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58 KiB
58 KiB
Forces
- Introduction
- Context
- Finite-difference function
- Force of en jastrow value
- Force of en jastrow gradient
- Force of en jastrow laplacien
Introduction
Context
Data structure
typedef struct qmckl_forces_struct{
double * restrict forces_jastrow_en;
uint64_t forces_jastrow_en_date;
double * restrict forces_jastrow_en_g;
uint64_t forces_jastrow_en_g_date;
double * restrict forces_jastrow_en_l;
uint64_t forces_jastrow_en_l_date;
} qmckl_forces_struct;
Test
/* Reference input data */
int64_t walk_num = n2_walk_num;
int64_t elec_num = n2_elec_num;
int64_t elec_up_num = n2_elec_up_num;
int64_t elec_dn_num = n2_elec_dn_num;
int64_t nucl_num = n2_nucl_num;
double rescale_factor_ee = 0.6;
double rescale_factor_en[2] = { 0.6, 0.6 };
double* elec_coord = &(n2_elec_coord[0][0][0]);
const double* nucl_charge = n2_charge;
double* nucl_coord = &(n2_nucl_coord[0][0]);
/* Provide Electron data */
qmckl_exit_code rc;
assert(!qmckl_electron_provided(context));
rc = qmckl_check(context,
qmckl_set_electron_num (context, elec_up_num, elec_dn_num)
);
assert(rc == QMCKL_SUCCESS);
assert(qmckl_electron_provided(context));
rc = qmckl_check(context,
qmckl_set_electron_coord (context, 'N', walk_num, elec_coord, walk_num*3*elec_num)
);
assert(rc == QMCKL_SUCCESS);
double elec_coord2[walk_num*3*elec_num];
rc = qmckl_check(context,
qmckl_get_electron_coord (context, 'N', elec_coord2, walk_num*3*elec_num)
);
assert(rc == QMCKL_SUCCESS);
for (int64_t i=0 ; i<3*elec_num ; ++i) {
assert( elec_coord[i] == elec_coord2[i] );
}
/* Provide Nucleus data */
assert(!qmckl_nucleus_provided(context));
rc = qmckl_check(context,
qmckl_set_nucleus_num (context, nucl_num)
);
assert(rc == QMCKL_SUCCESS);
assert(!qmckl_nucleus_provided(context));
double nucl_coord2[3*nucl_num];
rc = qmckl_get_nucleus_coord (context, 'T', nucl_coord2, 3*nucl_num);
assert(rc == QMCKL_NOT_PROVIDED);
rc = qmckl_check(context,
qmckl_set_nucleus_coord (context, 'T', &(nucl_coord[0]), 3*nucl_num)
);
assert(rc == QMCKL_SUCCESS);
assert(!qmckl_nucleus_provided(context));
rc = qmckl_check(context,
qmckl_get_nucleus_coord (context, 'N', nucl_coord2, nucl_num*3)
);
assert(rc == QMCKL_SUCCESS);
for (int64_t k=0 ; k<3 ; ++k) {
for (int64_t i=0 ; i<nucl_num ; ++i) {
assert( nucl_coord[nucl_num*k+i] == nucl_coord2[3*i+k] );
}
}
rc = qmckl_check(context,
qmckl_get_nucleus_coord (context, 'T', nucl_coord2, nucl_num*3)
);
assert(rc == QMCKL_SUCCESS);
for (int64_t i=0 ; i<3*nucl_num ; ++i) {
assert( nucl_coord[i] == nucl_coord2[i] );
}
double nucl_charge2[nucl_num];
rc = qmckl_get_nucleus_charge(context, nucl_charge2, nucl_num);
assert(rc == QMCKL_NOT_PROVIDED);
rc = qmckl_check(context,
qmckl_set_nucleus_charge(context, nucl_charge, nucl_num)
);
assert(rc == QMCKL_SUCCESS);
rc = qmckl_check(context,
qmckl_get_nucleus_charge(context, nucl_charge2, nucl_num)
);
assert(rc == QMCKL_SUCCESS);
for (int64_t i=0 ; i<nucl_num ; ++i) {
assert( nucl_charge[i] == nucl_charge2[i] );
}
assert(qmckl_nucleus_provided(context));
assert(qmckl_electron_provided(context));
int64_t type_nucl_num = n2_type_nucl_num;
int64_t* type_nucl_vector = &(n2_type_nucl_vector[0]);
int64_t aord_num = n2_aord_num;
int64_t bord_num = n2_bord_num;
int64_t cord_num = n2_cord_num;
double* a_vector = &(n2_a_vector[0][0]);
double* b_vector = &(n2_b_vector[0]);
double* c_vector = &(n2_c_vector[0][0]);
int64_t dim_c_vector=0;
assert(!qmckl_jastrow_champ_provided(context));
/* Set the data */
rc = qmckl_check(context,
qmckl_set_jastrow_champ_spin_independent(context, 0)
);
rc = qmckl_check(context,
qmckl_set_jastrow_champ_aord_num(context, aord_num)
);
rc = qmckl_check(context,
qmckl_set_jastrow_champ_bord_num(context, bord_num)
);
rc = qmckl_check(context,
qmckl_set_jastrow_champ_cord_num(context, cord_num)
);
assert(rc == QMCKL_SUCCESS);
rc = qmckl_check(context,
qmckl_set_jastrow_champ_type_nucl_num(context, type_nucl_num)
);
assert(rc == QMCKL_SUCCESS);
rc = qmckl_check(context,
qmckl_set_jastrow_champ_type_nucl_vector(context, type_nucl_vector, nucl_num)
);
assert(rc == QMCKL_SUCCESS);
rc = qmckl_check(context,
qmckl_set_jastrow_champ_a_vector(context, a_vector,(aord_num+1)*type_nucl_num)
);
assert(rc == QMCKL_SUCCESS);
rc = qmckl_check(context,
qmckl_set_jastrow_champ_b_vector(context, b_vector,(bord_num+1))
);
assert(rc == QMCKL_SUCCESS);
rc = qmckl_check(context,
qmckl_get_jastrow_champ_dim_c_vector(context, &dim_c_vector)
);
assert(rc == QMCKL_SUCCESS);
rc = qmckl_check(context,
qmckl_set_jastrow_champ_c_vector(context, c_vector, dim_c_vector*type_nucl_num)
);
assert(rc == QMCKL_SUCCESS);
double k_ee = 0.;
double k_en[2] = { 0., 0. };
rc = qmckl_check(context,
qmckl_set_jastrow_champ_rescale_factor_en(context, rescale_factor_en, type_nucl_num)
);
assert(rc == QMCKL_SUCCESS);
rc = qmckl_check(context,
qmckl_set_jastrow_champ_rescale_factor_ee(context, rescale_factor_ee)
);
assert(rc == QMCKL_SUCCESS);
rc = qmckl_check(context,
qmckl_get_jastrow_champ_rescale_factor_ee (context, &k_ee)
);
assert(rc == QMCKL_SUCCESS);
assert(k_ee == rescale_factor_ee);
rc = qmckl_check(context,
qmckl_get_jastrow_champ_rescale_factor_en (context, &(k_en[0]), type_nucl_num)
);
assert(rc == QMCKL_SUCCESS);
for (int i=0 ; i<type_nucl_num ; ++i) {
assert(k_en[i] == rescale_factor_en[i]);
}
/* Check if Jastrow is properly initialized */
assert(qmckl_jastrow_champ_provided(context));
double delta_x = 0.00001;
Finite-difference function
We introduce here a general function to compute the derivatives of any quantity with respect to nuclear coordinates. using finite-differences.
Force of en jastrow value
Get
qmckl_exit_code
qmckl_get_forces_jastrow_en(qmckl_context context,
double* const forces_jastrow_en,
const int64_t size_max);
interface
integer(qmckl_exit_code) function qmckl_get_forces_jastrow_en (context, &
forces_jastrow_en, size_max) bind(C)
use, intrinsic :: iso_c_binding
import
implicit none
integer (qmckl_context) , intent(in), value :: context
integer(c_int64_t), intent(in), value :: size_max
real(c_double), intent(out) :: forces_jastrow_en(size_max)
end function qmckl_get_forces_jastrow_en
end interface
Compute
Variable | Type | In/Out | Description |
---|---|---|---|
context |
qmckl_context |
in | Global state |
walk_num |
int64_t |
in | Number of walkers |
elec_num |
int64_t |
in | Number of electrons |
nucl_num |
int64_t |
in | Number of nuclei |
type_nucl_num |
int64_t |
in | Number of unique nuclei |
type_nucl_vector |
int64_t[nucl_num] |
in | IDs of unique nuclei |
aord_num |
int64_t |
in | Number of coefficients |
a_vector |
double[type_nucl_num][aord_num+1] |
in | List of coefficients |
en_distance_rescaled |
double[walk_num][nucl_num][elec_num] |
in | Electron-nucleus distances |
en_distance_rescaled_gl |
double[walk_num][nucl_num][elec_num][4] |
in | Electron-nucleus distance derivatives |
forces_jastrow_en |
double[walk_num][nucl_num][3] |
out | Electron-nucleus forces |
function qmckl_compute_forces_jastrow_en_doc( &
context, walk_num, elec_num, nucl_num, type_nucl_num, &
type_nucl_vector, aord_num, a_vector, &
en_distance_rescaled, en_distance_rescaled_gl, forces_jastrow_en) &
bind(C) result(info)
use qmckl
implicit none
integer (qmckl_context), intent(in), value :: context
integer (c_int64_t) , intent(in) , value :: walk_num
integer (c_int64_t) , intent(in) , value :: elec_num
integer (c_int64_t) , intent(in) , value :: nucl_num
integer (c_int64_t) , intent(in) , value :: type_nucl_num
integer (c_int64_t) , intent(in) :: type_nucl_vector(nucl_num)
integer (c_int64_t) , intent(in) , value :: aord_num
real (c_double ) , intent(in) :: a_vector(aord_num+1,type_nucl_num)
real (c_double ) , intent(in) :: en_distance_rescaled(elec_num,nucl_num,walk_num)
real (c_double ) , intent(in) :: en_distance_rescaled_gl(4, elec_num,nucl_num,walk_num)
real (c_double ) , intent(out) :: forces_jastrow_en(3,nucl_num,walk_num)
integer(qmckl_exit_code) :: info
integer*8 :: i, a, k, nw, ii
double precision :: x, x1, kf
double precision :: denom, invdenom, invdenom2, f
double precision :: dx(3)
info = QMCKL_SUCCESS
if (context == QMCKL_NULL_CONTEXT) then
info = QMCKL_INVALID_CONTEXT
return
endif
if (walk_num <= 0) then
info = QMCKL_INVALID_ARG_2
return
endif
if (elec_num <= 0) then
info = QMCKL_INVALID_ARG_3
return
endif
if (nucl_num <= 0) then
info = QMCKL_INVALID_ARG_4
return
endif
if (aord_num < 0) then
info = QMCKL_INVALID_ARG_7
return
endif
do nw =1, walk_num
forces_jastrow_en(:,:,nw) = 0.0d0
do a = 1, nucl_num
do i = 1, elec_num
x = en_distance_rescaled(i,a,nw)
if(abs(x) < 1.d-12) continue
denom = 1.0d0 + a_vector(2, type_nucl_vector(a)+1) * x
invdenom = 1.0d0 / denom
invdenom2 = invdenom*invdenom
dx(1) = -en_distance_rescaled_gl(1,i,a,nw)
dx(2) = -en_distance_rescaled_gl(2,i,a,nw)
dx(3) = -en_distance_rescaled_gl(3,i,a,nw)
f = a_vector(1, type_nucl_vector(a)+1) * invdenom2
forces_jastrow_en(1,a,nw) = forces_jastrow_en(1,a,nw) + f * dx(1)
forces_jastrow_en(2,a,nw) = forces_jastrow_en(2,a,nw) + f * dx(2)
forces_jastrow_en(3,a,nw) = forces_jastrow_en(3,a,nw) + f * dx(3)
kf = 2.d0
x1 = x
x = 1.d0
do k=2, aord_num
f = a_vector(k+1,type_nucl_vector(a)+1) * kf * x
forces_jastrow_en(1,a,nw) = forces_jastrow_en(1,a,nw) + f * x1 * dx(1)
forces_jastrow_en(2,a,nw) = forces_jastrow_en(2,a,nw) + f * x1 * dx(2)
forces_jastrow_en(3,a,nw) = forces_jastrow_en(3,a,nw) + f * x1 * dx(3)
x = x*x1
kf = kf + 1.d0
end do
end do
end do
end do
end function qmckl_compute_forces_jastrow_en_doc
Test
printf("Forces Jastrow en\n");
/* Check if Jastrow is properly initialized */
assert(qmckl_jastrow_champ_provided(context));
rc = qmckl_set_nucleus_coord(context, 'T', &(nucl_coord[0]), 3*nucl_num);
assert(rc == QMCKL_SUCCESS);
double forces_jastrow_en[walk_num][nucl_num][3];
rc = qmckl_get_forces_jastrow_en(context, &forces_jastrow_en[0][0][0], 3*nucl_num*walk_num);
assert(rc == QMCKL_SUCCESS);
double finite_difference_force_en[walk_num][nucl_num][3];
rc = qmckl_finite_difference_deriv_n(context, delta_x, &qmckl_get_jastrow_champ_factor_en, &(finite_difference_force_en[0][0][0]), 1);
for (int nw = 0; nw < walk_num; nw++){
for (int a = 0; a < nucl_num; a++) {
for (int k = 0; k < 3; k++){
//printf("%.10f\t", finite_difference_force_en[nw][a][k]);
//printf("%.10f\n", forces_jastrow_en[nw][a][k]);
}
}
}
for (int nw = 0; nw < walk_num; nw++){
for (int a = 0; a < nucl_num; a++) {
for (int k = 0; k < 3; k++){
assert(fabs(finite_difference_force_en[nw][a][k] - forces_jastrow_en[nw][a][k]) < 1.e-8);
}
}
}
printf("OK\n");
Force of en jastrow gradient
Get
qmckl_exit_code
qmckl_get_forces_jastrow_en_g(qmckl_context context,
double* const forces_jastrow_en_g,
const int64_t size_max);
interface
integer(qmckl_exit_code) function qmckl_get_forces_jastrow_en_g (context, &
forces_jastrow_en_g, size_max) bind(C)
use, intrinsic :: iso_c_binding
import
implicit none
integer (qmckl_context) , intent(in), value :: context
integer(c_int64_t), intent(in), value :: size_max
real(c_double), intent(out) :: forces_jastrow_en_g(size_max)
end function qmckl_get_forces_jastrow_en_g
end interface
Compute
Variable | Type | In/Out | Description |
---|---|---|---|
context |
qmckl_context |
in | Global state |
walk_num |
int64_t |
in | Number of walkers |
elec_num |
int64_t |
in | Number of electrons |
nucl_num |
int64_t |
in | Number of nuclei |
type_nucl_num |
int64_t |
in | Number of unique nuclei |
type_nucl_vector |
int64_t[nucl_num] |
in | IDs of unique nuclei |
aord_num |
int64_t |
in | Number of coefficients |
a_vector |
double[type_nucl_num][aord_num+1] |
in | List of coefficients |
rescale_factor_en |
double[type_nucl_num] |
in | Rescale factor for electron-nucleus |
en_distance |
double[elec_num][nucl_num] |
in | Electron-nucleus distances |
en_distance_rescaled |
double[walk_num][nucl_num][elec_num] |
in | Electron-nucleus distances |
en_distance_rescaled_gl |
double[walk_num][nucl_num][elec_num][4] |
in | Electron-nucleus distance derivatives |
forces_jastrow_en_g |
double[walk_num][nucl_num][3][elec_num][3] |
out | Electron-nucleus forces |
function qmckl_compute_forces_jastrow_en_g_doc( &
context, walk_num, elec_num, nucl_num, type_nucl_num, &
type_nucl_vector, aord_num, a_vector, rescale_factor_en, en_distance, &
en_distance_rescaled, en_distance_rescaled_gl, forces_jastrow_en_g) &
bind(C) result(info)
use qmckl
implicit none
integer (qmckl_context), intent(in), value :: context
integer (c_int64_t) , intent(in) , value :: walk_num
integer (c_int64_t) , intent(in) , value :: elec_num
integer (c_int64_t) , intent(in) , value :: nucl_num
integer (c_int64_t) , intent(in) , value :: type_nucl_num
integer (c_int64_t) , intent(in) :: type_nucl_vector(nucl_num)
integer (c_int64_t) , intent(in) , value :: aord_num
real (c_double ) , intent(in) :: a_vector(aord_num+1,type_nucl_num)
real (c_double ) , intent(in) :: rescale_factor_en(type_nucl_num)
real (c_double ) , intent(in) :: en_distance(nucl_num, elec_num)
real (c_double ) , intent(in) :: en_distance_rescaled(elec_num,nucl_num,walk_num)
real (c_double ) , intent(in) :: en_distance_rescaled_gl(4, elec_num,nucl_num,walk_num)
real (c_double ) , intent(out) :: forces_jastrow_en_g(3,elec_num,3,nucl_num,walk_num)
integer(qmckl_exit_code) :: info
integer*8 :: i, a, k, nw, ii, m,l
double precision :: x, x1, kf
double precision :: denom, invdenom, invdenom2, f, f2, expk, invdist
double precision :: dx(4)
info = QMCKL_SUCCESS
if (context == QMCKL_NULL_CONTEXT) then
info = QMCKL_INVALID_CONTEXT
return
endif
if (walk_num <= 0) then
info = QMCKL_INVALID_ARG_2
return
endif
if (elec_num <= 0) then
info = QMCKL_INVALID_ARG_3
return
endif
if (nucl_num <= 0) then
info = QMCKL_INVALID_ARG_4
return
endif
if (aord_num < 0) then
info = QMCKL_INVALID_ARG_7
return
endif
do nw =1, walk_num
forces_jastrow_en_g(:,:,:,:,nw) = 0.0d0
do a = 1, nucl_num
do i = 1, elec_num
expk = dexp(rescale_factor_en(type_nucl_vector(a)+1) * en_distance(a,i))
invdist = 1.d0 / en_distance(a,i)
x = en_distance_rescaled(i,a,nw)
if(abs(x) < 1.d-12) continue
denom = 1.0d0 + a_vector(2, type_nucl_vector(a)+1) * x
invdenom = 1.0d0 / denom
invdenom2 = invdenom*invdenom
f = a_vector(1, type_nucl_vector(a)+1) * invdenom2
do m = 1, 3
dx(m) = en_distance_rescaled_gl(m,i,a,nw)
end do
do m = 1, 3
do l = 1,3
if (m == l) then
forces_jastrow_en_g(m,i,l,a,nw) = forces_jastrow_en_g(m,i,l,a,nw) - f * invdist / expk
end if
forces_jastrow_en_g(m,i,l,a,nw) = forces_jastrow_en_g(m,i,l,a,nw) + f * dx(m) * dx(l) * invdist * expk
forces_jastrow_en_g(m,i,l,a,nw) = forces_jastrow_en_g(m,i,l,a,nw) + 2.d0 * f * invdenom * &
a_vector(2, type_nucl_vector(a)+1) * dx(m) * dx(l)
end do
end do
kf = 2.d0
x1 = x
x = 1.d0
do k=2, aord_num
f = a_vector(k+1,type_nucl_vector(a)+1) * kf * x
f2 = a_vector(k+1,type_nucl_vector(a)+1) * kf * x * (kf-1.d0)
do m = 1, 3
do l = 1, 3
if (m == l) then
forces_jastrow_en_g(m,i,l,a,nw) = forces_jastrow_en_g(m,i,l,a,nw) - f * x1 * invdist / expk
end if
forces_jastrow_en_g(m,i,l,a,nw) = forces_jastrow_en_g(m,i,l,a,nw) - f2 * dx(m) * dx(l) &
+ f * x1 * dx(m) * dx(l) * rescale_factor_en(type_nucl_vector(a)+1) * expk &
+ f * x1 * dx(m) * dx(l) * invdist * expk
end do
end do
x = x*x1
kf = kf + 1.d0
end do
end do
end do
end do
end function qmckl_compute_forces_jastrow_en_g_doc
Test
printf("Forces Jastrow en G\n");
/* Check if Jastrow is properly initialized */
assert(qmckl_jastrow_champ_provided(context));
rc = qmckl_set_nucleus_coord(context, 'T', &(nucl_coord[0]), 3*nucl_num);
assert(rc == QMCKL_SUCCESS);
double forces_jastrow_en_g[walk_num][nucl_num][3][elec_num][3];
rc = qmckl_get_forces_jastrow_en_g(context, &forces_jastrow_en_g[0][0][0][0][0], 3*3*nucl_num*walk_num*elec_num);
assert(rc == QMCKL_SUCCESS);
double finite_difference_force_en_g[walk_num][nucl_num][3][4][elec_num];
rc = qmckl_finite_difference_deriv_n(context, delta_x, &qmckl_get_jastrow_champ_factor_en_gl, &finite_difference_force_en_g[0][0][0][0][0], 4*elec_num);
for (int nw = 0; nw < walk_num; nw++){
for (int a = 0; a < nucl_num; a++) {
for (int k = 0; k < 3; k++){
for (int i = 0; i < elec_num; i++){
for (int l = 1; l < 3; l++){
//printf("finite_difference_force_en_g[%i][%i][%i][%i][%i] %+3.10f \n", nw,a,k,l,i,finite_difference_force_en_g[nw][a][k][l][i]);
//printf("forces_jastrow_en_g [%i][%i][%i][%i][%i] %+3.10f\n", nw,a,k,i,l,forces_jastrow_en_g[nw][a][k][i][l]);
}
}
}
}
}
for (int nw = 0; nw < walk_num; nw++){
for (int a = 0; a < nucl_num; a++) {
for (int k = 0; k < 3; k++){
for (int i = 0; i < elec_num; i++){
for (int l = 1; l < 3; l++){
assert(fabs(finite_difference_force_en_g[nw][a][k][l][i] - forces_jastrow_en_g[nw][a][k][i][l]) < 1.e-8);
}
}
}
}
}
printf("OK\n");
Force of en jastrow laplacien
Get
qmckl_exit_code
qmckl_get_forces_jastrow_en_l(qmckl_context context,
double* const forces_jastrow_en_l,
const int64_t size_max);
interface
integer(qmckl_exit_code) function qmckl_get_forces_jastrow_en_l (context, &
forces_jastrow_en_l, size_max) bind(C)
use, intrinsic :: iso_c_binding
import
implicit none
integer (qmckl_context) , intent(in), value :: context
integer(c_int64_t), intent(in), value :: size_max
real(c_double), intent(out) :: forces_jastrow_en_l(size_max)
end function qmckl_get_forces_jastrow_en_l
end interface
Compute
Variable | Type | In/Out | Description |
---|---|---|---|
context |
qmckl_context |
in | Global state |
walk_num |
int64_t |
in | Number of walkers |
elec_num |
int64_t |
in | Number of electrons |
nucl_num |
int64_t |
in | Number of nuclei |
type_nucl_num |
int64_t |
in | Number of unique nuclei |
type_nucl_vector |
int64_t[nucl_num] |
in | IDs of unique nuclei |
aord_num |
int64_t |
in | Number of coefficients |
a_vector |
double[type_nucl_num][aord_num+1] |
in | List of coefficients |
rescale_factor_en |
double[type_nucl_num] |
in | Rescale factor for electron-nucleus |
en_distance |
double[elec_num][nucl_num] |
in | Electron-nucleus distances |
en_distance_rescaled |
double[walk_num][nucl_num][elec_num] |
in | Electron-nucleus distances |
en_distance_rescaled_gl |
double[walk_num][nucl_num][elec_num][4] |
in | Electron-nucleus distance derivatives |
forces_jastrow_en_l |
double[walk_num][nucl_num][3] |
out | Electron-nucleus forces |
function qmckl_compute_forces_jastrow_en_l_doc( &
context, walk_num, elec_num, nucl_num, type_nucl_num, &
type_nucl_vector, aord_num, a_vector, rescale_factor_en, en_distance, &
en_distance_rescaled, en_distance_rescaled_gl, forces_jastrow_en_l) &
bind(C) result(info)
use qmckl
implicit none
integer (qmckl_context), intent(in), value :: context
integer (c_int64_t) , intent(in) , value :: walk_num
integer (c_int64_t) , intent(in) , value :: elec_num
integer (c_int64_t) , intent(in) , value :: nucl_num
integer (c_int64_t) , intent(in) , value :: type_nucl_num
integer (c_int64_t) , intent(in) :: type_nucl_vector(nucl_num)
integer (c_int64_t) , intent(in) , value :: aord_num
real (c_double ) , intent(in) :: a_vector(aord_num+1,type_nucl_num)
real (c_double ) , intent(in) :: rescale_factor_en(type_nucl_num)
real (c_double ) , intent(in) :: en_distance(nucl_num, elec_num)
real (c_double ) , intent(in) :: en_distance_rescaled(elec_num,nucl_num,walk_num)
real (c_double ) , intent(in) :: en_distance_rescaled_gl(4, elec_num,nucl_num,walk_num)
real (c_double ) , intent(out) :: forces_jastrow_en_l(3,nucl_num,walk_num)
integer(qmckl_exit_code) :: info
integer*8 :: i, a, k, nw, ii, m,l
double precision :: x, x1, kf
double precision :: denom, invdenom, invdenom2, f, f2, expk, invdist
double precision :: dx(4)
info = QMCKL_SUCCESS
if (context == QMCKL_NULL_CONTEXT) then
info = QMCKL_INVALID_CONTEXT
return
endif
if (walk_num <= 0) then
info = QMCKL_INVALID_ARG_2
return
endif
if (elec_num <= 0) then
info = QMCKL_INVALID_ARG_3
return
endif
if (nucl_num <= 0) then
info = QMCKL_INVALID_ARG_4
return
endif
if (aord_num < 0) then
info = QMCKL_INVALID_ARG_7
return
endif
do nw =1, walk_num
forces_jastrow_en_l(:,:,nw) = 0.0d0
do a = 1, nucl_num
do i = 1, elec_num
expk = dexp(rescale_factor_en(type_nucl_vector(a)+1) * en_distance(a,i))
invdist = 1.d0 / en_distance(a,i)
x = en_distance_rescaled(i,a,nw)
if(abs(x) < 1.d-12) continue
denom = 1.0d0 + a_vector(2, type_nucl_vector(a)+1) * x
invdenom = 1.0d0 / denom
invdenom2 = invdenom*invdenom
f = a_vector(1, type_nucl_vector(a)+1) * invdenom2
do m = 1, 4
dx(m) = en_distance_rescaled_gl(m,i,a,nw)
end do
!do m = 1, 3
! do l = 1,3
! if (m == l) then
! forces_jastrow_en_g(l,a,nw) = forces_jastrow_en_g(l,a,nw) - f * invdist / expk
! end if
! forces_jastrow_en_g(l,a,nw) = forces_jastrow_en_g(l,a,nw) + f * dx(m) * dx(l) * invdist * expk
! forces_jastrow_en_g(l,a,nw) = forces_jastrow_en_g(l,a,nw) + 2.d0 * f * invdenom * &
! a_vector(2, type_nucl_vector(a)+1) * dx(m) * dx(l)
! end do
!end do
kf = 2.d0
x1 = x
x = 1.d0
do k=2, aord_num
f = a_vector(k+1,type_nucl_vector(a)+1) * kf * x
do m = 1, 3
forces_jastrow_en_l(m,a,nw) = forces_jastrow_en_l(m,a,nw) &
- f * dx(m) * dx(4) * (kf-1.d0) &
- f / x1 * (kf-1.d0) * (kf-2.d0) * dx(m) /expk /expk &
+ f * x1 * rescale_factor_en(type_nucl_vector(a)+1) * dx(m) * dx(4) * expk &
+ f * x1 * 2 * dx(m) * invdist * invdist &
+ 2 * f * (kf-1.d0) * dx(m) * rescale_factor_en(type_nucl_vector(a)+1) / expk
end do
x = x*x1
kf = kf + 1.d0
end do
end do
end do
end do
end function qmckl_compute_forces_jastrow_en_l_doc
Test
printf("Forces Jastrow en L\n");
/* Check if Jastrow is properly initialized */
assert(qmckl_jastrow_champ_provided(context));
rc = qmckl_set_nucleus_coord(context, 'T', &(nucl_coord[0]), 3*nucl_num);
assert(rc == QMCKL_SUCCESS);
double forces_jastrow_en_l[walk_num][nucl_num][3];
rc = qmckl_get_forces_jastrow_en_l(context, &forces_jastrow_en_l[0][0][0], 3*nucl_num*walk_num);
assert(rc == QMCKL_SUCCESS);
double finite_difference_force_en_l[walk_num][nucl_num][3][4][elec_num];
rc = qmckl_finite_difference_deriv_n(context, delta_x, &qmckl_get_jastrow_champ_factor_en_gl, &finite_difference_force_en_l[0][0][0][0][0], 4*elec_num);
double finite_difference_force_en_l_sum[walk_num][nucl_num][3];
for (int nw = 0; nw < walk_num; nw++){
for (int a = 0; a < nucl_num; a++) {
for (int k = 0; k < 3; k++){
finite_difference_force_en_l_sum[nw][a][k] = 0;
for (int i = 0; i < elec_num; i++){
finite_difference_force_en_l_sum[nw][a][k] = finite_difference_force_en_l_sum[nw][a][k] + finite_difference_force_en_l[nw][a][k][3][i];
}
}
}
}
for (int nw = 0; nw < walk_num; nw++){
for (int a = 0; a < nucl_num; a++) {
for (int k = 0; k < 3; k++){
//printf("finite_difference_force_en_l_sum[%i][%i][%i] %+3.10f \n", nw,a,k,finite_difference_force_en_l_sum[nw][a][k]);
//printf("forces_jastrow_en_l [%i][%i][%i] %+3.10f\n", nw,a,k,forces_jastrow_en_l[nw][a][k]);
}
}
}
for (int nw = 0; nw < walk_num; nw++){
for (int a = 0; a < nucl_num; a++) {
for (int k = 0; k < 3; k++){
assert(fabs(finite_difference_force_en_l_sum[nw][a][k] - forces_jastrow_en_l[nw][a][k]) < 1.e-8);
}
}
}
printf("OK\n");