Files
lammps/src/ML-SNAP/compute_sna_atom.cpp
2024-02-28 15:37:13 -05:00

670 lines
20 KiB
C++

// clang-format off
/* ----------------------------------------------------------------------
LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
https://www.lammps.org/, Sandia National Laboratories
LAMMPS development team: developers@lammps.org
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 "compute_sna_atom.h"
#include "sna.h"
#include "atom.h"
#include "update.h"
#include "modify.h"
#include "neighbor.h"
#include "neigh_list.h"
#include "force.h"
#include "pair.h"
#include "comm.h"
#include "memory.h"
#include "error.h"
#include <cmath>
#include <cstring>
using namespace LAMMPS_NS;
ComputeSNAAtom::ComputeSNAAtom(LAMMPS *lmp, int narg, char **arg) :
Compute(lmp, narg, arg), cutsq(nullptr), list(nullptr), sna(nullptr),
radelem(nullptr), wjelem(nullptr), sinnerelem(nullptr), dinnerelem(nullptr)
{
// begin code common to all SNAP computes
double rfac0, rmin0;
int twojmax, switchflag, bzeroflag, bnormflag, wselfallflag;
int ntypes = atom->ntypes;
int nargmin = 6 + 2 * ntypes;
if (narg < nargmin) error->all(FLERR, "Illegal compute {} command", style);
// default values
rmin0 = 0.0;
switchflag = 1;
bzeroflag = 1;
quadraticflag = 0;
chemflag = 0;
bnormflag = 0;
wselfallflag = 0;
switchinnerflag = 0;
nelements = 1;
nnn = 12;
wmode = 0;
delta = 1.e-3;
nearest_neighbors_mode = false;
// process required arguments
memory->create(radelem, ntypes + 1, "sna/atom:radelem"); // offset by 1 to match up with types
memory->create(wjelem, ntypes + 1, "sna/atom:wjelem");
rcutfac = utils::numeric(FLERR, arg[3], false, lmp);
rfac0 = utils::numeric(FLERR, arg[4], false, lmp);
twojmax = utils::inumeric(FLERR, arg[5], false, lmp);
for (int i = 0; i < ntypes; i++)
radelem[i + 1] =
utils::numeric(FLERR, arg[6 + i], false, lmp);
for (int i = 0; i < ntypes; i++)
wjelem[i + 1] =
utils::numeric(FLERR, arg[6 + ntypes + i], false, lmp);
// construct cutsq
double cut;
cutmax = 0.0;
memory->create(cutsq, ntypes + 1, ntypes + 1, "sna/atom:cutsq");
for (int i = 1; i <= ntypes; i++) {
cut = 2.0 * radelem[i] * rcutfac;
if (cut > cutmax) cutmax = cut;
cutsq[i][i] = cut * cut;
for (int j = i + 1; j <= ntypes; j++) {
cut = (radelem[i] + radelem[j]) * rcutfac;
cutsq[i][j] = cutsq[j][i] = cut * cut;
}
}
// set local input checks
int sinnerflag = 0;
int dinnerflag = 0;
// process optional args
int iarg = nargmin;
while (iarg < narg) {
if (strcmp(arg[iarg], "rmin0") == 0) {
if (iarg + 2 > narg) error->all(FLERR, "Illegal compute {} command", style);
rmin0 = utils::numeric(FLERR, arg[iarg + 1], false, lmp);
iarg += 2;
} else if (strcmp(arg[iarg], "switchflag") == 0) {
if (iarg + 2 > narg) error->all(FLERR, "Illegal compute {} command", style);
switchflag = utils::inumeric(FLERR, arg[iarg + 1], false, lmp);
iarg += 2;
} else if (strcmp(arg[iarg], "bzeroflag") == 0) {
if (iarg + 2 > narg) error->all(FLERR, "Illegal compute {} command", style);
bzeroflag = utils::inumeric(FLERR, arg[iarg + 1], false, lmp);
iarg += 2;
} else if (strcmp(arg[iarg], "quadraticflag") == 0) {
if (iarg + 2 > narg) error->all(FLERR, "Illegal compute {} command", style);
quadraticflag = utils::inumeric(FLERR, arg[iarg + 1], false, lmp);
iarg += 2;
} else if (strcmp(arg[iarg],"nnn") == 0) {
if (iarg + 2 > narg) error->all(FLERR, "Illegal compute {} command", style);
nnn = utils::inumeric(FLERR, arg[iarg + 1], false, lmp);
nearest_neighbors_mode = true;
if (nnn <= 0) error->all(FLERR, "Illegal compute compute {} command", style);
iarg += 2;
} else if (strcmp(arg[iarg],"wmode") == 0) {
if (iarg + 2 > narg) error->all(FLERR, "Illegal compute {} command", style);
wmode = utils::inumeric(FLERR, arg[iarg + 1], false, lmp);
if (wmode < 0) error->all(FLERR, "Illegal compute compute {} command", style);
iarg += 2;
} else if (strcmp(arg[iarg],"delta") == 0) {
if (iarg + 2 > narg) error->all(FLERR, "Illegal compute {} command", style);
delta = utils::numeric(FLERR, arg[iarg + 1], false, lmp);
if (delta < 1.0e-3) error->all(FLERR, "Illegal compute compute {} command", style);
iarg += 2;
} else if (strcmp(arg[iarg], "chem") == 0) {
if (iarg + 2 > narg) error->all(FLERR, "Illegal compute {} command", style);
chemflag = 1;
memory->create(map, ntypes + 1, "compute_sna_grid:map");
nelements = utils::inumeric(FLERR, arg[iarg + 1], false, lmp);
for (int i = 0; i < ntypes; i++) {
int jelem = utils::inumeric(FLERR, arg[iarg + 2 + i], false, lmp);
if (jelem < 0 || jelem >= nelements) error->all(FLERR, "Illegal compute {} command", style);
map[i + 1] = jelem;
}
iarg += 2 + ntypes;
} else if (strcmp(arg[iarg], "bnormflag") == 0) {
if (iarg + 2 > narg) error->all(FLERR, "Illegal compute {} command", style);
bnormflag = utils::inumeric(FLERR, arg[iarg + 1], false, lmp);
iarg += 2;
} else if (strcmp(arg[iarg], "wselfallflag") == 0) {
if (iarg + 2 > narg) error->all(FLERR, "Illegal compute {} command", style);
wselfallflag = utils::inumeric(FLERR, arg[iarg + 1], false, lmp);
iarg += 2;
} else if (strcmp(arg[iarg], "switchinnerflag") == 0) {
if (iarg + 2 > narg) error->all(FLERR, "Illegal compute {} command", style);
switchinnerflag = utils::inumeric(FLERR, arg[iarg + 1], false, lmp);
iarg += 2;
} else if (strcmp(arg[iarg], "sinner") == 0) {
iarg++;
if (iarg + ntypes > narg) error->all(FLERR, "Illegal compute {} command", style);
memory->create(sinnerelem, ntypes + 1, "snap:sinnerelem");
for (int i = 0; i < ntypes; i++)
sinnerelem[i + 1] = utils::numeric(FLERR, arg[iarg + i], false, lmp);
sinnerflag = 1;
iarg += ntypes;
} else if (strcmp(arg[iarg], "dinner") == 0) {
iarg++;
if (iarg + ntypes > narg) error->all(FLERR, "Illegal compute {} command", style);
memory->create(dinnerelem, ntypes + 1, "snap:dinnerelem");
for (int i = 0; i < ntypes; i++)
dinnerelem[i + 1] = utils::numeric(FLERR, arg[iarg + i], false, lmp);
dinnerflag = 1;
iarg += ntypes;
} else
error->all(FLERR, "Illegal compute {} command", style);
}
if (switchinnerflag && !(sinnerflag && dinnerflag))
error->all(
FLERR,
"Illegal compute {} command: switchinnerflag = 1, missing sinner/dinner keyword",
style);
if (!switchinnerflag && (sinnerflag || dinnerflag))
error->all(
FLERR,
"Illegal compute {} command: switchinnerflag = 0, unexpected sinner/dinner keyword",
style);
snaptr = new SNA(lmp, rfac0, twojmax, rmin0, switchflag, bzeroflag, chemflag, bnormflag,
wselfallflag, nelements, switchinnerflag);
ncoeff = snaptr->ncoeff;
nvalues = ncoeff;
if (quadraticflag) nvalues += (ncoeff * (ncoeff + 1)) / 2;
// end code common to all SNAP computes
size_peratom_cols = nvalues;
peratom_flag = 1;
nmax = 0;
sna = nullptr;
}
/* ---------------------------------------------------------------------- */
ComputeSNAAtom::~ComputeSNAAtom()
{
memory->destroy(sna);
memory->destroy(radelem);
memory->destroy(wjelem);
memory->destroy(cutsq);
delete snaptr;
if (chemflag) memory->destroy(map);
if (switchinnerflag) {
memory->destroy(sinnerelem);
memory->destroy(dinnerelem);
}
}
/* ---------------------------------------------------------------------- */
void ComputeSNAAtom::init()
{
if (force->pair == nullptr)
error->all(FLERR,"Compute sna/atom requires a pair style be defined");
rcutsq = force->pair->cutforce * force->pair->cutforce;
if (cutmax > force->pair->cutforce)
error->all(FLERR,"Compute sna/atom cutoff is longer than pairwise cutoff");
// need an occasional full neighbor list
neighbor->add_request(this, NeighConst::REQ_FULL | NeighConst::REQ_OCCASIONAL);
if (modify->get_compute_by_style("sna/atom").size() > 1 && comm->me == 0)
error->warning(FLERR,"More than one compute sna/atom");
snaptr->init();
}
/* ---------------------------------------------------------------------- */
void ComputeSNAAtom::init_list(int /*id*/, NeighList *ptr)
{
list = ptr;
}
/* ---------------------------------------------------------------------- */
void ComputeSNAAtom::compute_peratom()
{
invoked_peratom = update->ntimestep;
// grow sna array if necessary
if (atom->nmax > nmax) {
memory->destroy(sna);
nmax = atom->nmax;
memory->create(sna,nmax,size_peratom_cols,"sna/atom:sna");
array_atom = sna;
}
// invoke full neighbor list (will copy or build if necessary)
neighbor->build_one(list);
const int inum = list->inum;
const int* const ilist = list->ilist;
const int* const numneigh = list->numneigh;
int** const firstneigh = list->firstneigh;
int * const type = atom->type;
// compute sna for each atom in group
// use full neighbor list to count atoms less than cutoff
double** const x = atom->x;
const int* const mask = atom->mask;
for (int ii = 0; ii < inum; ii++) {
const int i = ilist[ii];
if (mask[i] & groupbit) {
const double xtmp = x[i][0];
const double ytmp = x[i][1];
const double ztmp = x[i][2];
const int itype = type[i];
int ielem = 0;
if (chemflag)
ielem = map[itype];
const double radi = radelem[itype];
const int* const jlist = firstneigh[i];
const int jnum = numneigh[i];
// ############################################################################## //
// ##### Start of section for computing bispectrum on nnn nearest neighbors ##### //
// ############################################################################## //
if (nearest_neighbors_mode) {
// ##### 1) : consider full neighbor list in rlist
memory->create(distsq, jnum, "snann/atom:distsq");
memory->create(rlist, jnum, 3, "snann/atom:rlist");
int ncount = 0;
for (int jj = 0; jj < jnum; jj++) {
int j = jlist[jj];
j &= NEIGHMASK;
const double delx = xtmp - x[j][0];
const double dely = ytmp - x[j][1];
const double delz = ztmp - x[j][2];
const double rsq = delx * delx + dely * dely + delz * delz;
if (rsq < rcutsq) {
distsq[ncount] = rsq;
rlist[ncount][0] = delx;
rlist[ncount][1] = dely;
rlist[ncount][2] = delz;
ncount++;
}
}
// ##### 2) : compute optimal cutoff such that sum weights S_target = nnn
double S_target=1.*nnn;
double rc_start=0.1;
double rc_max=sqrt(rcutsq);
double tol=1.e-8;
double * sol_dich = dichotomie(S_target, rc_start, rc_max, tol, distsq, ncount, wmode, delta);
memory->destroy(distsq);
// ##### 3) : assign that optimal cutoff radius to bispectrum context using rcsol
double rcsol = (sol_dich[0]+sol_dich[1])/2.;
memory->destroy(sol_dich);
snaptr->grow_rij(ncount);
int ninside = 0;
for (int jj = 0; jj < ncount; jj++) {
int j = jlist[jj];
j &= NEIGHMASK;
const double rsq = rlist[jj][0]*rlist[jj][0]+rlist[jj][1]*rlist[jj][1]+rlist[jj][2]*rlist[jj][2];
int jtype = type[j];
int jelem = 0;
if (chemflag)
jelem = map[jtype];
if (rsq < rcsol*rcsol) {
snaptr->rij[ninside][0] = rlist[jj][0];//rijmax;
snaptr->rij[ninside][1] = rlist[jj][1];//rijmax;
snaptr->rij[ninside][2] = rlist[jj][2];//rijmax;
snaptr->inside[ninside] = j;
snaptr->wj[ninside] = 1.;
snaptr->rcutij[ninside] = rcsol;
if (switchinnerflag) {
snaptr->sinnerij[ninside] = 0.5*(sinnerelem[itype]+sinnerelem[jtype]);
snaptr->dinnerij[ninside] = 0.5*(dinnerelem[itype]+dinnerelem[jtype]);
}
if (chemflag) snaptr->element[ninside] = jelem;
ninside++;
}
}
memory->destroy(rlist);
// ############################################################################ //
// ##### End of section for computing bispectrum on nnn nearest neighbors ##### //
// ############################################################################ //
snaptr->compute_ui(ninside, ielem);
snaptr->compute_zi();
snaptr->compute_bi(ielem);
for (int icoeff = 0; icoeff < ncoeff; icoeff++)
sna[i][icoeff] = snaptr->blist[icoeff];
if (quadraticflag) {
int ncount = ncoeff;
for (int icoeff = 0; icoeff < ncoeff; icoeff++) {
double bi = snaptr->blist[icoeff];
// diagonal element of quadratic matrix
sna[i][ncount++] = 0.5*bi*bi;
// upper-triangular elements of quadratic matrix
for (int jcoeff = icoeff+1; jcoeff < ncoeff; jcoeff++)
sna[i][ncount++] = bi*snaptr->blist[jcoeff];
}
}
} else {
// ensure rij, inside, and typej are of size jnum
snaptr->grow_rij(jnum);
// rij[][3] = displacements between atom I and those neighbors
// inside = indices of neighbors of I within cutoff
// typej = types of neighbors of I within cutoff
int ninside = 0;
for (int jj = 0; jj < jnum; jj++) {
int j = jlist[jj];
j &= NEIGHMASK;
const double delx = xtmp - x[j][0];
const double dely = ytmp - x[j][1];
const double delz = ztmp - x[j][2];
const double rsq = delx*delx + dely*dely + delz*delz;
int jtype = type[j];
int jelem = 0;
if (chemflag)
jelem = map[jtype];
if (rsq < cutsq[itype][jtype] && rsq>1e-20) {
snaptr->rij[ninside][0] = delx;
snaptr->rij[ninside][1] = dely;
snaptr->rij[ninside][2] = delz;
snaptr->inside[ninside] = j;
snaptr->wj[ninside] = wjelem[jtype];
snaptr->rcutij[ninside] = (radi+radelem[jtype])*rcutfac;
if (switchinnerflag) {
snaptr->sinnerij[ninside] = 0.5*(sinnerelem[itype]+sinnerelem[jtype]);
snaptr->dinnerij[ninside] = 0.5*(dinnerelem[itype]+dinnerelem[jtype]);
}
if (chemflag) snaptr->element[ninside] = jelem;
ninside++;
}
}
snaptr->compute_ui(ninside, ielem);
snaptr->compute_zi();
snaptr->compute_bi(ielem);
for (int icoeff = 0; icoeff < ncoeff; icoeff++)
sna[i][icoeff] = snaptr->blist[icoeff];
if (quadraticflag) {
int ncount = ncoeff;
for (int icoeff = 0; icoeff < ncoeff; icoeff++) {
double bi = snaptr->blist[icoeff];
// diagonal element of quadratic matrix
sna[i][ncount++] = 0.5*bi*bi;
// upper-triangular elements of quadratic matrix
for (int jcoeff = icoeff+1; jcoeff < ncoeff; jcoeff++)
sna[i][ncount++] = bi*snaptr->blist[jcoeff];
}
}
}
} else {
for (int icoeff = 0; icoeff < size_peratom_cols; icoeff++)
sna[i][icoeff] = 0.0;
}
}
}
/* ----------------------------------------------------------------------
memory usage
------------------------------------------------------------------------- */
double ComputeSNAAtom::memory_usage()
{
double bytes = (double)nmax*size_peratom_cols * sizeof(double); // sna
bytes += snaptr->memory_usage(); // SNA object
return bytes;
}
/* ----------------------------------------------------------------------
select3 routine from Numerical Recipes (slightly modified)
find k smallest values in array of length n
sort auxiliary arrays at same time
------------------------------------------------------------------------- */
// Use no-op do while to create single statement
#define SWAP(a, b) \
do { \
tmp = a; \
(a) = b; \
(b) = tmp; \
} while (0)
#define ISWAP(a, b) \
do { \
itmp = a; \
(a) = b; \
(b) = itmp; \
} while (0)
#define SWAP3(a, b) \
do { \
tmp = (a)[0]; \
(a)[0] = (b)[0]; \
(b)[0] = tmp; \
tmp = (a)[1]; \
(a)[1] = (b)[1]; \
(b)[1] = tmp; \
tmp = (a)[2]; \
(a)[2] = (b)[2]; \
(b)[2] = tmp; \
} while (0)
/* ---------------------------------------------------------------------- */
void ComputeSNAAtom::select3(int k, int n, double *arr, int *iarr, double **arr3)
{
int i, ir, j, l, mid, ia, itmp;
double a, tmp, a3[3];
arr--;
iarr--;
arr3--;
l = 1;
ir = n;
for (;;) {
if (ir <= l + 1) {
if (ir == l + 1 && arr[ir] < arr[l]) {
SWAP(arr[l], arr[ir]);
ISWAP(iarr[l], iarr[ir]);
SWAP3(arr3[l], arr3[ir]);
}
return;
} else {
mid = (l + ir) >> 1;
SWAP(arr[mid], arr[l + 1]);
ISWAP(iarr[mid], iarr[l + 1]);
SWAP3(arr3[mid], arr3[l + 1]);
if (arr[l] > arr[ir]) {
SWAP(arr[l], arr[ir]);
ISWAP(iarr[l], iarr[ir]);
SWAP3(arr3[l], arr3[ir]);
}
if (arr[l + 1] > arr[ir]) {
SWAP(arr[l + 1], arr[ir]);
ISWAP(iarr[l + 1], iarr[ir]);
SWAP3(arr3[l + 1], arr3[ir]);
}
if (arr[l] > arr[l + 1]) {
SWAP(arr[l], arr[l + 1]);
ISWAP(iarr[l], iarr[l + 1]);
SWAP3(arr3[l], arr3[l + 1]);
}
i = l + 1;
j = ir;
a = arr[l + 1];
ia = iarr[l + 1];
a3[0] = arr3[l + 1][0];
a3[1] = arr3[l + 1][1];
a3[2] = arr3[l + 1][2];
for (;;) {
do i++;
while (arr[i] < a);
do j--;
while (arr[j] > a);
if (j < i) break;
SWAP(arr[i], arr[j]);
ISWAP(iarr[i], iarr[j]);
SWAP3(arr3[i], arr3[j]);
}
arr[l + 1] = arr[j];
arr[j] = a;
iarr[l + 1] = iarr[j];
iarr[j] = ia;
arr3[l + 1][0] = arr3[j][0];
arr3[l + 1][1] = arr3[j][1];
arr3[l + 1][2] = arr3[j][2];
arr3[j][0] = a3[0];
arr3[j][1] = a3[1];
arr3[j][2] = a3[2];
if (j >= k) ir = j - 1;
if (j <= k) l = i;
}
}
}
double *ComputeSNAAtom::weights(double *rsq, double rcut, int ncounts)
{
double *w=nullptr;
memory->destroy(w);
memory->create(w, ncounts, "snann:gauss_weights");
double rloc=0.;
for (int i=0; i<ncounts; i++) {
rloc = sqrt(rsq[i]);
if (rloc > rcut){
w[i]=0.;
} else {
w[i]=1.;
}
}
return w;
}
double *ComputeSNAAtom::tanh_weights(double *rsq, double rcut, double delta, int ncounts)
{
double *w=nullptr;
memory->destroy(w);
memory->create(w, ncounts, "snann:gauss_weights");
double rloc=0.;
for (int i=0; i<ncounts; i++) {
rloc = sqrt(rsq[i]);
w[i] = 0.5*(1.-tanh((rloc-rcut)/delta));
}
return w;
}
double ComputeSNAAtom::sum_weights(double * /*rsq*/, double *w, int ncounts)
{
double S=0.0;
for (int i=0; i<ncounts; i++) {
S += w[i];
}
return S;
}
double ComputeSNAAtom::get_target_rcut(double S_target, double *rsq, double rcut, int ncounts,
int weightmode, double delta)
{
double S_sol = 0.0;
if (weightmode == 0) {
double *www = weights(rsq, rcut, ncounts);
S_sol = sum_weights(rsq, www, ncounts);
memory->destroy(www);
} else if (weightmode == 1) {
double *www = tanh_weights(rsq, rcut, delta, ncounts);
S_sol = sum_weights(rsq, www, ncounts);
memory->destroy(www);
}
double err = S_sol - S_target;
return err;
}
double *ComputeSNAAtom::dichotomie(double S_target, double a, double b, double e, double *rsq,
int ncounts, int weightmode, double delta)
{
double d=b-a;
double *sol = nullptr;
memory->destroy(sol);
memory->create(sol, 2, "snann:sol");
double m=0.0;
do {
m = (a + b) / 2.0;
d = fabs(b - a);
double f_ra = get_target_rcut(S_target, rsq, a, ncounts, weightmode, delta);
double f_rm = get_target_rcut(S_target, rsq, m, ncounts, weightmode, delta);
if (f_rm == 0.0) {
sol[0]=m;
sol[1]=m;
return sol;
} else if (f_rm*f_ra > 0.0) {
a = m;
} else {
b = m;
}
} while (d > e);
sol[0]=a;
sol[1]=b;
return sol;
}