context) {
    
 ** Access functions
 
-   #+begin_src c :comments org :tangle (eval h_private_func) :exports none
-char      qmckl_get_ao_basis_type             (const qmckl_context context);
-int64_t   qmckl_get_ao_basis_shell_num        (const qmckl_context context);
-int64_t   qmckl_get_ao_basis_prim_num         (const qmckl_context context);
-int64_t   qmckl_get_ao_basis_ao_num           (const qmckl_context context);
-int64_t*  qmckl_get_ao_basis_nucleus_index    (const qmckl_context context);
-int64_t*  qmckl_get_ao_basis_nucleus_shell_num(const qmckl_context context);
-int32_t*  qmckl_get_ao_basis_shell_ang_mom    (const qmckl_context context);
-int64_t*  qmckl_get_ao_basis_shell_prim_num   (const qmckl_context context);
-int64_t*  qmckl_get_ao_basis_shell_prim_index (const qmckl_context context);
-double*   qmckl_get_ao_basis_shell_factor     (const qmckl_context context);
-double*   qmckl_get_ao_basis_exponent         (const qmckl_context context);
-double*   qmckl_get_ao_basis_coefficient      (const qmckl_context context);
-double*   qmckl_get_ao_basis_prim_factor      (const qmckl_context context);
-double*   qmckl_get_ao_basis_ao_factor        (const qmckl_context context);
+   In the following functions, when an array is passed as an argument
+   the size of the array should be also passed to check that the array
+   is large enough to accept the data.
+
+   #+NAME:post
+   #+begin_src c :exports none
+if ( (ctx->ao_basis.uninitialized & mask) != 0) {
+  return NULL;
+}
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval h_func) :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_type (const qmckl_context context,
+                         char*    const type);
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_type (const qmckl_context context,
+                         char* const basis_type)
+{
+
+  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_CONTEXT,
+                           "qmckl_get_ao_basis_type",
+                           NULL);
+  }
+
+  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
+  assert (ctx != NULL);
+
+  int32_t mask = 1;
+
+  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
+    return qmckl_failwith( context,
+                           QMCKL_NOT_PROVIDED,
+                           "qmckl_get_ao_basis_type",
+                           NULL);
+
+  }
+
+  assert (ctx->ao_basis.type != (char) 0);
+
+  ,*basis_type = ctx->ao_basis.type;
+  return QMCKL_SUCCESS;
+}
+
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval h_func) :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_shell_num (const qmckl_context context,
+                              int64_t* const shell_num);
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_shell_num (const qmckl_context context,
+                              int64_t* const shell_num)
+{
+  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_CONTEXT,
+                           "qmckl_get_ao_basis_shell_factor",
+                           NULL);
+  }
+
+  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
+  assert (ctx != NULL);
+
+  int32_t mask = 1 << 1;
+
+  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
+    return qmckl_failwith( context,
+                           QMCKL_NOT_PROVIDED,
+                           "qmckl_get_ao_basis_shell_num",
+                           NULL);
+  }
+
+  assert (ctx->ao_basis.shell_num > (int64_t) 0);
+  ,*shell_num = ctx->ao_basis.shell_num;
+  return QMCKL_SUCCESS;
+}
+
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval h_func) :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_prim_num (const qmckl_context context,
+                             int64_t* const prim_num);
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_prim_num (const qmckl_context context,
+                             int64_t* const prim_num)
+{
+  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_CONTEXT,
+                           "qmckl_get_ao_basis_prim_num",
+                           NULL);
+  }
+
+  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
+  assert (ctx != NULL);
+
+  int32_t mask = 1 << 2;
+
+  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
+    return qmckl_failwith( context,
+                           QMCKL_NOT_PROVIDED,
+                           "qmckl_get_ao_basis_prim_num",
+                           NULL);
+  }
+
+  assert (ctx->ao_basis.prim_num > (int64_t) 0);
+
+  ,*prim_num = ctx->ao_basis.prim_num;
+  return QMCKL_SUCCESS;
+}
+
+   #+end_src
+   
+   #+begin_src c :comments org :tangle (eval h_func) :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_nucleus_shell_num (const qmckl_context context,
+                                      int64_t* const nucleus_shell_num,
+                                      const int64_t size_max);
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_nucleus_shell_num (const qmckl_context context,
+                                      int64_t* const nucleus_shell_num,
+                                      const int64_t size_max)
+{
+  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_CONTEXT,
+                           "qmckl_get_ao_basis_nucleus_shell_num",
+                           NULL);
+  }
+
+  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
+  assert (ctx != NULL);
+
+  int32_t mask = 1 << 3;
+
+  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
+    return qmckl_failwith( context,
+                           QMCKL_NOT_PROVIDED,
+                           "qmckl_get_ao_basis_nucleus_shell_num",
+                           NULL);
+  }
+
+  if (nucleus_shell_num == NULL) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_ARG_2,
+                           "qmckl_get_ao_basis_nucleus_shell_num",
+                           "NULL pointer");
+  }
+
+  if (size_max < ctx->nucleus.num) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_ARG_3,
+                           "qmckl_get_ao_basis_nucleus_shell_num",
+                           "Array too small. Expected nucl_num");
+  }
+
+  assert (ctx->ao_basis.nucleus_shell_num != NULL);
+  memcpy(nucleus_shell_num, ctx->ao_basis.nucleus_shell_num, ctx->nucleus.num * sizeof(int64_t));
+  return QMCKL_SUCCESS;
+}
+
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval h_func) :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_nucleus_index (const qmckl_context context,
+                                  int64_t* const nucleus_index,
+                                  const int64_t size_max);
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_nucleus_index (const qmckl_context context,
+                                  int64_t* const nucleus_index,
+                                  const int64_t size_max)
+{
+  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_CONTEXT,
+                           "qmckl_get_ao_basis_nucleus_index",
+                           NULL);
+  }
+
+  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
+  assert (ctx != NULL);
+
+  int32_t mask = 1 << 4;
+
+  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
+    return qmckl_failwith( context,
+                           QMCKL_NOT_PROVIDED,
+                           "qmckl_get_ao_basis_nucleus_index",
+                           NULL);
+  }
+
+  if (nucleus_index == NULL) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_ARG_2,
+                           "qmckl_get_ao_basis_nucleus_index",
+                           "NULL pointer");
+  }
+
+  if (size_max < ctx->nucleus.num) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_ARG_3,
+                           "qmckl_get_ao_basis_nucleus_index",
+                           "Array too small. Expected shell_num");
+  }
+
+  assert (ctx->ao_basis.nucleus_index != NULL);
+  memcpy(nucleus_index, ctx->ao_basis.nucleus_index, ctx->nucleus.num * sizeof(int64_t));
+  return QMCKL_SUCCESS;
+}
+
+
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval h_func) :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_shell_ang_mom (const qmckl_context context,
+                                  int32_t* const shell_ang_mom,
+                                  const int64_t size_max);
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_shell_ang_mom (const qmckl_context context,
+                                  int32_t* const shell_ang_mom,
+                                  const int64_t size_max)
+{
+  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_CONTEXT,
+                           "qmckl_get_ao_basis_shell_ang_mom",
+                           NULL);
+  }
+
+  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
+  assert (ctx != NULL);
+
+  int32_t mask = 1 << 5;
+
+  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
+    return qmckl_failwith( context,
+                           QMCKL_NOT_PROVIDED,
+                           "qmckl_get_ao_basis_shell_ang_mom",
+                           NULL);
+  }
+
+  if (shell_ang_mom == NULL) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_ARG_2,
+                           "qmckl_get_ao_basis_shell_ang_mom",
+                           "NULL pointer");
+  }
+
+  if (size_max < ctx->ao_basis.shell_num) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_ARG_3,
+                           "qmckl_get_ao_basis_shell_ang_mom",
+                           "Array too small. Expected shell_num");
+  }
+
+  assert (ctx->ao_basis.shell_ang_mom != NULL);
+  memcpy(shell_ang_mom, ctx->ao_basis.shell_ang_mom, ctx->ao_basis.shell_num * sizeof(int32_t));
+  return QMCKL_SUCCESS;
+}
+
+
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval h_func) :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_shell_prim_num (const qmckl_context context,
+                                   int64_t* const shell_prim_num,
+                                   const int64_t size_max);
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_shell_prim_num (const qmckl_context context,
+                                   int64_t* const shell_prim_num,
+                                   const int64_t size_max)
+{
+  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_CONTEXT,
+                           "qmckl_get_ao_basis_shell_prim_num",
+                           NULL);
+  }
+
+  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
+  assert (ctx != NULL);
+
+  int32_t mask = 1 << 6;
+
+  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
+    return qmckl_failwith( context,
+                           QMCKL_NOT_PROVIDED,
+                           "qmckl_get_ao_basis_shell_prim_num",
+                           NULL);
+  }
+
+  if (shell_prim_num == NULL) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_ARG_2,
+                           "qmckl_get_ao_basis_shell_prim_num",
+                           "NULL pointer");
+  }
+
+  if (size_max < ctx->ao_basis.shell_num) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_ARG_3,
+                           "qmckl_get_ao_basis_shell_prim_num",
+                           "Array too small. Expected shell_num");
+  }
+
+  assert (ctx->ao_basis.shell_prim_num != NULL);
+  memcpy(shell_prim_num, ctx->ao_basis.shell_prim_num, ctx->ao_basis.shell_num * sizeof(int64_t));
+  return QMCKL_SUCCESS;
+}
+
+
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval h_func) :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_shell_prim_index (const qmckl_context context,
+                                     int64_t* const shell_prim_index,
+                                     const int64_t size_max);
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_shell_prim_index (const qmckl_context context,
+                                     int64_t* const shell_prim_index,
+                                     const int64_t size_max)
+{
+  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_CONTEXT,
+                           "qmckl_get_ao_basis_shell_prim_index",
+                           NULL);
+  }
+
+  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
+  assert (ctx != NULL);
+
+  int32_t mask = 1 << 7;
+
+  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
+    return qmckl_failwith( context,
+                           QMCKL_NOT_PROVIDED,
+                           "qmckl_get_ao_basis_shell_prim_index",
+                           NULL);
+  }
+
+  if (shell_prim_index == NULL) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_ARG_2,
+                           "qmckl_get_ao_basis_shell_prim_index",
+                           "NULL pointer");
+  }
+
+  if (size_max < ctx->ao_basis.shell_num) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_ARG_3,
+                           "qmckl_get_ao_basis_shell_prim_index",
+                           "Array too small. Expected shell_num");
+  }
+
+  assert (ctx->ao_basis.shell_prim_index != NULL);
+  memcpy(shell_prim_index, ctx->ao_basis.shell_prim_index, ctx->ao_basis.shell_num * sizeof(int64_t));
+  return QMCKL_SUCCESS;
+}
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval h_func) :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_shell_factor (const qmckl_context context,
+                                 double*  const shell_factor,
+                                 const int64_t size_max);
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_shell_factor (const qmckl_context context,
+                                 double* const shell_factor,
+                                 const int64_t size_max)
+{
+  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_CONTEXT,
+                           "qmckl_get_ao_basis_shell_factor",
+                           NULL);
+  }
+
+  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
+  assert (ctx != NULL);
+
+  int32_t mask = 1 << 8;
+
+  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
+    return qmckl_failwith( context,
+                           QMCKL_NOT_PROVIDED,
+                           "qmckl_get_ao_basis_shell_factor",
+                           NULL);
+  }
+
+  if (shell_factor == NULL) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_ARG_2,
+                           "qmckl_get_ao_basis_shell_factor",
+                           "NULL pointer");
+  }
+
+  if (size_max < ctx->ao_basis.shell_num) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_ARG_3,
+                           "qmckl_get_ao_basis_shell_factor",
+                           "Array too small. Expected shell_num");
+  }
+
+  assert (ctx->ao_basis.shell_factor != NULL);
+  memcpy(shell_factor, ctx->ao_basis.shell_factor, ctx->ao_basis.shell_num * sizeof(double));
+  return QMCKL_SUCCESS;
+}
+
+
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval h_func) :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_exponent (const qmckl_context context,
+                             double*  const exponent,
+                             const int64_t size_max);
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_exponent (const qmckl_context context,
+                             double* const exponent,
+                             const int64_t size_max)
+{
+  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_CONTEXT,
+                           "qmckl_get_ao_basis_exponent",
+                           NULL);
+  }
+
+  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
+  assert (ctx != NULL);
+
+  int32_t mask = 1 << 9;
+
+  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
+    return qmckl_failwith( context,
+                           QMCKL_NOT_PROVIDED,
+                           "qmckl_get_ao_basis_exponent",
+                           NULL);
+  }
+
+  if (exponent == NULL) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_ARG_2,
+                           "qmckl_get_ao_basis_exponent",
+                           "NULL pointer");
+  }
+
+  if (size_max < ctx->ao_basis.prim_num) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_ARG_3,
+                           "qmckl_get_ao_basis_exponent",
+                           "Array too small. Expected prim_num");
+  }
+
+  assert (ctx->ao_basis.exponent != NULL);
+  memcpy(exponent, ctx->ao_basis.exponent, ctx->ao_basis.prim_num * sizeof(double));
+  return QMCKL_SUCCESS;
+}
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval h_func) :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_coefficient (const qmckl_context context,
+                                double*  const coefficient,
+                                const int64_t size_max);
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_coefficient (const qmckl_context context,
+                                double* const coefficient,
+                                const int64_t size_max)
+{
+  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_CONTEXT,
+                           "qmckl_get_ao_basis_coefficient",
+                           NULL);
+  }
+
+  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
+  assert (ctx != NULL);
+
+  int32_t mask = 1 << 10;
+
+  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
+    return qmckl_failwith( context,
+                           QMCKL_NOT_PROVIDED,
+                           "qmckl_get_ao_basis_coefficient",
+                           NULL);
+  }
+
+  if (coefficient == NULL) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_ARG_2,
+                           "qmckl_get_ao_basis_coefficient",
+                           "NULL pointer");
+  }
+
+  if (size_max < ctx->ao_basis.prim_num) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_ARG_3,
+                           "qmckl_get_ao_basis_coefficient",
+                           "Array too small. Expected prim_num");
+  }
+  assert (ctx->ao_basis.coefficient != NULL);
+  memcpy(coefficient, ctx->ao_basis.coefficient, ctx->ao_basis.prim_num * sizeof(double));
+  return QMCKL_SUCCESS;
+}
+
+
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval h_func) :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_prim_factor (const qmckl_context context,
+                                double*  const prim_factor,
+                                const int64_t size_max);
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_prim_factor (const qmckl_context context,
+                                double* const prim_factor,
+                                const int64_t size_max)
+{
+  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_CONTEXT,
+                           "qmckl_get_ao_basis_prim_factor",
+                           NULL);
+  }
+
+  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
+  assert (ctx != NULL);
+
+  int32_t mask = 1 << 11;
+
+  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
+    return qmckl_failwith( context,
+                           QMCKL_NOT_PROVIDED,
+                           "qmckl_get_ao_basis_prim_factor",
+                           NULL);
+  }
+
+  if (prim_factor == NULL) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_ARG_2,
+                           "qmckl_get_ao_basis_prim_factor",
+                           "NULL pointer");
+  }
+
+  if (size_max < ctx->ao_basis.prim_num) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_ARG_3,
+                           "qmckl_get_ao_basis_prim_factor",
+                           "Array too small. Expected prim_num");
+  }
+
+  assert (ctx->ao_basis.prim_factor != NULL);
+  memcpy(prim_factor, ctx->ao_basis.prim_factor, ctx->ao_basis.prim_num * sizeof(double));
+  return QMCKL_SUCCESS;
+}
+
+
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval h_func) :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_ao_num (const qmckl_context context,
+                           int64_t* const ao_num);
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_ao_num (const qmckl_context context,
+                           int64_t* const ao_num)
+{
+  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_CONTEXT,
+                           "qmckl_get_ao_basis_ao_num",
+                           NULL);
+  }
+
+  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
+  assert (ctx != NULL);
+
+  int32_t mask = 1 << 12;
+
+  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
+    return qmckl_failwith( context,
+                           QMCKL_NOT_PROVIDED,
+                           "qmckl_get_ao_basis_ao_num",
+                           NULL);
+  }
+
+  assert (ctx->ao_basis.ao_num > (int64_t) 0);
+
+  *ao_num = ctx->ao_basis.ao_num;
+  return QMCKL_SUCCESS;
+}
+
+
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
+qmckl_exit_code
+qmckl_get_ao_basis_ao_factor (const qmckl_context context,
+                              double* const ao_factor,
+                              const int64_t size_max)
+{
+  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_CONTEXT,
+                           "qmckl_get_ao_basis_ao_factor",
+                           NULL);
+  }
+
+  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
+  assert (ctx != NULL);
+
+  int32_t mask = 1 << 13;
+
+  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
+    return qmckl_failwith( context,
+                           QMCKL_NOT_PROVIDED,
+                           "qmckl_get_ao_basis_ao_factor",
+                           NULL);
+  }
+
+  if (ao_factor == NULL) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_ARG_2,
+                           "qmckl_get_ao_basis_ao_factor",
+                           "NULL pointer");
+  }
+
+  if (size_max < ctx->ao_basis.ao_num) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_ARG_3,
+                           "qmckl_get_ao_basis_ao_factor",
+                           "Array too small. Expected ao_num");
+  }
+
+  assert (ctx->ao_basis.ao_factor != NULL);
+  memcpy(ao_factor, ctx->ao_basis.ao_factor, ctx->ao_basis.ao_num * sizeof(double));
+  return QMCKL_SUCCESS;
+}
+   #+end_src
+
+   #+begin_src c :comments org :tangle (eval h_func) :exports none
+qmckl_exit_code qmckl_get_ao_basis_ao_factor (const qmckl_context context,
+                                              double*  const ao_factor,
+                                              const int64_t size_max);
    #+end_src
 
    When all the data for the AOs have been provided, the following
@@ -279,281 +958,7 @@ double*   qmckl_get_ao_basis_ao_factor        (const qmckl_context context);
 bool      qmckl_ao_basis_provided           (const qmckl_context context);
    #+end_src
 
-   #+NAME:post
-   #+begin_src c :exports none
-if ( (ctx->ao_basis.uninitialized & mask) != 0) {
-  return NULL;
-}
-   #+end_src
-
    #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
-char qmckl_get_ao_basis_type (const qmckl_context context) {
-
-  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
-    return (char) 0;
-  }
-
-  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
-  assert (ctx != NULL);
-
-  int32_t mask = 1;
-
-  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
-    return (char) 0;
-  }
-
-  assert (ctx->ao_basis.type != (char) 0);
-  return ctx->ao_basis.type;
-}
-
-
-int64_t qmckl_get_ao_basis_shell_num (const qmckl_context context) {
-  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
-    return (int64_t) 0;
-  }
-
-  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
-  assert (ctx != NULL);
-
-  int32_t mask = 1 << 1;
-
-  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
-    return (int64_t) 0;
-  }
-
-  assert (ctx->ao_basis.shell_num > (int64_t) 0);
-  return ctx->ao_basis.shell_num;
-}
-
-
-int64_t qmckl_get_ao_basis_prim_num (const qmckl_context context) {
-  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
-    return (int64_t) 0;
-  }
-
-  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
-  assert (ctx != NULL);
-
-  int32_t mask = 1 << 2;
-
-  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
-    return (int64_t) 0;
-  }
-
-  assert (ctx->ao_basis.prim_num > (int64_t) 0);
-  return ctx->ao_basis.prim_num;
-}
-
-
-int64_t* qmckl_get_ao_basis_nucleus_shell_num (const qmckl_context context) {
-  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
-    return NULL;
-  }
-
-  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
-  assert (ctx != NULL);
-
-  int32_t mask = 1 << 3;
-
-  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
-    return NULL;
-  }
-
-  assert (ctx->ao_basis.nucleus_shell_num != NULL);
-  return ctx->ao_basis.nucleus_shell_num ;
-}
-
-int64_t* qmckl_get_ao_basis_nucleus_index (const qmckl_context context) {
-  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
-    return NULL;
-  }
-
-  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
-  assert (ctx != NULL);
-
-  int32_t mask = 1 << 4;
-
-  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
-    return NULL;
-  }
-
-  assert (ctx->ao_basis.nucleus_index != NULL);
-  return ctx->ao_basis.nucleus_index ;
-}
-
-
-int32_t* qmckl_get_ao_basis_shell_ang_mom (const qmckl_context context) {
-  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
-    return NULL;
-  }
-
-  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
-  assert (ctx != NULL);
-
-  int32_t mask = 1 << 5;
-
-  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
-    return NULL;
-  }
-
-  assert (ctx->ao_basis.shell_ang_mom != NULL);
-  return ctx->ao_basis.shell_ang_mom;
-}
-
-
-int64_t* qmckl_get_ao_basis_shell_prim_num (const qmckl_context context) {
-  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
-    return NULL;
-  }
-
-  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
-  assert (ctx != NULL);
-
-  int32_t mask = 1 << 6;
-
-  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
-    return NULL;
-  }
-
-  assert (ctx->ao_basis.shell_prim_num != NULL);
-  return ctx->ao_basis.shell_prim_num;
-}
-
-
-int64_t* qmckl_get_ao_basis_shell_prim_index (const qmckl_context context) {
-  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
-    return NULL;
-  }
-
-  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
-  assert (ctx != NULL);
-
-  int32_t mask = 1 << 7;
-
-  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
-    return NULL;
-  }
-
-  assert (ctx->ao_basis.shell_prim_index != NULL);
-  return ctx->ao_basis.shell_prim_index;
-}
-
-
-double* qmckl_get_ao_basis_shell_factor (const qmckl_context context) {
-  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
-    return NULL;
-  }
-
-  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
-  assert (ctx != NULL);
-
-  int32_t mask = 1 << 8;
-
-  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
-    return NULL;
-  }
-
-  assert (ctx->ao_basis.shell_factor != NULL);
-  return ctx->ao_basis.shell_factor;
-}
-
-
-double* qmckl_get_ao_basis_exponent (const qmckl_context context) {
-  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
-    return NULL;
-  }
-
-  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
-  assert (ctx != NULL);
-
-
-  int32_t mask = 1 << 9;
-
-  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
-    return NULL;
-  }
-
-  assert (ctx->ao_basis.exponent != NULL);
-  return ctx->ao_basis.exponent;
-}
-
-
-double* qmckl_get_ao_basis_coefficient (const qmckl_context context) {
-  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
-    return NULL;
-  }
-
-  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
-  assert (ctx != NULL);
-
-  int32_t mask = 1 << 10;
-
-  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
-    return NULL;
-  }
-
-  assert (ctx->ao_basis.coefficient != NULL);
-  return ctx->ao_basis.coefficient;
-}
-
-
-double* qmckl_get_ao_basis_prim_factor (const qmckl_context context) {
-  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
-    return NULL;
-  }
-
-  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
-  assert (ctx != NULL);
-
-  int32_t mask = 1 << 11;
-
-  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
-    return NULL;
-  }
-
-  assert (ctx->ao_basis.prim_factor != NULL);
-  return ctx->ao_basis.prim_factor;
-}
-
-
-int64_t qmckl_get_ao_basis_ao_num (const qmckl_context context) {
-  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
-    return (int64_t) 0;
-  }
-
-  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
-  assert (ctx != NULL);
-
-  int32_t mask = 1 << 12;
-
-  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
-    return (int64_t) 0;
-  }
-
-  assert (ctx->ao_basis.ao_num > (int64_t) 0);
-  return ctx->ao_basis.ao_num;
-}
-
-
-double* qmckl_get_ao_basis_ao_factor (const qmckl_context context) {
-  if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
-    return NULL;
-  }
-
-  qmckl_context_struct* const ctx = (qmckl_context_struct* const) context;
-  assert (ctx != NULL);
-
-  int32_t mask = 1 << 13;
-
-  if ( (ctx->ao_basis.uninitialized & mask) != 0) {
-    return NULL;
-  }
-
-  assert (ctx->ao_basis.ao_factor != NULL);
-  return ctx->ao_basis.ao_factor;
-}
-
-
 bool qmckl_ao_basis_provided(const qmckl_context context) {
 
   if (qmckl_context_check(context) == QMCKL_NULL_CONTEXT) {
@@ -565,9 +970,6 @@ bool qmckl_ao_basis_provided(const qmckl_context context) {
 
   return ctx->ao_basis.provided;
 }
-
-
-
    #+end_src
 
 ** Initialization functions
@@ -630,8 +1032,9 @@ qmckl_exit_code qmckl_set_ao_basis_type(qmckl_context context, const char t) {
 
   <<post2>>
 }
+   #+end_src
 
-
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
 qmckl_exit_code qmckl_set_ao_basis_shell_num(qmckl_context context, const int64_t shell_num) {
   <<pre2>>
 
@@ -642,7 +1045,7 @@ qmckl_exit_code qmckl_set_ao_basis_shell_num(qmckl_context context, const int64_
                            "shell_num <= 0");
   }
 
-  int64_t prim_num = qmckl_get_ao_basis_prim_num(context);
+  const int64_t prim_num = ctx->ao_basis.prim_num;
 
   if (0L < prim_num && prim_num < shell_num) {
     return qmckl_failwith( context,
@@ -656,8 +1059,9 @@ qmckl_exit_code qmckl_set_ao_basis_shell_num(qmckl_context context, const int64_
 
   <<post2>>
 }
+   #+end_src
 
-
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
 qmckl_exit_code  qmckl_set_ao_basis_prim_num(qmckl_context context, const int64_t prim_num) {
   <<pre2>>
 
@@ -668,7 +1072,14 @@ qmckl_exit_code  qmckl_set_ao_basis_prim_num(qmckl_context context, const int64_
                            "prim_num must be positive");
   }
 
-  int64_t shell_num = qmckl_get_ao_basis_shell_num(context);
+  const int64_t shell_num = ctx->ao_basis.shell_num;
+
+  if (shell_num <= 0L) {
+    return qmckl_failwith( context,
+                           QMCKL_FAILURE,
+                           "qmckl_set_ao_basis_shell_num",
+                           "shell_num is not set");
+  }
 
   if (prim_num < shell_num) {
     return qmckl_failwith( context,
@@ -682,15 +1093,18 @@ qmckl_exit_code  qmckl_set_ao_basis_prim_num(qmckl_context context, const int64_
 
   <<post2>>
 }
+   #+end_src
 
-
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
 qmckl_exit_code  qmckl_set_ao_basis_nucleus_shell_num(qmckl_context context, const int64_t* nucleus_shell_num) {
   <<pre2>>
+  qmckl_exit_code rc = QMCKL_FAILURE;
 
   int32_t mask = 1 << 3;
 
-  const int64_t shell_num = qmckl_get_ao_basis_shell_num(context);
-  if (shell_num == 0L) {
+  const int64_t shell_num = ctx->ao_basis.shell_num;
+
+  if (shell_num <= 0L) {
     return qmckl_failwith( context,
                            QMCKL_FAILURE,
                            "qmckl_set_ao_basis_nucleus_shell_num",
@@ -698,7 +1112,7 @@ qmckl_exit_code  qmckl_set_ao_basis_nucleus_shell_num(qmckl_context context, con
   }
 
   if (ctx->ao_basis.nucleus_shell_num != NULL) {
-    qmckl_exit_code rc = qmckl_free(context, ctx->ao_basis.nucleus_shell_num);
+    rc = qmckl_free(context, ctx->ao_basis.nucleus_shell_num);
     if (rc != QMCKL_SUCCESS) {
       return qmckl_failwith( context, rc,
                              "qmckl_set_ao_basis_nucleus_shell_num",
@@ -723,14 +1137,18 @@ qmckl_exit_code  qmckl_set_ao_basis_nucleus_shell_num(qmckl_context context, con
 
   <<post2>>
 }
+   #+end_src
 
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
 qmckl_exit_code  qmckl_set_ao_basis_nucleus_index(qmckl_context context, const int64_t* nucleus_index) {
   <<pre2>>
+  qmckl_exit_code rc = QMCKL_FAILURE;
 
   int32_t mask = 1 << 4;
 
-  const int64_t shell_num = qmckl_get_ao_basis_shell_num(context);
-  if (shell_num == 0L) {
+  const int64_t shell_num = ctx->ao_basis.shell_num;
+
+  if (shell_num <= 0L) {
     return qmckl_failwith( context,
                            QMCKL_FAILURE,
                            "qmckl_set_ao_basis_nucleus_index",
@@ -738,7 +1156,7 @@ qmckl_exit_code  qmckl_set_ao_basis_nucleus_index(qmckl_context context, const i
   }
 
   if (ctx->ao_basis.nucleus_index != NULL) {
-    qmckl_exit_code rc = qmckl_free(context, ctx->ao_basis.nucleus_index);
+    rc = qmckl_free(context, ctx->ao_basis.nucleus_index);
     if (rc != QMCKL_SUCCESS) {
       return qmckl_failwith( context, rc,
                              "qmckl_set_ao_basis_nucleus_index",
@@ -763,14 +1181,17 @@ qmckl_exit_code  qmckl_set_ao_basis_nucleus_index(qmckl_context context, const i
 
   <<post2>>
 }
+   #+end_src
 
-
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
 qmckl_exit_code  qmckl_set_ao_basis_shell_ang_mom(qmckl_context context, const int32_t* shell_ang_mom) {
   <<pre2>>
+  qmckl_exit_code rc = QMCKL_FAILURE;
 
   int32_t mask = 1 << 5;
 
-  const int64_t shell_num = qmckl_get_ao_basis_shell_num(context);
+  const int64_t shell_num = ctx->ao_basis.shell_num;
+
   if (shell_num == 0L) {
     return qmckl_failwith( context,
                            QMCKL_FAILURE,
@@ -779,7 +1200,7 @@ qmckl_exit_code  qmckl_set_ao_basis_shell_ang_mom(qmckl_context context, const i
   }
 
   if (ctx->ao_basis.shell_ang_mom != NULL) {
-    qmckl_exit_code rc = qmckl_free(context, ctx->ao_basis.shell_ang_mom);
+    rc = qmckl_free(context, ctx->ao_basis.shell_ang_mom);
     if (rc != QMCKL_SUCCESS) {
       return qmckl_failwith( context, rc,
                              "qmckl_set_ao_basis_shell_ang_mom",
@@ -805,15 +1226,18 @@ qmckl_exit_code  qmckl_set_ao_basis_shell_ang_mom(qmckl_context context, const i
 
   <<post2>>
 }
+   #+end_src
 
-
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
 qmckl_exit_code  qmckl_set_ao_basis_shell_prim_num(qmckl_context context, const int64_t* shell_prim_num) {
   <<pre2>>
+  qmckl_exit_code rc = QMCKL_FAILURE;
 
   int32_t mask = 1 << 6;
 
-  const int64_t shell_num = qmckl_get_ao_basis_shell_num(context);
-  if (shell_num == 0L) {
+  const int64_t shell_num = ctx->ao_basis.shell_num;
+
+  if (shell_num <= 0L) {
     return qmckl_failwith( context,
                            QMCKL_FAILURE,
                            "qmckl_set_ao_basis_shell_prim_num",
@@ -821,7 +1245,7 @@ qmckl_exit_code  qmckl_set_ao_basis_shell_prim_num(qmckl_context context, const
   }
 
   if (ctx->ao_basis.shell_prim_num != NULL) {
-    qmckl_exit_code rc = qmckl_free(context, ctx->ao_basis.shell_prim_num);
+    rc = qmckl_free(context, ctx->ao_basis.shell_prim_num);
     if (rc != QMCKL_SUCCESS) {
       return qmckl_failwith( context, rc,
                              "qmckl_set_ao_basis_shell_prim_num",
@@ -847,15 +1271,18 @@ qmckl_exit_code  qmckl_set_ao_basis_shell_prim_num(qmckl_context context, const
 
   <<post2>>
 }
+   #+end_src
 
-
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
 qmckl_exit_code  qmckl_set_ao_basis_shell_prim_index(qmckl_context context, const int64_t* shell_prim_index) {
   <<pre2>>
+  qmckl_exit_code rc = QMCKL_FAILURE;
 
   int32_t mask = 1 << 7;
 
-  const int64_t shell_num = qmckl_get_ao_basis_shell_num(context);
-  if (shell_num == 0L) {
+  const int64_t shell_num = ctx->ao_basis.shell_num;
+
+  if (shell_num <= 0L) {
     return qmckl_failwith( context,
                            QMCKL_FAILURE,
                            "qmckl_set_ao_basis_shell_prim_index",
@@ -863,7 +1290,7 @@ qmckl_exit_code  qmckl_set_ao_basis_shell_prim_index(qmckl_context context, cons
   }
 
   if (ctx->ao_basis.shell_prim_index != NULL) {
-    qmckl_exit_code rc = qmckl_free(context, ctx->ao_basis.shell_prim_index);
+    rc = qmckl_free(context, ctx->ao_basis.shell_prim_index);
     if (rc != QMCKL_SUCCESS) {
       return qmckl_failwith( context, rc,
                              "qmckl_set_ao_basis_shell_prim_index",
@@ -888,15 +1315,18 @@ qmckl_exit_code  qmckl_set_ao_basis_shell_prim_index(qmckl_context context, cons
 
   <<post2>>
 }
+   #+end_src
 
-
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
 qmckl_exit_code  qmckl_set_ao_basis_shell_factor(qmckl_context context, const double* shell_factor) {
   <<pre2>>
+  qmckl_exit_code rc = QMCKL_FAILURE;
 
   int32_t mask = 1 << 8;
 
-  const int64_t shell_num = qmckl_get_ao_basis_shell_num(context);
-  if (shell_num == 0L) {
+  const int64_t shell_num = ctx->ao_basis.shell_num;
+
+  if (shell_num <= 0L) {
     return qmckl_failwith( context,
                            QMCKL_FAILURE,
                            "qmckl_set_ao_basis_shell_factor",
@@ -905,7 +1335,7 @@ qmckl_exit_code  qmckl_set_ao_basis_shell_factor(qmckl_context context, const do
 
 
   if (ctx->ao_basis.shell_factor != NULL) {
-    qmckl_exit_code rc = qmckl_free(context, ctx->ao_basis.shell_factor);
+    rc = qmckl_free(context, ctx->ao_basis.shell_factor);
     if (rc != QMCKL_SUCCESS) {
       return qmckl_failwith( context, rc,
                              "qmckl_set_ao_basis_shell_factor",
@@ -930,14 +1360,18 @@ qmckl_exit_code  qmckl_set_ao_basis_shell_factor(qmckl_context context, const do
 
   <<post2>>
 }
+   #+end_src
 
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
 qmckl_exit_code  qmckl_set_ao_basis_exponent(qmckl_context context, const double* exponent) {
   <<pre2>>
+  qmckl_exit_code rc = QMCKL_FAILURE;
 
   int32_t mask = 1 << 9;
 
-  const int64_t prim_num = qmckl_get_ao_basis_prim_num(context);
-  if (prim_num == 0L) {
+  const int64_t prim_num = ctx->ao_basis.prim_num;
+
+  if (prim_num <= 0L) {
     return qmckl_failwith( context,
                            QMCKL_FAILURE,
                            "qmckl_set_ao_basis_exponent",
@@ -945,7 +1379,7 @@ qmckl_exit_code  qmckl_set_ao_basis_exponent(qmckl_context context, const double
   }
 
   if (ctx->ao_basis.exponent != NULL) {
-    qmckl_exit_code rc = qmckl_free(context, ctx->ao_basis.exponent);
+    rc = qmckl_free(context, ctx->ao_basis.exponent);
     if (rc != QMCKL_SUCCESS) {
       return qmckl_failwith( context, rc,
                              "qmckl_set_ao_basis_exponent",
@@ -970,14 +1404,18 @@ qmckl_exit_code  qmckl_set_ao_basis_exponent(qmckl_context context, const double
 
   <<post2>>
 }
+   #+end_src
 
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
 qmckl_exit_code  qmckl_set_ao_basis_coefficient(qmckl_context context, const double* coefficient) {
   <<pre2>>
+  qmckl_exit_code rc = QMCKL_FAILURE;
 
   int32_t mask = 1 << 10;
 
-  const int64_t prim_num = qmckl_get_ao_basis_prim_num(context);
-  if (prim_num == 0L) {
+  const int64_t prim_num = ctx->ao_basis.prim_num;
+
+  if (prim_num <= 0L) {
     return qmckl_failwith( context,
                            QMCKL_FAILURE,
                            "qmckl_set_ao_basis_coefficient",
@@ -985,7 +1423,7 @@ qmckl_exit_code  qmckl_set_ao_basis_coefficient(qmckl_context context, const dou
   }
 
   if (ctx->ao_basis.coefficient != NULL) {
-    qmckl_exit_code rc = qmckl_free(context, ctx->ao_basis.coefficient);
+    rc = qmckl_free(context, ctx->ao_basis.coefficient);
     if (rc != QMCKL_SUCCESS) {
       return qmckl_failwith( context, rc,
                              "qmckl_set_ao_basis_coefficient",
@@ -1010,15 +1448,18 @@ qmckl_exit_code  qmckl_set_ao_basis_coefficient(qmckl_context context, const dou
 
   <<post2>>
 }
+   #+end_src
 
-
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
 qmckl_exit_code  qmckl_set_ao_basis_prim_factor(qmckl_context context, const double* prim_factor) {
   <<pre2>>
+  qmckl_exit_code rc = QMCKL_FAILURE;
 
   int32_t mask = 1 << 11;
 
-  const int64_t prim_num = qmckl_get_ao_basis_prim_num(context);
-  if (prim_num == 0L) {
+  const int64_t prim_num = ctx->ao_basis.prim_num;
+
+  if (prim_num <= 0L) {
     return qmckl_failwith( context,
                            QMCKL_FAILURE,
                            "qmckl_set_ao_basis_prim_factor",
@@ -1027,7 +1468,7 @@ qmckl_exit_code  qmckl_set_ao_basis_prim_factor(qmckl_context context, const dou
 
 
   if (ctx->ao_basis.prim_factor != NULL) {
-    qmckl_exit_code rc = qmckl_free(context, ctx->ao_basis.prim_factor);
+    rc = qmckl_free(context, ctx->ao_basis.prim_factor);
     if (rc != QMCKL_SUCCESS) {
       return qmckl_failwith( context, rc,
                              "qmckl_set_ao_basis_prim_factor",
@@ -1052,8 +1493,9 @@ qmckl_exit_code  qmckl_set_ao_basis_prim_factor(qmckl_context context, const dou
 
   <<post2>>
 }
+   #+end_src
 
-
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
 qmckl_exit_code  qmckl_set_ao_basis_ao_num(qmckl_context context, const int64_t ao_num) {
   <<pre2>>
 
@@ -1064,7 +1506,13 @@ qmckl_exit_code  qmckl_set_ao_basis_ao_num(qmckl_context context, const int64_t
                            "ao_num must be positive");
   }
 
-  int64_t shell_num = qmckl_get_ao_basis_shell_num(context);
+  const int64_t shell_num = ctx->ao_basis.shell_num;
+  if (shell_num <= 0L) {
+    return qmckl_failwith( context,
+                           QMCKL_INVALID_ARG_2,
+                           "qmckl_set_ao_basis_shell_num",
+                           "shell_num is not set");
+  }
 
   if (ao_num < shell_num) {
     return qmckl_failwith( context,
@@ -1078,15 +1526,18 @@ qmckl_exit_code  qmckl_set_ao_basis_ao_num(qmckl_context context, const int64_t
 
   <<post2>>
 }
+   #+end_src
 
-
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
 qmckl_exit_code  qmckl_set_ao_basis_ao_factor(qmckl_context context, const double* ao_factor) {
   <<pre2>>
+  qmckl_exit_code rc = QMCKL_FAILURE;
 
   int32_t mask = 1 << 13;
 
-  const int64_t ao_num = qmckl_get_ao_basis_ao_num(context);
-  if (ao_num == 0L) {
+  const int64_t ao_num = ctx->ao_basis.ao_num;
+
+  if (ao_num <= 0L) {
     return qmckl_failwith( context,
                            QMCKL_FAILURE,
                            "qmckl_set_ao_basis_ao_factor",
@@ -1095,7 +1546,7 @@ qmckl_exit_code  qmckl_set_ao_basis_ao_factor(qmckl_context context, const doubl
 
 
   if (ctx->ao_basis.ao_factor != NULL) {
-    qmckl_exit_code rc = qmckl_free(context, ctx->ao_basis.ao_factor);
+    rc = qmckl_free(context, ctx->ao_basis.ao_factor);
     if (rc != QMCKL_SUCCESS) {
       return qmckl_failwith( context, rc,
                              "qmckl_set_ao_basis_ao_factor",
@@ -1120,8 +1571,9 @@ qmckl_exit_code  qmckl_set_ao_basis_ao_factor(qmckl_context context, const doubl
 
   <<post2>>
 }
+   #+end_src
 
-
+   #+begin_src c :comments org :tangle (eval c) :noweb yes :exports none
 qmckl_exit_code qmckl_set_ao_basis_cartesian(qmckl_context context, const bool t) {
   <<pre2>>
 
@@ -1536,64 +1988,97 @@ double  *  ao_factor_test        ;
 char    typ_test ;
 
 
-typ_test = qmckl_get_ao_basis_type (context);
+rc = qmckl_get_ao_basis_type (context, &typ_test);
+assert (rc == QMCKL_SUCCESS);
 assert(typ == typ_test);
 
-shell_num_test = qmckl_get_ao_basis_shell_num (context);
+rc = qmckl_get_ao_basis_shell_num (context, &shell_num_test);
+assert (rc == QMCKL_SUCCESS);
 assert(shell_num == shell_num_test);
 
-prim_num_test = qmckl_get_ao_basis_prim_num (context);
+rc = qmckl_get_ao_basis_prim_num (context, &prim_num_test);
+assert (rc == QMCKL_SUCCESS);
 assert(prim_num == prim_num_test);
 
-nucleus_index_test = qmckl_get_ao_basis_nucleus_index (context);
+nucleus_index_test = (int64_t*) malloc (nucl_num * sizeof(int64_t));
+rc = qmckl_get_ao_basis_nucleus_index (context, nucleus_index_test, nucl_num);
+assert (rc == QMCKL_SUCCESS);
 for (int64_t i=0 ; i < nucl_num ; ++i) {
   assert(nucleus_index_test[i] == nucleus_index[i]);
  }
+free(nucleus_index_test);
+
+nucleus_shell_num_test = (int64_t*) malloc ( nucl_num * sizeof(int64_t));
+rc = qmckl_get_ao_basis_nucleus_shell_num (context, nucleus_shell_num_test, nucl_num);
+assert (rc == QMCKL_SUCCESS);
 
-nucleus_shell_num_test = qmckl_get_ao_basis_nucleus_shell_num (context);
 for (int64_t i=0 ; i < nucl_num ; ++i) {
   assert(nucleus_shell_num_test[i] == nucleus_shell_num[i]);
  }
 
-shell_ang_mom_test = qmckl_get_ao_basis_shell_ang_mom (context);
+shell_ang_mom_test = (int32_t*) malloc ( shell_num * sizeof(int32_t));
+rc = qmckl_get_ao_basis_shell_ang_mom (context, shell_ang_mom_test, shell_num);
+assert (rc == QMCKL_SUCCESS);
+
 for (int64_t i=0 ; i < shell_num ; ++i) {
   assert(shell_ang_mom_test[i] == shell_ang_mom[i]);
  }
 
-shell_factor_test = qmckl_get_ao_basis_shell_factor  (context);
+shell_factor_test = (double*) malloc ( shell_num * sizeof(double));
+rc = qmckl_get_ao_basis_shell_factor  (context, shell_factor_test, shell_num);
+assert (rc == QMCKL_SUCCESS);
+
 for (int64_t i=0 ; i < shell_num ; ++i) {
   assert(shell_factor_test[i] == shell_factor[i]);
 }
 
-shell_prim_num_test = qmckl_get_ao_basis_shell_prim_num (context);
+shell_prim_num_test = (int64_t*) malloc ( shell_num * sizeof(int64_t));
+rc = qmckl_get_ao_basis_shell_prim_num (context, shell_prim_num_test, shell_num);
+assert (rc == QMCKL_SUCCESS);
+
 for (int64_t i=0 ; i < shell_num ; ++i) {
   assert(shell_prim_num_test[i] == shell_prim_num[i]);
 }
 
-shell_prim_index_test = qmckl_get_ao_basis_shell_prim_index (context);
+shell_prim_index_test = (int64_t*) malloc ( shell_num * sizeof(int64_t));
+rc = qmckl_get_ao_basis_shell_prim_index (context, shell_prim_index_test, shell_num);
+assert (rc == QMCKL_SUCCESS);
+
 for (int64_t i=0 ; i < shell_num ; ++i) {
   assert(shell_prim_index_test[i] == shell_prim_index[i]);
 }
 
-exponent_test = qmckl_get_ao_basis_exponent(context);
+exponent_test = (double*) malloc ( prim_num * sizeof(double));
+rc = qmckl_get_ao_basis_exponent(context, exponent_test, prim_num);
+assert (rc == QMCKL_SUCCESS);
+
 for (int64_t i=0 ; i < prim_num ; ++i) {
   assert(exponent_test[i] == exponent[i]);
 }
 
-coefficient_test = qmckl_get_ao_basis_coefficient(context);
+coefficient_test = (double*) malloc ( prim_num * sizeof(double));
+rc = qmckl_get_ao_basis_coefficient(context, coefficient_test, prim_num);
+assert (rc == QMCKL_SUCCESS);
+
 for (int64_t i=0 ; i < prim_num ; ++i) {
   assert(coefficient_test[i] == coefficient[i]);
 }
 
-prim_factor_test = qmckl_get_ao_basis_prim_factor (context);
+prim_factor_test = (double*) malloc ( prim_num * sizeof(double));
+rc = qmckl_get_ao_basis_prim_factor (context, prim_factor_test, prim_num);
+assert (rc == QMCKL_SUCCESS);
+
 for (int64_t i=0 ; i < prim_num ; ++i) {
   assert(prim_factor_test[i] == prim_factor[i]);
 }
 
-ao_num_test = qmckl_get_ao_basis_ao_num(context);
+rc = qmckl_get_ao_basis_ao_num(context, &ao_num_test);
 assert(ao_num == ao_num_test);
 
-ao_factor_test = qmckl_get_ao_basis_ao_factor (context); 
+ao_factor_test = (double*) malloc ( ao_num * sizeof(double));
+rc = qmckl_get_ao_basis_ao_factor (context, ao_factor_test, ao_num); 
+assert (rc == QMCKL_SUCCESS);
+
 for (int64_t i=0 ; i < ao_num ; ++i) {
   assert(ao_factor_test[i] == ao_factor[i]);
 }