Files
lammps/src/nstencil_multi_old.cpp
2023-12-21 14:25:31 -05:00

92 lines
3.1 KiB
C++

/* ----------------------------------------------------------------------
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 "nstencil_multi_old.h"
#include "atom.h"
using namespace LAMMPS_NS;
/* ---------------------------------------------------------------------- */
template<int HALF, int DIM_3D, int TRI>
NStencilMultiOld<HALF, DIM_3D, TRI>::NStencilMultiOld(LAMMPS *lmp) : NStencil(lmp) {}
/* ----------------------------------------------------------------------
create stencil based on bin geometry and cutoff
------------------------------------------------------------------------- */
template<int HALF, int DIM_3D, int TRI>
void NStencilMultiOld<HALF, DIM_3D, TRI>::create()
{
int i, j, k, n, itype;
double rsq, typesq;
int *s;
double *distsq;
int ntypes = atom->ntypes;
// For half stencils, only the upper plane is needed
// for triclinic, need to use full stencil in all dims
// not a half stencil in y
// b/c transforming orthog -> lambda -> orthog for ghost atoms
// with an added PBC offset can shift both coords by epsilon
// thus for an I/J owned/ghost pair, the xy coords
// and bin assignments can be different on I proc vs J proc
int sy_min = sy;
int sz_min = sz;
if ((!TRI) && HALF && (!DIM_3D)) sy_min = 0;
if ((!TRI) && HALF && DIM_3D) sz_min = 0;
for (itype = 1; itype <= ntypes; itype++) {
typesq = cuttypesq[itype];
s = stencil_multi_old[itype];
distsq = distsq_multi_old[itype];
n = 0;
// Half and ortho stencils include central bin first
// This preserves the historical order of the neighbor list
// as the old npair classes used to separately parse the central bin first
if (HALF && (!TRI)) s[n++] = 0;
for (k = -sz_min; k <= sz; k++) {
for (j = -sy_min; j <= sy; j++) {
for (i = -sx; i <= sx; i++) {
// Now only include "upper right" bins for half and ortho stencils
if (HALF && (!DIM_3D) && (!TRI))
if (j <= 0 && (j != 0 || i <= 0)) continue;
if (HALF && DIM_3D && (!TRI))
if (k <= 0 && j <= 0 && (j != 0 || i <= 0)) continue;
rsq = bin_distance(i, j, k);
if (rsq < typesq) {
distsq[n] = rsq;
s[n++] = k * mbiny * mbinx + j * mbinx + i;
}
}
}
}
nstencil_multi_old[itype] = n;
}
}
namespace LAMMPS_NS {
template class NStencilMultiOld<0,0,0>;
template class NStencilMultiOld<0,1,0>;
template class NStencilMultiOld<1,0,0>;
template class NStencilMultiOld<1,0,1>;
template class NStencilMultiOld<1,1,0>;
template class NStencilMultiOld<1,1,1>;
}