Page Menu
Home
c4science
Search
Configure Global Search
Log In
Files
F91350394
displace_atoms.cpp
No One
Temporary
Actions
Download File
Edit File
Delete File
View Transforms
Subscribe
Mute Notifications
Award Token
Subscribers
None
File Metadata
Details
File Info
Storage
Attached
Created
Sun, Nov 10, 05:57
Size
5 KB
Mime Type
text/x-c
Expires
Tue, Nov 12, 05:57 (2 d)
Engine
blob
Format
Raw Data
Handle
22209813
Attached To
rLAMMPS lammps
displace_atoms.cpp
View Options
/* ----------------------------------------------------------------------
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 "mpi.h"
#include "stdlib.h"
#include "string.h"
#include "displace_atoms.h"
#include "atom.h"
#include "domain.h"
#include "lattice.h"
#include "comm.h"
#include "group.h"
#include "error.h"
using namespace LAMMPS_NS;
#define MOVE 1
#define RAMP 2
#define MIN(a,b) ((a) < (b) ? (a) : (b))
#define MAX(a,b) ((a) > (b) ? (a) : (b))
/* ---------------------------------------------------------------------- */
DisplaceAtoms::DisplaceAtoms(LAMMPS *lmp) : Pointers(lmp) {}
/* ---------------------------------------------------------------------- */
void DisplaceAtoms::command(int narg, char **arg)
{
if (domain->box_exist == 0)
error->all("Displace_atoms command before simulation box is defined");
if (narg < 2) error->all("Illegal displace_atoms command");
// init entire system since comm->exchange is done
// comm::init needs neighbor::init needs pair::init needs kspace::init, etc
if (comm->me == 0 && screen)
fprintf(screen,"System init for displace_atoms ...\n");
lmp->init();
if (comm->me == 0 && screen) fprintf(screen,"Displacing atoms ...\n");
// group and style
int igroup = group->find(arg[0]);
if (igroup == -1) error->all("Could not find displace_atoms group ID");
int groupbit = group->bitmask[igroup];
int style;
if (strcmp(arg[1],"move") == 0) style = MOVE;
else if (strcmp(arg[1],"ramp") == 0) style = RAMP;
else error->all("Illegal displace_atoms command");
// set option defaults
scaleflag = 1;
// read options from end of input line
if (style == MOVE) options(narg-5,&arg[5]);
else if (style == RAMP) options(narg-8,&arg[8]);
// setup scaling
if (scaleflag && domain->lattice == NULL)
error->all("Use of displace_atoms with undefined lattice");
double xscale,yscale,zscale;
if (scaleflag) {
xscale = domain->lattice->xlattice;
yscale = domain->lattice->ylattice;
zscale = domain->lattice->zlattice;
}
else xscale = yscale = zscale = 1.0;
// move atoms directly by specified 3-vector distance
if (style == MOVE) {
double delx,dely,delz;
delx = xscale*atof(arg[2]);
dely = yscale*atof(arg[3]);
delz = zscale*atof(arg[4]);
double **x = atom->x;
int *mask = atom->mask;
int nlocal = atom->nlocal;
for (int i = 0; i < nlocal; i++) {
if (mask[i] & groupbit) {
x[i][0] += delx;
x[i][1] += dely;
x[i][2] += delz;
}
}
// move atoms in ramped fashion
} else if (style == RAMP) {
int d_dim;
if (strcmp(arg[2],"x") == 0) d_dim = 0;
else if (strcmp(arg[2],"y") == 0) d_dim = 1;
else if (strcmp(arg[2],"z") == 0) d_dim = 2;
else error->all("Illegal displace_atoms ramp command");
double d_lo,d_hi;
if (d_dim == 0) {
d_lo = xscale*atof(arg[3]);
d_hi = xscale*atof(arg[4]);
} else if (d_dim == 1) {
d_lo = yscale*atof(arg[3]);
d_hi = yscale*atof(arg[4]);
} else if (d_dim == 2) {
d_lo = zscale*atof(arg[3]);
d_hi = zscale*atof(arg[4]);
}
int coord_dim;
if (strcmp(arg[5],"x") == 0) coord_dim = 0;
else if (strcmp(arg[5],"y") == 0) coord_dim = 1;
else if (strcmp(arg[5],"z") == 0) coord_dim = 2;
else error->all("Illegal velocity ramp command");
double coord_lo,coord_hi;
if (coord_dim == 0) {
coord_lo = xscale*atof(arg[6]);
coord_hi = xscale*atof(arg[7]);
} else if (coord_dim == 1) {
coord_lo = yscale*atof(arg[6]);
coord_hi = yscale*atof(arg[7]);
} else if (coord_dim == 2) {
coord_lo = zscale*atof(arg[6]);
coord_hi = zscale*atof(arg[7]);
}
double **x = atom->x;
int *mask = atom->mask;
int nlocal = atom->nlocal;
double fraction,dramp;
for (int i = 0; i < nlocal; i++) {
if (mask[i] & groupbit) {
fraction = (x[i][coord_dim] - coord_lo) / (coord_hi - coord_lo);
fraction = MAX(fraction,0.0);
fraction = MIN(fraction,1.0);
dramp = d_lo + fraction*(d_hi - d_lo);
x[i][d_dim] += dramp;
}
}
}
// move atoms to new processors
// enforce PBC before in case atoms are outside box
domain->pbc();
domain->reset_box();
comm->setup();
comm->exchange();
// check if any atoms were lost
double natoms;
double rlocal = atom->nlocal;
MPI_Allreduce(&rlocal,&natoms,1,MPI_DOUBLE,MPI_SUM,world);
if (natoms != atom->natoms) {
char str[128];
sprintf(str,"Lost atoms via displacement: original %.15g current %.15g",
atom->natoms,natoms);
error->all(str);
}
}
/* ----------------------------------------------------------------------
parse optional parameters at end of displace_atoms input line
------------------------------------------------------------------------- */
void DisplaceAtoms::options(int narg, char **arg)
{
if (narg < 0) error->all("Illegal displace_atoms command");
int iarg = 0;
while (iarg < narg) {
if (strcmp(arg[iarg],"units") == 0) {
if (iarg+2 > narg) error->all("Illegal displace_atoms command");
if (strcmp(arg[iarg+1],"box") == 0) scaleflag = 0;
else if (strcmp(arg[iarg+1],"lattice") == 0) scaleflag = 1;
else error->all("Illegal displace_atoms command");
iarg += 2;
} else error->all("Illegal displace_atoms command");
}
}
Event Timeline
Log In to Comment