Files
lammps/src/npair_bin_atomonly.cpp
2022-08-04 14:05:18 -06:00

149 lines
4.6 KiB
C++

// clang-format off
/* ----------------------------------------------------------------------
LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
https://www.lammps.org/, 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 "npair_bin_atomonly.h"
#include "atom.h"
#include "error.h"
#include "neighbor.h"
#include "my_page.h"
#include "neigh_list.h"
using namespace LAMMPS_NS;
using namespace NeighConst;
/* ---------------------------------------------------------------------- */
template<int HALF, int NEWTON, int TRI>
NPairBinAtomonly<HALF, NEWTON, TRI>::NPairBinAtomonly(LAMMPS *lmp) : NPair(lmp) {}
/* ----------------------------------------------------------------------
binned neighbor list construction for all neighbors
every neighbor pair appears in list of both atoms i and j
------------------------------------------------------------------------- */
template<int HALF, int NEWTON, int TRI>
void NPairBinAtomonly<HALF, NEWTON, TRI>::build(NeighList *list)
{
int i,j,k,n,itype,jtype,ibin,bin_start;
double xtmp,ytmp,ztmp,delx,dely,delz,rsq;
int *neighptr;
double **x = atom->x;
int *type = atom->type;
int *mask = atom->mask;
tagint *molecule = atom->molecule;
int nlocal = atom->nlocal;
if (includegroup) nlocal = atom->nfirst;
int *ilist = list->ilist;
int *numneigh = list->numneigh;
int **firstneigh = list->firstneigh;
MyPage<int> *ipage = list->ipage;
int inum = 0;
ipage->reset();
for (i = 0; i < nlocal; i++) {
n = 0;
neighptr = ipage->vget();
itype = type[i];
xtmp = x[i][0];
ytmp = x[i][1];
ztmp = x[i][2];
ibin = atom2bin[i];
for (k = 0; k < nstencil; k++) {
bin_start = binhead[ibin+stencil[k]];
if (stencil[k] == 0) {
if (HALF && NEWTON && (!TRI)) {
// Half neighbor list, newton on, orthonormal
// loop over rest of atoms in i's bin, ghosts are at end of linked list
bin_start = bins[i];
}
}
for (j = bin_start; j >= 0; j = bins[j]) {
if (!HALF) {
// Full neighbor list
// only skip i = j
if (i == j) continue;
} else if (!NEWTON) {
// Half neighbor list, newton off
// only store pair if i < j
// stores own/own pairs only once
// stores own/ghost pairs on both procs
if (j <= i) continue;
} else if (TRI) {
// Half neighbor list, newton on, triclinic
// pairs for atoms j "below" i are excluded
// below = lower z or (equal z and lower y) or (equal zy and lower x)
// (equal zyx and j <= i)
// latter excludes self-self interaction but allows superposed atoms
if (x[j][2] < ztmp) continue;
if (x[j][2] == ztmp) {
if (x[j][1] < ytmp) continue;
if (x[j][1] == ytmp) {
if (x[j][0] < xtmp) continue;
if (x[j][0] == xtmp && j <= i) continue;
}
}
} else {
// Half neighbor list, newton on, orthonormal
// store every pair for every bin in stencil,except for i's bin
if (stencil[k] == 0) {
// if j is owned atom, store it, since j is beyond i in linked list
// if j is ghost, only store if j coords are "above and to the "right" of i
if (j >= nlocal) {
if (x[j][2] < ztmp) continue;
if (x[j][2] == ztmp) {
if (x[j][1] < ytmp) continue;
if (x[j][1] == ytmp && x[j][0] < xtmp) continue;
}
}
}
}
jtype = type[j];
if (exclude && exclusion(i,j,itype,jtype,mask,molecule)) continue;
delx = xtmp - x[j][0];
dely = ytmp - x[j][1];
delz = ztmp - x[j][2];
rsq = delx*delx + dely*dely + delz*delz;
if (rsq <= cutneighsq[itype][jtype]) neighptr[n++] = j;
}
}
ilist[inum++] = i;
firstneigh[i] = neighptr;
numneigh[i] = n;
ipage->vgot(n);
if (ipage->status())
error->one(FLERR,"Neighbor list overflow, boost neigh_modify one");
}
list->inum = inum;
if (!HALF) list->gnum = 0;
}
namespace LAMMPS_NS {
template class NPairBinAtomonly<0,1,0>;
template class NPairBinAtomonly<1,1,0>;
}