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/* ----------------------------------------------------------------------
LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
http://lammps.sandia.gov, Sandia National Laboratories
Steve Plimpton, sjplimp@sandia.gov
Copyright (2003) Sandia Corporation. Under the terms of Contract
DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains
certain rights in this software. This software is distributed under
the GNU General Public License.
See the README file in the top-level LAMMPS directory.
------------------------------------------------------------------------- */
#include "stdlib.h"
#include "string.h"
#include "kspace.h"
#include "atom.h"
#include "comm.h"
#include "force.h"
#include "pair.h"
#include "memory.h"
#include "atom_masks.h"
#include "error.h"
#include "suffix.h"
#include "domain.h"
using namespace LAMMPS_NS;
#define SMALL 0.00001
/* ---------------------------------------------------------------------- */
KSpace::KSpace(LAMMPS *lmp, int narg, char **arg) : Pointers(lmp)
{
energy = 0.0;
virial[0] = virial[1] = virial[2] = virial[3] = virial[4] = virial[5] = 0.0;
triclinic_support = 1;
ewaldflag = pppmflag = msmflag = dispersionflag = tip4pflag = dipoleflag = 0;
compute_flag = 1;
group_group_enable = 0;
stagger_flag = 0;
order = 5;
gridflag = 0;
gewaldflag = 0;
minorder = 2;
overlap_allowed = 1;
fftbench = 0;
// default to using MPI collectives for FFT/remap only on IBM BlueGene
#ifdef __bg__
collective_flag = 1;
#else
collective_flag = 0;
#endif
kewaldflag = 0;
order_6 = 5;
gridflag_6 = 0;
gewaldflag_6 = 0;
slabflag = 0;
differentiation_flag = 0;
slab_volfactor = 1;
suffix_flag = Suffix::NONE;
adjust_cutoff_flag = 1;
scalar_pressure_flag = 0;
accuracy_absolute = -1.0;
accuracy_real_6 = -1.0;
accuracy_kspace_6 = -1.0;
two_charge_force = force->qqr2e *
(force->qelectron * force->qelectron) /
(force->angstrom * force->angstrom);
neighrequest_flag = 1;
mixflag = 0;
splittol = 1.0e-6;
maxeatom = maxvatom = 0;
eatom = NULL;
vatom = NULL;
datamask = ALL_MASK;
datamask_ext = ALL_MASK;
memory->create(gcons,7,7,"kspace:gcons");
gcons[2][0] = 15.0 / 8.0;
gcons[2][1] = -5.0 / 4.0;
gcons[2][2] = 3.0 / 8.0;
gcons[3][0] = 35.0 / 16.0;
gcons[3][1] = -35.0 / 16.0;
gcons[3][2] = 21.0 / 16.0;
gcons[3][3] = -5.0 / 16.0;
gcons[4][0] = 315.0 / 128.0;
gcons[4][1] = -105.0 / 32.0;
gcons[4][2] = 189.0 / 64.0;
gcons[4][3] = -45.0 / 32.0;
gcons[4][4] = 35.0 / 128.0;
gcons[5][0] = 693.0 / 256.0;
gcons[5][1] = -1155.0 / 256.0;
gcons[5][2] = 693.0 / 128.0;
gcons[5][3] = -495.0 / 128.0;
gcons[5][4] = 385.0 / 256.0;
gcons[5][5] = -63.0 / 256.0;
gcons[6][0] = 3003.0 / 1024.0;
gcons[6][1] = -3003.0 / 512.0;
gcons[6][2] = 9009.0 / 1024.0;
gcons[6][3] = -2145.0 / 256.0;
gcons[6][4] = 5005.0 / 1024.0;
gcons[6][5] = -819.0 / 512.0;
gcons[6][6] = 231.0 / 1024.0;
memory->create(dgcons,7,6,"kspace:dgcons");
dgcons[2][0] = -5.0 / 2.0;
dgcons[2][1] = 3.0 / 2.0;
dgcons[3][0] = -35.0 / 8.0;
dgcons[3][1] = 21.0 / 4.0;
dgcons[3][2] = -15.0 / 8.0;
dgcons[4][0] = -105.0 / 16.0;
dgcons[4][1] = 189.0 / 16.0;
dgcons[4][2] = -135.0 / 16.0;
dgcons[4][3] = 35.0 / 16.0;
dgcons[5][0] = -1155.0 / 128.0;
dgcons[5][1] = 693.0 / 32.0;
dgcons[5][2] = -1485.0 / 64.0;
dgcons[5][3] = 385.0 / 32.0;
dgcons[5][4] = -315.0 / 128.0;
dgcons[6][0] = -3003.0 / 256.0;
dgcons[6][1] = 9009.0 / 256.0;
dgcons[6][2] = -6435.0 / 128.0;
dgcons[6][3] = 5005.0 / 128.0;
dgcons[6][4] = -4095.0 / 256.0;
dgcons[6][5] = 693.0 / 256.0;
}
/* ---------------------------------------------------------------------- */
KSpace::~KSpace()
{
memory->destroy(eatom);
memory->destroy(vatom);
memory->destroy(gcons);
memory->destroy(dgcons);
}
/* ---------------------------------------------------------------------- */
void KSpace::triclinic_check()
{
if (domain->triclinic && triclinic_support != 1)
error->all(FLERR,"KSpace style does not yet support triclinic geometries");
}
/* ---------------------------------------------------------------------- */
void KSpace::compute_dummy(int eflag, int vflag)
{
if (eflag || vflag) ev_setup(eflag,vflag);
else evflag = evflag_atom = eflag_global = vflag_global =
eflag_atom = vflag_atom = 0;
}
/* ----------------------------------------------------------------------
check that pair style is compatible with long-range solver
------------------------------------------------------------------------- */
void KSpace::pair_check()
{
if (force->pair == NULL)
error->all(FLERR,"KSpace solver requires a pair style");
if (ewaldflag && force->pair->ewaldflag == 0)
error->all(FLERR,"KSpace style is incompatible with Pair style");
if (pppmflag && force->pair->pppmflag == 0)
error->all(FLERR,"KSpace style is incompatible with Pair style");
if (msmflag && force->pair->msmflag == 0)
error->all(FLERR,"KSpace style is incompatible with Pair style");
if (dispersionflag && force->pair->dispersionflag == 0)
error->all(FLERR,"KSpace style is incompatible with Pair style");
if (tip4pflag && force->pair->tip4pflag == 0)
error->all(FLERR,"KSpace style is incompatible with Pair style");
if (dipoleflag && force->pair->dipoleflag == 0)
error->all(FLERR,"KSpace style is incompatible with Pair style");
}
/* ----------------------------------------------------------------------
setup for energy, virial computation
see integrate::ev_set() for values of eflag (0-3) and vflag (0-6)
------------------------------------------------------------------------- */
void KSpace::ev_setup(int eflag, int vflag)
{
int i,n;
evflag = 1;
eflag_either = eflag;
eflag_global = eflag % 2;
eflag_atom = eflag / 2;
vflag_either = vflag;
vflag_global = vflag % 4;
vflag_atom = vflag / 4;
if (eflag_atom || vflag_atom) evflag_atom = 1;
else evflag_atom = 0;
// reallocate per-atom arrays if necessary
if (eflag_atom && atom->nmax > maxeatom) {
maxeatom = atom->nmax;
memory->destroy(eatom);
memory->create(eatom,maxeatom,"kspace:eatom");
}
if (vflag_atom && atom->nmax > maxvatom) {
maxvatom = atom->nmax;
memory->destroy(vatom);
memory->create(vatom,maxvatom,6,"kspace:vatom");
}
// zero accumulators
if (eflag_global) energy = 0.0;
if (vflag_global) for (i = 0; i < 6; i++) virial[i] = 0.0;
if (eflag_atom) {
n = atom->nlocal;
if (tip4pflag) n += atom->nghost;
for (i = 0; i < n; i++) eatom[i] = 0.0;
}
if (vflag_atom) {
n = atom->nlocal;
if (tip4pflag) n += atom->nghost;
for (i = 0; i < n; i++) {
vatom[i][0] = 0.0;
vatom[i][1] = 0.0;
vatom[i][2] = 0.0;
vatom[i][3] = 0.0;
vatom[i][4] = 0.0;
vatom[i][5] = 0.0;
}
}
}
/* ----------------------------------------------------------------------
compute qsum,qsqsum,q2 and give error/warning if not charge neutral
only called initially or when particle count changes
------------------------------------------------------------------------- */
void KSpace::qsum_qsq(int flag)
{
qsum = qsqsum = 0.0;
for (int i = 0; i < atom->nlocal; i++) {
qsum += atom->q[i];
qsqsum += atom->q[i]*atom->q[i];
}
double tmp;
MPI_Allreduce(&qsum,&tmp,1,MPI_DOUBLE,MPI_SUM,world);
qsum = tmp;
MPI_Allreduce(&qsqsum,&tmp,1,MPI_DOUBLE,MPI_SUM,world);
qsqsum = tmp;
if (qsqsum == 0.0)
error->all(FLERR,"Cannot use kspace solver on system with no charge");
q2 = qsqsum * force->qqrd2e;
// not yet sure of the correction needed for non-neutral systems
if (fabs(qsum) > SMALL) {
char str[128];
sprintf(str,"System is not charge neutral, net charge = %g",qsum);
if (flag) error->all(FLERR,str);
else if (comm->me == 0) error->warning(FLERR,str);
}
}
/* ----------------------------------------------------------------------
estimate the accuracy of the short-range coulomb tables
------------------------------------------------------------------------- */
double KSpace::estimate_table_accuracy(double q2_over_sqrt, double spr)
{
double table_accuracy = 0.0;
int nctb = force->pair->ncoultablebits;
if (nctb) {
double empirical_precision[17];
empirical_precision[6] = 6.99E-03;
empirical_precision[7] = 1.78E-03;
empirical_precision[8] = 4.72E-04;
empirical_precision[9] = 1.17E-04;
empirical_precision[10] = 2.95E-05;
empirical_precision[11] = 7.41E-06;
empirical_precision[12] = 1.76E-06;
empirical_precision[13] = 9.28E-07;
empirical_precision[14] = 7.46E-07;
empirical_precision[15] = 7.32E-07;
empirical_precision[16] = 7.30E-07;
if (nctb <= 6) table_accuracy = empirical_precision[6];
else if (nctb <= 16) table_accuracy = empirical_precision[nctb];
else table_accuracy = empirical_precision[16];
table_accuracy *= q2_over_sqrt;
if ((table_accuracy > spr) && (comm->me == 0))
error->warning(FLERR,"For better accuracy use 'pair_modify table 0'");
}
return table_accuracy;
}
/* ----------------------------------------------------------------------
convert box coords vector to transposed triclinic lamda (0-1) coords
vector, lamda = [(H^-1)^T] * v, does not preserve vector magnitude
v and lamda can point to same 3-vector
------------------------------------------------------------------------- */
void KSpace::x2lamdaT(double *v, double *lamda)
{
double *h_inv = domain->h_inv;
double lamda_tmp[3];
lamda_tmp[0] = h_inv[0]*v[0];
lamda_tmp[1] = h_inv[5]*v[0] + h_inv[1]*v[1];
lamda_tmp[2] = h_inv[4]*v[0] + h_inv[3]*v[1] + h_inv[2]*v[2];
lamda[0] = lamda_tmp[0];
lamda[1] = lamda_tmp[1];
lamda[2] = lamda_tmp[2];
}
/* ----------------------------------------------------------------------
convert lamda (0-1) coords vector to transposed box coords vector
lamda = (H^T) * v, does not preserve vector magnitude
v and lamda can point to same 3-vector
------------------------------------------------------------------------- */
void KSpace::lamda2xT(double *lamda, double *v)
{
double *h = domain->h;
double v_tmp[3];
v_tmp[0] = h[0]*lamda[0];
v_tmp[1] = h[5]*lamda[0] + h[1]*lamda[1];
v_tmp[2] = h[4]*lamda[0] + h[3]*lamda[1] + h[2]*lamda[2];
v[0] = v_tmp[0];
v[1] = v_tmp[1];
v[2] = v_tmp[2];
}
/* ----------------------------------------------------------------------
convert triclinic lamda (0-1) coords vector to box coords vector
v = H * lamda, does not preserve vector magnitude
lamda and v can point to same 3-vector
------------------------------------------------------------------------- */
void KSpace::lamda2xvector(double *lamda, double *v)
{
double *h = domain->h;
v[0] = h[0]*lamda[0] + h[5]*lamda[1] + h[4]*lamda[2];
v[1] = h[1]*lamda[1] + h[3]*lamda[2];
v[2] = h[2]*lamda[2];
}
/* ----------------------------------------------------------------------
convert a sphere in box coords to an ellipsoid in lamda (0-1)
coords and return the tight (axis-aligned) bounding box, does not
preserve vector magnitude
see http://www.loria.fr/~shornus/ellipsoid-bbox.html and
http://yiningkarlli.blogspot.com/2013/02/
bounding-boxes-for-ellipsoidsfigure.html
------------------------------------------------------------------------- */
void KSpace::kspacebbox(double r, double *b)
{
double *h = domain->h;
double lx,ly,lz,xy,xz,yz;
lx = h[0];
ly = h[1];
lz = h[2];
yz = h[3];
xz = h[4];
xy = h[5];
b[0] = r*sqrt(ly*ly*lz*lz + ly*ly*xz*xz - 2.0*ly*xy*xz*yz + lz*lz*xy*xy +
xy*xy*yz*yz)/(lx*ly*lz);
b[1] = r*sqrt(lz*lz + yz*yz)/(ly*lz);
b[2] = r/lz;
}
/* ----------------------------------------------------------------------
modify parameters of the KSpace style
------------------------------------------------------------------------- */
void KSpace::modify_params(int narg, char **arg)
{
int iarg = 0;
while (iarg < narg) {
if (strcmp(arg[iarg],"mesh") == 0) {
if (iarg+4 > narg) error->all(FLERR,"Illegal kspace_modify command");
nx_pppm = nx_msm_max = force->inumeric(FLERR,arg[iarg+1]);
ny_pppm = ny_msm_max = force->inumeric(FLERR,arg[iarg+2]);
nz_pppm = nz_msm_max = force->inumeric(FLERR,arg[iarg+3]);
if (nx_pppm == 0 && ny_pppm == 0 && nz_pppm == 0) gridflag = 0;
else gridflag = 1;
iarg += 4;
} else if (strcmp(arg[iarg],"mesh/disp") == 0) {
if (iarg+4 > narg) error->all(FLERR,"Illegal kspace_modify command");
nx_pppm_6 = force->inumeric(FLERR,arg[iarg+1]);
ny_pppm_6 = force->inumeric(FLERR,arg[iarg+2]);
nz_pppm_6 = force->inumeric(FLERR,arg[iarg+3]);
if (nx_pppm_6 == 0 || ny_pppm_6 == 0 || nz_pppm_6 == 0) gridflag_6 = 0;
else gridflag_6 = 1;
iarg += 4;
} else if (strcmp(arg[iarg],"order") == 0) {
if (iarg+2 > narg) error->all(FLERR,"Illegal kspace_modify command");
order = force->inumeric(FLERR,arg[iarg+1]);
iarg += 2;
} else if (strcmp(arg[iarg],"order/disp") == 0) {
if (iarg+2 > narg) error->all(FLERR,"Illegal kspace_modify command");
order_6 = force->inumeric(FLERR,arg[iarg+1]);
iarg += 2;
} else if (strcmp(arg[iarg],"minorder") == 0) {
if (iarg+2 > narg) error->all(FLERR,"Illegal kspace_modify command");
minorder = force->inumeric(FLERR,arg[iarg+1]);
if (minorder < 2) error->all(FLERR,"Illegal kspace_modify command");
iarg += 2;
} else if (strcmp(arg[iarg],"overlap") == 0) {
if (iarg+2 > narg) error->all(FLERR,"Illegal kspace_modify command");
if (strcmp(arg[iarg+1],"yes") == 0) overlap_allowed = 1;
else if (strcmp(arg[iarg+1],"no") == 0) overlap_allowed = 0;
else error->all(FLERR,"Illegal kspace_modify command");
iarg += 2;
} else if (strcmp(arg[iarg],"force") == 0) {
if (iarg+2 > narg) error->all(FLERR,"Illegal kspace_modify command");
accuracy_absolute = force->numeric(FLERR,arg[iarg+1]);
iarg += 2;
} else if (strcmp(arg[iarg],"gewald") == 0) {
if (iarg+2 > narg) error->all(FLERR,"Illegal kspace_modify command");
g_ewald = force->numeric(FLERR,arg[iarg+1]);
if (g_ewald == 0.0) gewaldflag = 0;
else gewaldflag = 1;
iarg += 2;
} else if (strcmp(arg[iarg],"gewald/disp") == 0) {
if (iarg+2 > narg) error->all(FLERR,"Illegal kspace_modify command");
g_ewald_6 = force->numeric(FLERR,arg[iarg+1]);
if (g_ewald_6 == 0.0) gewaldflag_6 = 0;
else gewaldflag_6 = 1;
iarg += 2;
} else if (strcmp(arg[iarg],"slab") == 0) {
if (iarg+2 > narg) error->all(FLERR,"Illegal kspace_modify command");
if (strcmp(arg[iarg+1],"nozforce") == 0) {
slabflag = 2;
} else {
slabflag = 1;
slab_volfactor = force->numeric(FLERR,arg[iarg+1]);
if (slab_volfactor <= 1.0)
error->all(FLERR,"Bad kspace_modify slab parameter");
if (slab_volfactor < 2.0 && comm->me == 0)
error->warning(FLERR,"Kspace_modify slab param < 2.0 may "
"cause unphysical behavior");
}
iarg += 2;
} else if (strcmp(arg[iarg],"compute") == 0) {
if (iarg+2 > narg) error->all(FLERR,"Illegal kspace_modify command");
if (strcmp(arg[iarg+1],"yes") == 0) compute_flag = 1;
else if (strcmp(arg[iarg+1],"no") == 0) compute_flag = 0;
else error->all(FLERR,"Illegal kspace_modify command");
iarg += 2;
} else if (strcmp(arg[iarg],"fftbench") == 0) {
if (iarg+2 > narg) error->all(FLERR,"Illegal kspace_modify command");
if (strcmp(arg[iarg+1],"yes") == 0) fftbench = 1;
else if (strcmp(arg[iarg+1],"no") == 0) fftbench = 0;
else error->all(FLERR,"Illegal kspace_modify command");
iarg += 2;
} else if (strcmp(arg[iarg],"collective") == 0) {
if (iarg+2 > narg) error->all(FLERR,"Illegal kspace_modify command");
if (strcmp(arg[iarg+1],"yes") == 0) collective_flag = 1;
else if (strcmp(arg[iarg+1],"no") == 0) collective_flag = 0;
else error->all(FLERR,"Illegal kspace_modify command");
iarg += 2;
} else if (strcmp(arg[iarg],"diff") == 0) {
if (iarg+2 > narg) error->all(FLERR,"Illegal kspace_modify command");
if (strcmp(arg[iarg+1],"ad") == 0) differentiation_flag = 1;
else if (strcmp(arg[iarg+1],"ik") == 0) differentiation_flag = 0;
else error->all(FLERR, "Illegal kspace_modify command");
iarg += 2;
} else if (strcmp(arg[iarg],"cutoff/adjust") == 0) {
if (iarg+2 > narg) error->all(FLERR,"Illegal kspace_modify command");
if (strcmp(arg[iarg+1],"yes") == 0) adjust_cutoff_flag = 1;
else if (strcmp(arg[iarg+1],"no") == 0) adjust_cutoff_flag = 0;
else error->all(FLERR,"Illegal kspace_modify command");
iarg += 2;
} else if (strcmp(arg[iarg],"kmax/ewald") == 0) {
if (iarg+4 > narg) error->all(FLERR,"Illegal kspace_modify command");
kx_ewald = atoi(arg[iarg+1]);
ky_ewald = atoi(arg[iarg+2]);
kz_ewald = atoi(arg[iarg+3]);
if (kx_ewald < 0 || ky_ewald < 0 || kz_ewald < 0)
error->all(FLERR,"Bad kspace_modify kmax/ewald parameter");
if (kx_ewald > 0 && ky_ewald > 0 && kz_ewald > 0)
kewaldflag = 1;
else
kewaldflag = 0;
iarg += 4;
} else if (strcmp(arg[iarg],"mix/disp") == 0) {
if (iarg+2 > narg) error->all(FLERR,"Illegal kspace_modify command");
if (strcmp(arg[iarg+1],"pair") == 0) mixflag = 0;
else if (strcmp(arg[iarg+1],"geom") == 0) mixflag = 1;
else if (strcmp(arg[iarg+1],"none") == 0) mixflag = 2;
else error->all(FLERR,"Illegal kspace_modify command");
iarg += 2;
} else if (strcmp(arg[iarg],"force/disp/real") == 0) {
if (iarg+2 > narg) error->all(FLERR,"Illegal kspace_modify command");
accuracy_real_6 = atof(arg[iarg+1]);
iarg += 2;
} else if (strcmp(arg[iarg],"force/disp/kspace") == 0) {
if (iarg+2 > narg) error->all(FLERR,"Illegal kspace_modify command");
accuracy_kspace_6 = atof(arg[iarg+1]);
iarg += 2;
} else if (strcmp(arg[iarg],"eigtol") == 0) {
if (iarg+2 > narg) error->all(FLERR,"Illegal kspace_modify command");
splittol = atof(arg[iarg+1]);
if (splittol >= 1.0)
error->all(FLERR,"Kspace_modify eigtol must be smaller than one");
iarg += 2;
} else if (strcmp(arg[iarg],"pressure/scalar") == 0) {
if (iarg+2 > narg) error->all(FLERR,"Illegal kspace_modify command");
if (strcmp(arg[iarg+1],"yes") == 0) scalar_pressure_flag = 1;
else if (strcmp(arg[iarg+1],"no") == 0) scalar_pressure_flag = 0;
else error->all(FLERR,"Illegal kspace_modify command");
iarg += 2;
} else error->all(FLERR,"Illegal kspace_modify command");
}
}
/* ---------------------------------------------------------------------- */
void *KSpace::extract(const char *str)
{
if (strcmp(str,"scale") == 0) return (void *) &scale;
return NULL;
}
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