/**
* @brief Function to set all vmg parameters with a single call
*
* @param handle FCS-object that contains the parameters
* @param max_level The maximum level of the algorithm, i.e. n_gridpoints = 2^max_level.
* @param spline_degree The degree of the interpolating B-Splines.
* @param max_iterations The maximum number of multigrid iterations.
* @param smoothing_steps Number of pre/postsmoothing steps on each level.
* @param cycle_type Cycle-number.
* @param precision Desired precision.
* @param near_field_cells Number of near field cells.
* @param interpolation_order Interpolation order.
* @param discretization_order Discretization order.
*
* @return FCSResult-object containing the return value.
*/
extern FCSResult fcs_vmg_setup(FCS handle, fcs_int max_level,
fcs_int max_iterations, fcs_int smoothing_steps,
fcs_int cycle_type, fcs_float precision, fcs_int near_field_cells,
fcs_int interpolation_order, fcs_int discretization_order)
{
FCSResult result;
char fnc_name[] = "fcs_vmg_setup";
if (handle == NULL)
return fcsResult_create(FCS_NULL_ARGUMENT, fnc_name, "null pointer supplied as handle");
if (fcs_get_method(handle) != FCS_VMG)
return fcsResult_create(FCS_WRONG_ARGUMENT, fnc_name, "Wrong method chosen. You should choose \"vmg\".");
result = fcs_vmg_set_max_level(handle, max_level);
if (result != NULL)
return result;
result = fcs_vmg_set_max_iterations(handle, max_iterations);
if (result != NULL)
return result;
result = fcs_vmg_set_smoothing_steps(handle, smoothing_steps);
if (result != NULL)
return result;
result = fcs_vmg_set_cycle_type(handle, cycle_type);
if (result != NULL)
return result;
result = fcs_vmg_set_precision(handle, precision);
if (result != NULL)
return result;
result = fcs_vmg_set_near_field_cells(handle, near_field_cells);
if (result != NULL)
return result;
result = fcs_vmg_set_interpolation_order(handle, interpolation_order);
if (result != NULL)
return result;
result = fcs_vmg_set_discretization_order(handle, discretization_order);
if (result != NULL)
return result;
return NULL;
}
void init_fcs(void) {
FCSResult res;
fcs_int srf = 1;
char *method;
fcs_int pbc [3] = { pbc_dirs.x, pbc_dirs.y, pbc_dirs.z };
fcs_float BoxX[3] = { box_x.x, box_x.y, box_x.z };
fcs_float BoxY[3] = { box_y.x, box_y.y, box_y.z };
fcs_float BoxZ[3] = { box_z.x, box_z.y, box_z.z };
fcs_float off [3] = { 0.0, 0.0, 0.0 };
/* subtract CM momentum */
if (0 == imdrestart) {
int i, k; real ptot[4], ptot_2[4], px, py, pz;
ptot[0] = 0.0; ptot[1] = 0.0; ptot[2] = 0.0, ptot[3] = 0.0;
for (k=0; k<NCELLS; ++k) { /* loop over all cells */
cell *p = CELLPTR(k);
for (i=0; i<p->n; i++) {
ptot[0] += IMPULS(p,i,X);
ptot[1] += IMPULS(p,i,Y);
ptot[2] += IMPULS(p,i,Z);
ptot[3] += MASSE(p,i);
}
}
#ifdef MPI
MPI_Allreduce( ptot, ptot_2, 4, REAL, MPI_SUM, cpugrid);
ptot[0] = ptot_2[0];
ptot[1] = ptot_2[1];
ptot[2] = ptot_2[2];
ptot[3] = ptot_2[3];
#endif
px = ptot[0]/ptot[3];
py = ptot[1]/ptot[3];
pz = ptot[2]/ptot[3];
for (k=0; k<NCELLS; ++k) { /* loop over all cells */
cell *p = CELLPTR(k);
for (i=0; i<p->n; i++) {
IMPULS(p,i,X) -= px * MASSE(p,i);
IMPULS(p,i,Y) -= py * MASSE(p,i);
IMPULS(p,i,Z) -= pz * MASSE(p,i);
}
}
}
switch (fcs_method) {
case FCS_METH_DIRECT: method = "direct"; break;
case FCS_METH_PEPC: method = "pepc"; break;
case FCS_METH_FMM: method = "fmm"; break;
case FCS_METH_P3M: method = "p3m"; srf = fcs_near_field_flag; break;
case FCS_METH_P2NFFT: method = "p2nfft"; srf = fcs_near_field_flag; break;
case FCS_METH_VMG: method = "vmg"; break;
case FCS_METH_PP3MG: method = "pp3mg"; break;
}
/* initialize handle and set common parameters */
res = fcs_init(&handle, method, cpugrid);
ASSERT_FCS(res);
res = fcs_set_common(handle, srf, BoxX, BoxY, BoxZ, off, pbc, natoms);
ASSERT_FCS(res);
res = fcs_require_virial(handle, 1);
ASSERT_FCS(res);
/* set method specific parameters */
switch (fcs_method) {
#ifdef FCS_ENABLE_DIRECT
case FCS_METH_DIRECT:
/* nothing to do */
break;
#endif
#ifdef FCS_ENABLE_PEPC
case FCS_METH_PEPC:
res = fcs_pepc_setup(handle, (fcs_float)fcs_pepc_eps,
(fcs_float)fcs_pepc_theta );
ASSERT_FCS(res);
res = fcs_pepc_set_num_walk_threads( handle, (fcs_int)fcs_pepc_nthreads );
ASSERT_FCS(res);
break;
#endif
#ifdef FCS_ENABLE_FMM
case FCS_METH_FMM:
res = fcs_fmm_set_absrel(handle, (fcs_int)fcs_fmm_absrel);
ASSERT_FCS(res);
res = fcs_fmm_set_tolerance_energy(handle, (fcs_float)fcs_tolerance);
ASSERT_FCS(res);
break;
#endif
#ifdef FCS_ENABLE_P3M
case FCS_METH_P3M:
if (0==srf) {
res = fcs_p3m_set_r_cut(handle, (fcs_float)fcs_rcut);
ASSERT_FCS(res);
}
res = fcs_set_tolerance(handle, FCS_TOLERANCE_TYPE_FIELD,
(fcs_float)fcs_tolerance);
ASSERT_FCS(res);
if (fcs_grid_dim.x)
res = fcs_p3m_set_grid(handle, (fcs_int)fcs_grid_dim.x);
ASSERT_FCS(res);
break;
#endif
#ifdef FCS_ENABLE_P2NFFT
case FCS_METH_P2NFFT:
if (0==srf) {
res = fcs_p2nfft_set_r_cut(handle, (fcs_float)fcs_rcut);
ASSERT_FCS(res);
}
res = fcs_set_tolerance(handle, FCS_TOLERANCE_TYPE_FIELD,
(fcs_float)fcs_tolerance);
ASSERT_FCS(res);
if (fcs_grid_dim.x) {
res = fcs_p2nfft_set_grid(handle, (fcs_int)fcs_grid_dim.x,
(fcs_int)fcs_grid_dim.y, (fcs_int)fcs_grid_dim.z);
ASSERT_FCS(res);
}
if (fcs_p2nfft_intpol_order) {
res = fcs_p2nfft_set_pnfft_interpolation_order(handle,
(fcs_int)fcs_p2nfft_intpol_order);
ASSERT_FCS(res);
}
if (fcs_p2nfft_epsI) {
res = fcs_p2nfft_set_epsI(handle, (fcs_float)fcs_p2nfft_epsI);
ASSERT_FCS(res);
}
//res = fcs_p2nfft_set_pnfft_window_by_name(handle, "bspline");
//ASSERT_FCS(res);
break;
#endif
#ifdef FCS_ENABLE_VMG
case FCS_METH_VMG:
if (fcs_vmg_near_field_cells) {
res = fcs_vmg_set_near_field_cells(handle, (fcs_int)fcs_vmg_near_field_cells);
ASSERT_FCS(res);
}
if (fcs_vmg_interpol_order) {
res = fcs_vmg_set_interpolation_order(handle, (fcs_int)fcs_vmg_interpol_order);
ASSERT_FCS(res);
}
if (fcs_vmg_discr_order) {
res = fcs_vmg_set_discretization_order(handle, (fcs_int)fcs_vmg_discr_order);
ASSERT_FCS(res);
}
if (fcs_iter_tolerance > 0) {
res = fcs_vmg_set_precision(handle, (fcs_float)fcs_iter_tolerance);
ASSERT_FCS(res);
}
break;
#endif
#ifdef FCS_ENABLE_PP3MG
case FCS_METH_PP3MG:
/* use default values, if not specified otherwise */
if (fcs_grid_dim.x) {
res = fcs_pp3mg_set_cells_x(handle, (fcs_int)fcs_grid_dim.x);
ASSERT_FCS(res);
res = fcs_pp3mg_set_cells_y(handle, (fcs_int)fcs_grid_dim.y);
ASSERT_FCS(res);
res = fcs_pp3mg_set_cells_z(handle, (fcs_int)fcs_grid_dim.z);
ASSERT_FCS(res);
}
if (fcs_pp3mg_ghosts) {
res = fcs_pp3mg_set_ghosts(handle, (fcs_int)fcs_pp3mg_ghosts);
ASSERT_FCS(res);
}
if (fcs_pp3mg_degree) {
res = fcs_pp3mg_set_degree(handle, (fcs_int)fcs_pp3mg_degree);
ASSERT_FCS(res);
}
if (fcs_pp3mg_max_part) {
res = fcs_pp3mg_set_max_particles(handle, (fcs_int)fcs_pp3mg_max_part);
ASSERT_FCS(res);
}
if (fcs_max_iter) {
res = fcs_pp3mg_set_max_iterations(handle,(fcs_int)fcs_max_iter);
ASSERT_FCS(res);
}
if (fcs_iter_tolerance > 0) {
res = fcs_pp3mg_set_tol(handle, (fcs_float)fcs_iter_tolerance);
ASSERT_FCS(res);
}
break;
#endif
default:
error("FCS method unknown or not implemented");
break;
}
pack_fcs();
res = fcs_tune(handle, nloc, nloc_max, pos, chg);
ASSERT_FCS(res);
/* inform about tuned parameters */
switch (fcs_method) {
fcs_int grid_dim[3];
fcs_float r_cut;
#ifdef FCS_ENABLE_P3M
case FCS_METH_P3M:
res = fcs_p3m_get_r_cut(handle, &r_cut);
ASSERT_FCS(res);
res = fcs_p3m_get_grid(handle, grid_dim);
ASSERT_FCS(res);
if (0==myid)
printf("FCS: Tuned grid dimensions, cutoff: %d %d %d, %f\n",
grid_dim[0], grid_dim[1], grid_dim[2], r_cut);
break;
#endif
#ifdef FCS_ENABLE_P2NFFT
case FCS_METH_P2NFFT:
res = fcs_p2nfft_get_grid(handle, grid_dim, grid_dim+1, grid_dim+2);
ASSERT_FCS(res);
res = fcs_p2nfft_get_r_cut(handle, &r_cut);
ASSERT_FCS(res);
if (0==myid)
printf("FCS: Tuned grid dimensions, cutoff: %d %d %d, %f\n",
grid_dim[0], grid_dim[1], grid_dim[2], r_cut);
break;
#endif
#ifdef FCS_ENABLE_PP3MG
case FCS_METH_PP3MG:
res = fcs_pp3mg_get_cells_x(handle, grid_dim );
ASSERT_FCS(res);
res = fcs_pp3mg_get_cells_y(handle, grid_dim+1);
ASSERT_FCS(res);
res = fcs_pp3mg_get_cells_z(handle, grid_dim+2);
if (0==myid)
printf("FCS: Tuned grid dimensions: %d %d %d\n",
grid_dim[0], grid_dim[1], grid_dim[2]);
ASSERT_FCS(res);
break;
#endif
default:
break;
}
/* add near-field potential, after fcs_tune */
if (0==srf) fcs_update_pottab();
}
/**
* @brief function to set default values if no values are set
* @param handle the FCS-obect into which the default parameters will be entered
* @return FCSResult-object containing the return state
*/
extern FCSResult fcs_vmg_set_default(FCS handle)
{
MPI_Comm comm;
int rank;
const char fnc_name[] = "fcs_vmg_set_default";
comm = fcs_get_communicator(handle);
MPI_Comm_rank(comm, &rank);
if (handle == NULL)
return fcsResult_create(FCS_NULL_ARGUMENT, fnc_name, "null pointer supplied as handle");
if (fcs_get_method(handle) != FCS_VMG)
return fcsResult_create(FCS_WRONG_ARGUMENT, fnc_name, "Wrong method chosen. You should choose \"vmg\".");
fcs_int max_level;
fcs_vmg_get_max_level(handle, &max_level);
if (max_level < 0) {
max_level = 6;
#ifdef FCS_ENABLE_DEBUG
if (rank == 0)
printf("%s: Parameter %s not set. Set default to %d.\n", fnc_name, "max_level", max_level);
#endif
fcs_vmg_set_max_level(handle, max_level);
}
fcs_int max_iter;
fcs_vmg_get_max_iterations(handle, &max_iter);
if (max_iter < 0) {
max_iter = 15;
#ifdef FCS_ENABLE_DEBUG
if (rank == 0)
printf("%s: Parameter %s not set. Set default to %d.\n", fnc_name, "max_iterations", max_iter);
#endif
fcs_vmg_set_max_iterations(handle, max_iter);
}
fcs_int smoothing_steps;
fcs_vmg_get_smoothing_steps(handle, &smoothing_steps);
if (smoothing_steps < 0) {
smoothing_steps = 3;
#ifdef FCS_ENABLE_DEBUG
if (rank == 0)
printf("%s: Parameter %s not set. Set default to %d.\n", fnc_name, "smoothing_steps", smoothing_steps);
#endif
fcs_vmg_set_smoothing_steps(handle, smoothing_steps);
}
fcs_int cycle_type;
fcs_vmg_get_cycle_type(handle, &cycle_type);
if (cycle_type < 0) {
cycle_type = 1;
#ifdef FCS_ENABLE_DEBUG
if (rank == 0)
printf("%s: Parameter %s not set. Set default to %d.\n", fnc_name, "cycle_type", cycle_type);
#endif
fcs_vmg_set_cycle_type(handle, cycle_type);
}
fcs_float precision;
fcs_vmg_get_precision(handle, &precision);
if (precision < 0.0) {
precision = 1.0e-8;
#ifdef FCS_ENABLE_DEBUG
if (rank == 0)
printf("%s: Parameter %s not set. Set default to %e.\n", fnc_name, "precision", precision);
#endif
fcs_vmg_set_precision(handle, precision);
}
fcs_int near_field_cells;
fcs_vmg_get_near_field_cells(handle, &near_field_cells);
if (near_field_cells < 0) {
near_field_cells = 4;
#ifdef FCS_ENABLE_DEBUG
if (rank == 0)
printf("%s: Parameter %s not set. Set default to %d.\n", fnc_name, "near_field_cells", near_field_cells);
#endif
fcs_vmg_set_near_field_cells(handle, near_field_cells);
}
fcs_int interpolation_order;
fcs_vmg_get_interpolation_order(handle, &interpolation_order);
if (interpolation_order < 0) {
interpolation_order = 5;
#ifdef FCS_ENABLE_DEBUG
if (rank == 0)
printf("%s: Parameter %s not set. Set default to %d.\n", fnc_name, "interpolation_order", interpolation_order);
#endif
fcs_vmg_set_interpolation_order(handle, interpolation_order);
}
fcs_int discretization_order;
fcs_vmg_get_discretization_order(handle, &discretization_order);
if (discretization_order < 0) {
discretization_order = 4;
#ifdef FCS_ENABLE_DEBUG
if (rank == 0)
printf("%s: Parameter %s not set. Set default to %d.\n", fnc_name, "discretization_order", discretization_order);
#endif
fcs_vmg_set_discretization_order(handle, discretization_order);
}
return NULL;
}
