Page Menu
Home
c4science
Search
Configure Global Search
Log In
Files
F78649986
fix_rigid.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
Thu, Aug 22, 04:35
Size
73 KB
Mime Type
text/x-c
Expires
Sat, Aug 24, 04:35 (2 d)
Engine
blob
Format
Raw Data
Handle
20080871
Attached To
rLAMMPS lammps
fix_rigid.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 "math.h"
#include "stdio.h"
#include "stdlib.h"
#include "string.h"
#include "fix_rigid.h"
#include "math_extra.h"
#include "atom.h"
#include "atom_vec_ellipsoid.h"
#include "atom_vec_line.h"
#include "atom_vec_tri.h"
#include "domain.h"
#include "update.h"
#include "respa.h"
#include "modify.h"
#include "group.h"
#include "comm.h"
#include "random_mars.h"
#include "force.h"
#include "output.h"
#include "math_const.h"
#include "memory.h"
#include "error.h"
using namespace LAMMPS_NS;
using namespace FixConst;
using namespace MathConst;
enum{SINGLE,MOLECULE,GROUP};
enum{NONE,XYZ,XY,YZ,XZ};
enum{ISO,ANISO,TRICLINIC};
#define MAXLINE 256
#define CHUNK 1024
#define ATTRIBUTE_PERBODY 11
#define TOLERANCE 1.0e-6
#define EPSILON 1.0e-7
#define SINERTIA 0.4 // moment of inertia prefactor for sphere
#define EINERTIA 0.4 // moment of inertia prefactor for ellipsoid
#define LINERTIA (1.0/12.0) // moment of inertia prefactor for line segment
/* ---------------------------------------------------------------------- */
FixRigid::FixRigid(LAMMPS *lmp, int narg, char **arg) :
Fix(lmp, narg, arg)
{
int i,ibody;
scalar_flag = 1;
extscalar = 0;
time_integrate = 1;
rigid_flag = 1;
virial_flag = 1;
create_attribute = 1;
MPI_Comm_rank(world,&me);
MPI_Comm_size(world,&nprocs);
// perform initial allocation of atom-based arrays
// register with Atom class
extended = orientflag = dorientflag = 0;
body = NULL;
displace = NULL;
eflags = NULL;
orient = NULL;
dorient = NULL;
grow_arrays(atom->nmax);
atom->add_callback(0);
// parse args for rigid body specification
// set nbody and body[i] for each atom
if (narg < 4) error->all(FLERR,"Illegal fix rigid command");
int iarg;
mol2body = NULL;
// single rigid body
// nbody = 1
// all atoms in fix group are part of body
if (strcmp(arg[3],"single") == 0) {
rstyle = SINGLE;
iarg = 4;
nbody = 1;
int *mask = atom->mask;
int nlocal = atom->nlocal;
for (i = 0; i < nlocal; i++) {
body[i] = -1;
if (mask[i] & groupbit) body[i] = 0;
}
// each molecule in fix group is a rigid body
// maxmol = largest molecule #
// ncount = # of atoms in each molecule (have to sum across procs)
// nbody = # of non-zero ncount values
// use nall as incremented ptr to set body[] values for each atom
} else if (strcmp(arg[3],"molecule") == 0) {
rstyle = MOLECULE;
iarg = 4;
if (atom->molecule_flag == 0)
error->all(FLERR,"Fix rigid molecule requires atom attribute molecule");
int *mask = atom->mask;
int *molecule = atom->molecule;
int nlocal = atom->nlocal;
maxmol = -1;
for (i = 0; i < nlocal; i++)
if (mask[i] & groupbit) maxmol = MAX(maxmol,molecule[i]);
int itmp;
MPI_Allreduce(&maxmol,&itmp,1,MPI_INT,MPI_MAX,world);
maxmol = itmp;
int *ncount;
memory->create(ncount,maxmol+1,"rigid:ncount");
for (i = 0; i <= maxmol; i++) ncount[i] = 0;
for (i = 0; i < nlocal; i++)
if (mask[i] & groupbit) ncount[molecule[i]]++;
memory->create(mol2body,maxmol+1,"rigid:ncount");
MPI_Allreduce(ncount,mol2body,maxmol+1,MPI_INT,MPI_SUM,world);
nbody = 0;
for (i = 0; i <= maxmol; i++)
if (mol2body[i]) mol2body[i] = nbody++;
else mol2body[i] = -1;
for (i = 0; i < nlocal; i++) {
body[i] = -1;
if (mask[i] & groupbit) body[i] = mol2body[molecule[i]];
}
memory->destroy(ncount);
// each listed group is a rigid body
// check if all listed groups exist
// an atom must belong to fix group and listed group to be in rigid body
// error if atom belongs to more than 1 rigid body
} else if (strcmp(arg[3],"group") == 0) {
if (narg < 5) error->all(FLERR,"Illegal fix rigid command");
rstyle = GROUP;
nbody = atoi(arg[4]);
if (nbody <= 0) error->all(FLERR,"Illegal fix rigid command");
if (narg < 5+nbody) error->all(FLERR,"Illegal fix rigid command");
iarg = 5+nbody;
int *igroups = new int[nbody];
for (ibody = 0; ibody < nbody; ibody++) {
igroups[ibody] = group->find(arg[5+ibody]);
if (igroups[ibody] == -1)
error->all(FLERR,"Could not find fix rigid group ID");
}
int *mask = atom->mask;
int nlocal = atom->nlocal;
int flag = 0;
for (i = 0; i < nlocal; i++) {
body[i] = -1;
if (mask[i] & groupbit)
for (ibody = 0; ibody < nbody; ibody++)
if (mask[i] & group->bitmask[igroups[ibody]]) {
if (body[i] >= 0) flag = 1;
body[i] = ibody;
}
}
int flagall;
MPI_Allreduce(&flag,&flagall,1,MPI_INT,MPI_SUM,world);
if (flagall)
error->all(FLERR,"One or more atoms belong to multiple rigid bodies");
delete [] igroups;
} else error->all(FLERR,"Illegal fix rigid command");
// error check on nbody
if (nbody == 0) error->all(FLERR,"No rigid bodies defined");
// create all nbody-length arrays
memory->create(nrigid,nbody,"rigid:nrigid");
memory->create(masstotal,nbody,"rigid:masstotal");
memory->create(xcm,nbody,3,"rigid:xcm");
memory->create(vcm,nbody,3,"rigid:vcm");
memory->create(fcm,nbody,3,"rigid:fcm");
memory->create(inertia,nbody,3,"rigid:inertia");
memory->create(ex_space,nbody,3,"rigid:ex_space");
memory->create(ey_space,nbody,3,"rigid:ey_space");
memory->create(ez_space,nbody,3,"rigid:ez_space");
memory->create(angmom,nbody,3,"rigid:angmom");
memory->create(omega,nbody,3,"rigid:omega");
memory->create(torque,nbody,3,"rigid:torque");
memory->create(quat,nbody,4,"rigid:quat");
memory->create(imagebody,nbody,"rigid:imagebody");
memory->create(fflag,nbody,3,"rigid:fflag");
memory->create(tflag,nbody,3,"rigid:tflag");
memory->create(langextra,nbody,6,"rigid:langextra");
memory->create(sum,nbody,6,"rigid:sum");
memory->create(all,nbody,6,"rigid:all");
memory->create(remapflag,nbody,4,"rigid:remapflag");
// initialize force/torque flags to default = 1.0
// for 2d: fz, tx, ty = 0.0
array_flag = 1;
size_array_rows = nbody;
size_array_cols = 15;
global_freq = 1;
extarray = 0;
for (i = 0; i < nbody; i++) {
fflag[i][0] = fflag[i][1] = fflag[i][2] = 1.0;
tflag[i][0] = tflag[i][1] = tflag[i][2] = 1.0;
if (domain->dimension == 2) fflag[i][2] = tflag[i][0] = tflag[i][1] = 0.0;
}
// parse optional args
int seed;
langflag = 0;
tstat_flag = 0;
pstat_flag = 0;
allremap = 1;
id_dilate = NULL;
t_chain = 10;
t_iter = 1;
t_order = 3;
p_chain = 10;
infile = NULL;
pcouple = NONE;
pstyle = ANISO;
dimension = domain->dimension;
for (int i = 0; i < 3; i++) {
p_start[i] = p_stop[i] = p_period[i] = 0.0;
p_flag[i] = 0;
}
while (iarg < narg) {
if (strcmp(arg[iarg],"force") == 0) {
if (iarg+5 > narg) error->all(FLERR,"Illegal fix rigid command");
int mlo,mhi;
force->bounds(arg[iarg+1],nbody,mlo,mhi);
double xflag,yflag,zflag;
if (strcmp(arg[iarg+2],"off") == 0) xflag = 0.0;
else if (strcmp(arg[iarg+2],"on") == 0) xflag = 1.0;
else error->all(FLERR,"Illegal fix rigid command");
if (strcmp(arg[iarg+3],"off") == 0) yflag = 0.0;
else if (strcmp(arg[iarg+3],"on") == 0) yflag = 1.0;
else error->all(FLERR,"Illegal fix rigid command");
if (strcmp(arg[iarg+4],"off") == 0) zflag = 0.0;
else if (strcmp(arg[iarg+4],"on") == 0) zflag = 1.0;
else error->all(FLERR,"Illegal fix rigid command");
if (domain->dimension == 2 && zflag == 1.0)
error->all(FLERR,"Fix rigid z force cannot be on for 2d simulation");
int count = 0;
for (int m = mlo; m <= mhi; m++) {
fflag[m-1][0] = xflag;
fflag[m-1][1] = yflag;
fflag[m-1][2] = zflag;
count++;
}
if (count == 0) error->all(FLERR,"Illegal fix rigid command");
iarg += 5;
} else if (strcmp(arg[iarg],"torque") == 0) {
if (iarg+5 > narg) error->all(FLERR,"Illegal fix rigid command");
int mlo,mhi;
force->bounds(arg[iarg+1],nbody,mlo,mhi);
double xflag,yflag,zflag;
if (strcmp(arg[iarg+2],"off") == 0) xflag = 0.0;
else if (strcmp(arg[iarg+2],"on") == 0) xflag = 1.0;
else error->all(FLERR,"Illegal fix rigid command");
if (strcmp(arg[iarg+3],"off") == 0) yflag = 0.0;
else if (strcmp(arg[iarg+3],"on") == 0) yflag = 1.0;
else error->all(FLERR,"Illegal fix rigid command");
if (strcmp(arg[iarg+4],"off") == 0) zflag = 0.0;
else if (strcmp(arg[iarg+4],"on") == 0) zflag = 1.0;
else error->all(FLERR,"Illegal fix rigid command");
if (domain->dimension == 2 && (xflag == 1.0 || yflag == 1.0))
error->all(FLERR,"Fix rigid xy torque cannot be on for 2d simulation");
int count = 0;
for (int m = mlo; m <= mhi; m++) {
tflag[m-1][0] = xflag;
tflag[m-1][1] = yflag;
tflag[m-1][2] = zflag;
count++;
}
if (count == 0) error->all(FLERR,"Illegal fix rigid command");
iarg += 5;
} else if (strcmp(arg[iarg],"langevin") == 0) {
if (iarg+5 > narg) error->all(FLERR,"Illegal fix rigid command");
if (strcmp(style,"rigid") != 0 && strcmp(style,"rigid/nve") != 0)
error->all(FLERR,"Illegal fix rigid command");
langflag = 1;
t_start = atof(arg[iarg+1]);
t_stop = atof(arg[iarg+2]);
t_period = atof(arg[iarg+3]);
seed = atoi(arg[iarg+4]);
if (t_period <= 0.0)
error->all(FLERR,"Fix rigid langevin period must be > 0.0");
if (seed <= 0) error->all(FLERR,"Illegal fix rigid command");
iarg += 5;
} else if (strcmp(arg[iarg],"temp") == 0) {
if (iarg+4 > narg) error->all(FLERR,"Illegal fix rigid command");
if (strcmp(style,"rigid/nvt") != 0 && strcmp(style,"rigid/npt") != 0)
error->all(FLERR,"Illegal fix rigid command");
tstat_flag = 1;
t_start = atof(arg[iarg+1]);
t_stop = atof(arg[iarg+2]);
t_period = atof(arg[iarg+3]);
iarg += 4;
} else if (strcmp(arg[iarg],"iso") == 0) {
if (iarg+4 > narg) error->all(FLERR,"Illegal fix rigid command");
if (strcmp(style,"rigid/npt") != 0 && strcmp(style,"rigid/nph") != 0)
error->all(FLERR,"Illegal fix rigid command");
pcouple = XYZ;
p_start[0] = p_start[1] = p_start[2] = atof(arg[iarg+1]);
p_stop[0] = p_stop[1] = p_stop[2] = atof(arg[iarg+2]);
p_period[0] = p_period[1] = p_period[2] = atof(arg[iarg+3]);
p_flag[0] = p_flag[1] = p_flag[2] = 1;
if (dimension == 2) {
p_start[2] = p_stop[2] = p_period[2] = 0.0;
p_flag[2] = 0;
}
iarg += 4;
} else if (strcmp(arg[iarg],"aniso") == 0) {
if (iarg+4 > narg) error->all(FLERR,"Illegal fix rigid command");
if (strcmp(style,"rigid/npt") != 0 && strcmp(style,"rigid/nph") != 0)
error->all(FLERR,"Illegal fix rigid command");
p_start[0] = p_start[1] = p_start[2] = atof(arg[iarg+1]);
p_stop[0] = p_stop[1] = p_stop[2] = atof(arg[iarg+2]);
p_period[0] = p_period[1] = p_period[2] = atof(arg[iarg+3]);
p_flag[0] = p_flag[1] = p_flag[2] = 1;
if (dimension == 2) {
p_start[2] = p_stop[2] = p_period[2] = 0.0;
p_flag[2] = 0;
}
iarg += 4;
} else if (strcmp(arg[iarg],"x") == 0) {
if (iarg+4 > narg) error->all(FLERR,"Illegal fix rigid command");
p_start[0] = atof(arg[iarg+1]);
p_stop[0] = atof(arg[iarg+2]);
p_period[0] = atof(arg[iarg+3]);
p_flag[0] = 1;
iarg += 4;
} else if (strcmp(arg[iarg],"y") == 0) {
if (iarg+4 > narg) error->all(FLERR,"Illegal fix rigid command");
p_start[1] = atof(arg[iarg+1]);
p_stop[1] = atof(arg[iarg+2]);
p_period[1] = atof(arg[iarg+3]);
p_flag[1] = 1;
iarg += 4;
} else if (strcmp(arg[iarg],"z") == 0) {
if (iarg+4 > narg) error->all(FLERR,"Illegal fix rigid command");
p_start[2] = atof(arg[iarg+1]);
p_stop[2] = atof(arg[iarg+2]);
p_period[2] = atof(arg[iarg+3]);
p_flag[2] = 1;
iarg += 4;
} else if (strcmp(arg[iarg],"couple") == 0) {
if (iarg+2 > narg) error->all(FLERR,"Illegal fix rigid command");
if (strcmp(arg[iarg+1],"xyz") == 0) pcouple = XYZ;
else if (strcmp(arg[iarg+1],"xy") == 0) pcouple = XY;
else if (strcmp(arg[iarg+1],"yz") == 0) pcouple = YZ;
else if (strcmp(arg[iarg+1],"xz") == 0) pcouple = XZ;
else if (strcmp(arg[iarg+1],"none") == 0) pcouple = NONE;
else error->all(FLERR,"Illegal fix rigid command");
iarg += 2;
} else if (strcmp(arg[iarg],"dilate") == 0) {
if (iarg+2 > narg)
error->all(FLERR,"Illegal fix rigid nvt/npt/nph command");
if (strcmp(arg[iarg+1],"all") == 0) allremap = 1;
else {
allremap = 0;
delete [] id_dilate;
int n = strlen(arg[iarg+1]) + 1;
id_dilate = new char[n];
strcpy(id_dilate,arg[iarg+1]);
int idilate = group->find(id_dilate);
if (idilate == -1)
error->all(FLERR,
"Fix rigid nvt/npt/nph dilate group ID does not exist");
}
iarg += 2;
} else if (strcmp(arg[iarg],"tparam") == 0) {
if (iarg+4 > narg) error->all(FLERR,"Illegal fix rigid command");
if (strcmp(style,"rigid/nvt") != 0 && strcmp(style,"rigid/npt") != 0)
error->all(FLERR,"Illegal fix rigid command");
t_chain = atoi(arg[iarg+1]);
t_iter = atoi(arg[iarg+2]);
t_order = atoi(arg[iarg+3]);
iarg += 4;
} else if (strcmp(arg[iarg],"pchain") == 0) {
if (iarg+2 > narg) error->all(FLERR,"Illegal fix rigid command");
if (strcmp(style,"rigid/npt") != 0 && strcmp(style,"rigid/nph") != 0)
error->all(FLERR,"Illegal fix rigid command");
p_chain = atoi(arg[iarg+1]);
iarg += 2;
} else if (strcmp(arg[iarg],"infile") == 0) {
if (iarg+2 > narg) error->all(FLERR,"Illegal fix rigid command");
delete [] infile;
int n = strlen(arg[iarg+1]) + 1;
infile = new char[n];
strcpy(infile,arg[iarg+1]);
iarg += 2;
} else error->all(FLERR,"Illegal fix rigid command");
}
// set pstat_flag
pstat_flag = 0;
for (int i = 0; i < 3; i++)
if (p_flag[i]) pstat_flag = 1;
if (pcouple == XYZ || (dimension == 2 && pcouple == XY)) pstyle = ISO;
else pstyle = ANISO;
// initialize Marsaglia RNG with processor-unique seed
if (langflag) random = new RanMars(lmp,seed + me);
else random = NULL;
// initialize vector output quantities in case accessed before run
for (i = 0; i < nbody; i++) {
xcm[i][0] = xcm[i][1] = xcm[i][2] = 0.0;
vcm[i][0] = vcm[i][1] = vcm[i][2] = 0.0;
fcm[i][0] = fcm[i][1] = fcm[i][2] = 0.0;
torque[i][0] = torque[i][1] = torque[i][2] = 0.0;
}
// nrigid[n] = # of atoms in Nth rigid body
// error if one or zero atoms
int *ncount = new int[nbody];
for (ibody = 0; ibody < nbody; ibody++) ncount[ibody] = 0;
int nlocal = atom->nlocal;
for (i = 0; i < nlocal; i++)
if (body[i] >= 0) ncount[body[i]]++;
MPI_Allreduce(ncount,nrigid,nbody,MPI_INT,MPI_SUM,world);
delete [] ncount;
for (ibody = 0; ibody < nbody; ibody++)
if (nrigid[ibody] <= 1) error->all(FLERR,"One or zero atoms in rigid body");
// bitmasks for properties of extended particles
POINT = 1;
SPHERE = 2;
ELLIPSOID = 4;
LINE = 8;
TRIANGLE = 16;
DIPOLE = 32;
OMEGA = 64;
ANGMOM = 128;
TORQUE = 256;
MINUSPI = -MY_PI;
TWOPI = 2.0*MY_PI;
// print statistics
int nsum = 0;
for (ibody = 0; ibody < nbody; ibody++) nsum += nrigid[ibody];
if (me == 0) {
if (screen) fprintf(screen,"%d rigid bodies with %d atoms\n",nbody,nsum);
if (logfile) fprintf(logfile,"%d rigid bodies with %d atoms\n",nbody,nsum);
}
// firstflag = 1 triggers one-time initialization of rigid body attributes
firstflag = 1;
}
/* ---------------------------------------------------------------------- */
FixRigid::~FixRigid()
{
// unregister callbacks to this fix from Atom class
atom->delete_callback(id,0);
delete random;
delete [] infile;
memory->destroy(mol2body);
// delete locally stored arrays
memory->destroy(body);
memory->destroy(displace);
memory->destroy(eflags);
memory->destroy(orient);
memory->destroy(dorient);
// delete nbody-length arrays
memory->destroy(nrigid);
memory->destroy(masstotal);
memory->destroy(xcm);
memory->destroy(vcm);
memory->destroy(fcm);
memory->destroy(inertia);
memory->destroy(ex_space);
memory->destroy(ey_space);
memory->destroy(ez_space);
memory->destroy(angmom);
memory->destroy(omega);
memory->destroy(torque);
memory->destroy(quat);
memory->destroy(imagebody);
memory->destroy(fflag);
memory->destroy(tflag);
memory->destroy(langextra);
memory->destroy(sum);
memory->destroy(all);
memory->destroy(remapflag);
}
/* ---------------------------------------------------------------------- */
int FixRigid::setmask()
{
int mask = 0;
mask |= INITIAL_INTEGRATE;
mask |= FINAL_INTEGRATE;
if (langflag) mask |= POST_FORCE;
mask |= PRE_NEIGHBOR;
mask |= INITIAL_INTEGRATE_RESPA;
mask |= FINAL_INTEGRATE_RESPA;
return mask;
}
/* ---------------------------------------------------------------------- */
void FixRigid::init()
{
int i,ibody;
triclinic = domain->triclinic;
// atom style pointers to particles that store extra info
avec_ellipsoid = (AtomVecEllipsoid *) atom->style_match("ellipsoid");
avec_line = (AtomVecLine *) atom->style_match("line");
avec_tri = (AtomVecTri *) atom->style_match("tri");
// warn if more than one rigid fix
int count = 0;
for (i = 0; i < modify->nfix; i++)
if (strcmp(modify->fix[i]->style,"rigid") == 0) count++;
if (count > 1 && me == 0) error->warning(FLERR,"More than one fix rigid");
// error if npt,nph fix comes before rigid fix
for (i = 0; i < modify->nfix; i++) {
if (strcmp(modify->fix[i]->style,"npt") == 0) break;
if (strcmp(modify->fix[i]->style,"nph") == 0) break;
}
if (i < modify->nfix) {
for (int j = i; j < modify->nfix; j++)
if (strcmp(modify->fix[j]->style,"rigid") == 0)
error->all(FLERR,"Rigid fix must come before NPT/NPH fix");
}
// timestep info
dtv = update->dt;
dtf = 0.5 * update->dt * force->ftm2v;
dtq = 0.5 * update->dt;
if (strstr(update->integrate_style,"respa"))
step_respa = ((Respa *) update->integrate)->step;
// one-time initialization of rigid body attributes
// extended flags, masstotal, COM, inertia tensor
if (firstflag) setup_bodies();
firstflag = 0;
// temperature scale factor
double ndof = 0.0;
for (ibody = 0; ibody < nbody; ibody++) {
ndof += fflag[ibody][0] + fflag[ibody][1] + fflag[ibody][2];
ndof += tflag[ibody][0] + tflag[ibody][1] + tflag[ibody][2];
}
if (ndof > 0.0) tfactor = force->mvv2e / (ndof * force->boltz);
else tfactor = 0.0;
}
/* ---------------------------------------------------------------------- */
void FixRigid::setup(int vflag)
{
int i,n,ibody;
double massone,radone;
// vcm = velocity of center-of-mass of each rigid body
// fcm = force on center-of-mass of each rigid body
double **v = atom->v;
double **f = atom->f;
double *rmass = atom->rmass;
double *mass = atom->mass;
int *type = atom->type;
int nlocal = atom->nlocal;
for (ibody = 0; ibody < nbody; ibody++)
for (i = 0; i < 6; i++) sum[ibody][i] = 0.0;
for (i = 0; i < nlocal; i++) {
if (body[i] < 0) continue;
ibody = body[i];
if (rmass) massone = rmass[i];
else massone = mass[type[i]];
sum[ibody][0] += v[i][0] * massone;
sum[ibody][1] += v[i][1] * massone;
sum[ibody][2] += v[i][2] * massone;
sum[ibody][3] += f[i][0];
sum[ibody][4] += f[i][1];
sum[ibody][5] += f[i][2];
}
MPI_Allreduce(sum[0],all[0],6*nbody,MPI_DOUBLE,MPI_SUM,world);
for (ibody = 0; ibody < nbody; ibody++) {
vcm[ibody][0] = all[ibody][0]/masstotal[ibody];
vcm[ibody][1] = all[ibody][1]/masstotal[ibody];
vcm[ibody][2] = all[ibody][2]/masstotal[ibody];
fcm[ibody][0] = all[ibody][3];
fcm[ibody][1] = all[ibody][4];
fcm[ibody][2] = all[ibody][5];
}
// angmom = angular momentum of each rigid body
// torque = torque on each rigid body
tagint *image = atom->image;
double **x = atom->x;
double dx,dy,dz;
double unwrap[3];
for (ibody = 0; ibody < nbody; ibody++)
for (i = 0; i < 6; i++) sum[ibody][i] = 0.0;
for (i = 0; i < nlocal; i++) {
if (body[i] < 0) continue;
ibody = body[i];
domain->unmap(x[i],image[i],unwrap);
dx = unwrap[0] - xcm[ibody][0];
dy = unwrap[1] - xcm[ibody][1];
dz = unwrap[2] - xcm[ibody][2];
if (rmass) massone = rmass[i];
else massone = mass[type[i]];
sum[ibody][0] += dy * massone*v[i][2] - dz * massone*v[i][1];
sum[ibody][1] += dz * massone*v[i][0] - dx * massone*v[i][2];
sum[ibody][2] += dx * massone*v[i][1] - dy * massone*v[i][0];
sum[ibody][3] += dy * f[i][2] - dz * f[i][1];
sum[ibody][4] += dz * f[i][0] - dx * f[i][2];
sum[ibody][5] += dx * f[i][1] - dy * f[i][0];
}
// extended particles add their rotation/torque to angmom/torque of body
if (extended) {
AtomVecLine::Bonus *lbonus;
if (avec_line) lbonus = avec_line->bonus;
double **omega_one = atom->omega;
double **angmom_one = atom->angmom;
double **torque_one = atom->torque;
double *radius = atom->radius;
int *line = atom->line;
for (i = 0; i < nlocal; i++) {
if (body[i] < 0) continue;
ibody = body[i];
if (eflags[i] & OMEGA) {
if (eflags[i] & SPHERE) {
radone = radius[i];
sum[ibody][0] += SINERTIA*rmass[i] * radone*radone * omega_one[i][0];
sum[ibody][1] += SINERTIA*rmass[i] * radone*radone * omega_one[i][1];
sum[ibody][2] += SINERTIA*rmass[i] * radone*radone * omega_one[i][2];
} else if (eflags[i] & LINE) {
radone = lbonus[line[i]].length;
sum[ibody][2] += LINERTIA*rmass[i] * radone*radone * omega_one[i][2];
}
}
if (eflags[i] & ANGMOM) {
sum[ibody][0] += angmom_one[i][0];
sum[ibody][1] += angmom_one[i][1];
sum[ibody][2] += angmom_one[i][2];
}
if (eflags[i] & TORQUE) {
sum[ibody][3] += torque_one[i][0];
sum[ibody][4] += torque_one[i][1];
sum[ibody][5] += torque_one[i][2];
}
}
}
MPI_Allreduce(sum[0],all[0],6*nbody,MPI_DOUBLE,MPI_SUM,world);
for (ibody = 0; ibody < nbody; ibody++) {
angmom[ibody][0] = all[ibody][0];
angmom[ibody][1] = all[ibody][1];
angmom[ibody][2] = all[ibody][2];
torque[ibody][0] = all[ibody][3];
torque[ibody][1] = all[ibody][4];
torque[ibody][2] = all[ibody][5];
}
// zero langextra in case Langevin thermostat not used
// no point to calling post_force() here since langextra
// is only added to fcm/torque in final_integrate()
for (ibody = 0; ibody < nbody; ibody++)
for (i = 0; i < 6; i++) langextra[ibody][i] = 0.0;
// virial setup before call to set_v
if (vflag) v_setup(vflag);
else evflag = 0;
// set velocities from angmom & omega
for (ibody = 0; ibody < nbody; ibody++)
MathExtra::angmom_to_omega(angmom[ibody],ex_space[ibody],ey_space[ibody],
ez_space[ibody],inertia[ibody],omega[ibody]);
set_v();
// guesstimate virial as 2x the set_v contribution
if (vflag_global)
for (n = 0; n < 6; n++) virial[n] *= 2.0;
if (vflag_atom) {
for (i = 0; i < nlocal; i++)
for (n = 0; n < 6; n++)
vatom[i][n] *= 2.0;
}
}
/* ---------------------------------------------------------------------- */
void FixRigid::initial_integrate(int vflag)
{
double dtfm;
for (int ibody = 0; ibody < nbody; ibody++) {
// update vcm by 1/2 step
dtfm = dtf / masstotal[ibody];
vcm[ibody][0] += dtfm * fcm[ibody][0] * fflag[ibody][0];
vcm[ibody][1] += dtfm * fcm[ibody][1] * fflag[ibody][1];
vcm[ibody][2] += dtfm * fcm[ibody][2] * fflag[ibody][2];
// update xcm by full step
xcm[ibody][0] += dtv * vcm[ibody][0];
xcm[ibody][1] += dtv * vcm[ibody][1];
xcm[ibody][2] += dtv * vcm[ibody][2];
// update angular momentum by 1/2 step
angmom[ibody][0] += dtf * torque[ibody][0] * tflag[ibody][0];
angmom[ibody][1] += dtf * torque[ibody][1] * tflag[ibody][1];
angmom[ibody][2] += dtf * torque[ibody][2] * tflag[ibody][2];
// compute omega at 1/2 step from angmom at 1/2 step and current q
// update quaternion a full step via Richardson iteration
// returns new normalized quaternion, also updated omega at 1/2 step
// update ex,ey,ez to reflect new quaternion
MathExtra::angmom_to_omega(angmom[ibody],ex_space[ibody],ey_space[ibody],
ez_space[ibody],inertia[ibody],omega[ibody]);
MathExtra::richardson(quat[ibody],angmom[ibody],omega[ibody],
inertia[ibody],dtq);
MathExtra::q_to_exyz(quat[ibody],
ex_space[ibody],ey_space[ibody],ez_space[ibody]);
}
// virial setup before call to set_xv
if (vflag) v_setup(vflag);
else evflag = 0;
// set coords/orient and velocity/rotation of atoms in rigid bodies
// from quarternion and omega
set_xv();
}
/* ----------------------------------------------------------------------
apply Langevin thermostat to all 6 DOF of rigid bodies
computed by proc 0, broadcast to other procs
unlike fix langevin, this stores extra force in extra arrays,
which are added in when final_integrate() calculates a new fcm/torque
------------------------------------------------------------------------- */
void FixRigid::post_force(int vflag)
{
if (me == 0) {
double gamma1,gamma2;
double delta = update->ntimestep - update->beginstep;
if (delta != 0.0) delta /= update->endstep - update->beginstep;
t_target = t_start + delta * (t_stop-t_start);
double tsqrt = sqrt(t_target);
double boltz = force->boltz;
double dt = update->dt;
double mvv2e = force->mvv2e;
double ftm2v = force->ftm2v;
for (int i = 0; i < nbody; i++) {
gamma1 = -masstotal[i] / t_period / ftm2v;
gamma2 = sqrt(masstotal[i]) * tsqrt *
sqrt(24.0*boltz/t_period/dt/mvv2e) / ftm2v;
langextra[i][0] = gamma1*vcm[i][0] + gamma2*(random->uniform()-0.5);
langextra[i][1] = gamma1*vcm[i][1] + gamma2*(random->uniform()-0.5);
langextra[i][2] = gamma1*vcm[i][2] + gamma2*(random->uniform()-0.5);
gamma1 = -1.0 / t_period / ftm2v;
gamma2 = tsqrt * sqrt(24.0*boltz/t_period/dt/mvv2e) / ftm2v;
langextra[i][3] = inertia[i][0]*gamma1*omega[i][0] +
sqrt(inertia[i][0])*gamma2*(random->uniform()-0.5);
langextra[i][4] = inertia[i][1]*gamma1*omega[i][1] +
sqrt(inertia[i][1])*gamma2*(random->uniform()-0.5);
langextra[i][5] = inertia[i][2]*gamma1*omega[i][2] +
sqrt(inertia[i][2])*gamma2*(random->uniform()-0.5);
}
}
MPI_Bcast(&langextra[0][0],6*nbody,MPI_DOUBLE,0,world);
}
/* ---------------------------------------------------------------------- */
void FixRigid::final_integrate()
{
int i,ibody;
double dtfm,xy,xz,yz;
// sum over atoms to get force and torque on rigid body
tagint *image = atom->image;
double **x = atom->x;
double **f = atom->f;
int nlocal = atom->nlocal;
double dx,dy,dz;
double unwrap[3];
for (ibody = 0; ibody < nbody; ibody++)
for (i = 0; i < 6; i++) sum[ibody][i] = 0.0;
for (i = 0; i < nlocal; i++) {
if (body[i] < 0) continue;
ibody = body[i];
sum[ibody][0] += f[i][0];
sum[ibody][1] += f[i][1];
sum[ibody][2] += f[i][2];
domain->unmap(x[i],image[i],unwrap);
dx = unwrap[0] - xcm[ibody][0];
dy = unwrap[1] - xcm[ibody][1];
dz = unwrap[2] - xcm[ibody][2];
sum[ibody][3] += dy*f[i][2] - dz*f[i][1];
sum[ibody][4] += dz*f[i][0] - dx*f[i][2];
sum[ibody][5] += dx*f[i][1] - dy*f[i][0];
}
// extended particles add their torque to torque of body
if (extended) {
double **torque_one = atom->torque;
for (i = 0; i < nlocal; i++) {
if (body[i] < 0) continue;
ibody = body[i];
if (eflags[i] & TORQUE) {
sum[ibody][3] += torque_one[i][0];
sum[ibody][4] += torque_one[i][1];
sum[ibody][5] += torque_one[i][2];
}
}
}
MPI_Allreduce(sum[0],all[0],6*nbody,MPI_DOUBLE,MPI_SUM,world);
// update vcm and angmom
// include Langevin thermostat forces
// fflag,tflag = 0 for some dimensions in 2d
for (ibody = 0; ibody < nbody; ibody++) {
fcm[ibody][0] = all[ibody][0] + langextra[ibody][0];
fcm[ibody][1] = all[ibody][1] + langextra[ibody][1];
fcm[ibody][2] = all[ibody][2] + langextra[ibody][2];
torque[ibody][0] = all[ibody][3] + langextra[ibody][3];
torque[ibody][1] = all[ibody][4] + langextra[ibody][4];
torque[ibody][2] = all[ibody][5] + langextra[ibody][5];
// update vcm by 1/2 step
dtfm = dtf / masstotal[ibody];
vcm[ibody][0] += dtfm * fcm[ibody][0] * fflag[ibody][0];
vcm[ibody][1] += dtfm * fcm[ibody][1] * fflag[ibody][1];
vcm[ibody][2] += dtfm * fcm[ibody][2] * fflag[ibody][2];
// update angular momentum by 1/2 step
angmom[ibody][0] += dtf * torque[ibody][0] * tflag[ibody][0];
angmom[ibody][1] += dtf * torque[ibody][1] * tflag[ibody][1];
angmom[ibody][2] += dtf * torque[ibody][2] * tflag[ibody][2];
MathExtra::angmom_to_omega(angmom[ibody],ex_space[ibody],ey_space[ibody],
ez_space[ibody],inertia[ibody],omega[ibody]);
}
// set velocity/rotation of atoms in rigid bodies
// virial is already setup from initial_integrate
set_v();
}
/* ----------------------------------------------------------------------
apply evolution operators to quat, quat momentum
see Miller paper cited in fix rigid/nvt and fix rigid/npt
------------------------------------------------------------------------- */
void FixRigid::no_squish_rotate(int k, double *p, double *q,
double *inertia, double dt)
{
double phi,c_phi,s_phi,kp[4],kq[4];
// apply permuation operator on p and q, get kp and kq
if (k == 1) {
kq[0] = -q[1]; kp[0] = -p[1];
kq[1] = q[0]; kp[1] = p[0];
kq[2] = q[3]; kp[2] = p[3];
kq[3] = -q[2]; kp[3] = -p[2];
} else if (k == 2) {
kq[0] = -q[2]; kp[0] = -p[2];
kq[1] = -q[3]; kp[1] = -p[3];
kq[2] = q[0]; kp[2] = p[0];
kq[3] = q[1]; kp[3] = p[1];
} else if (k == 3) {
kq[0] = -q[3]; kp[0] = -p[3];
kq[1] = q[2]; kp[1] = p[2];
kq[2] = -q[1]; kp[2] = -p[1];
kq[3] = q[0]; kp[3] = p[0];
}
// obtain phi, cosines and sines
phi = p[0]*kq[0] + p[1]*kq[1] + p[2]*kq[2] + p[3]*kq[3];
if (fabs(inertia[k-1]) < 1e-6) phi *= 0.0;
else phi /= 4.0 * inertia[k-1];
c_phi = cos(dt * phi);
s_phi = sin(dt * phi);
// advance p and q
p[0] = c_phi*p[0] + s_phi*kp[0];
p[1] = c_phi*p[1] + s_phi*kp[1];
p[2] = c_phi*p[2] + s_phi*kp[2];
p[3] = c_phi*p[3] + s_phi*kp[3];
q[0] = c_phi*q[0] + s_phi*kq[0];
q[1] = c_phi*q[1] + s_phi*kq[1];
q[2] = c_phi*q[2] + s_phi*kq[2];
q[3] = c_phi*q[3] + s_phi*kq[3];
}
/* ---------------------------------------------------------------------- */
void FixRigid::initial_integrate_respa(int vflag, int ilevel, int iloop)
{
dtv = step_respa[ilevel];
dtf = 0.5 * step_respa[ilevel] * force->ftm2v;
dtq = 0.5 * step_respa[ilevel];
if (ilevel == 0) initial_integrate(vflag);
else final_integrate();
}
/* ---------------------------------------------------------------------- */
void FixRigid::final_integrate_respa(int ilevel, int iloop)
{
dtf = 0.5 * step_respa[ilevel] * force->ftm2v;
final_integrate();
}
/* ----------------------------------------------------------------------
remap xcm of each rigid body back into periodic simulation box
done during pre_neighbor so will be after call to pbc()
and after fix_deform::pre_exchange() may have flipped box
use domain->remap() in case xcm is far away from box
due to 1st definition of rigid body or due to box flip
if don't do this, then atoms of a body which drifts far away
from a triclinic box will be remapped back into box
with huge displacements when the box tilt changes via set_x()
adjust image flag of body and image flags of all atoms in body
------------------------------------------------------------------------- */
void FixRigid::pre_neighbor()
{
tagint original,oldimage,newimage;
for (int ibody = 0; ibody < nbody; ibody++) {
original = imagebody[ibody];
domain->remap(xcm[ibody],imagebody[ibody]);
if (original == imagebody[ibody]) remapflag[ibody][3] = 0;
else {
oldimage = original & IMGMASK;
newimage = imagebody[ibody] & IMGMASK;
remapflag[ibody][0] = newimage - oldimage;
oldimage = (original >> IMGBITS) & IMGMASK;
newimage = (imagebody[ibody] >> IMGBITS) & IMGMASK;
remapflag[ibody][1] = newimage - oldimage;
oldimage = original >> IMG2BITS;
newimage = imagebody[ibody] >> IMG2BITS;
remapflag[ibody][2] = newimage - oldimage;
remapflag[ibody][3] = 1;
}
}
// adjust image flags of any atom in a rigid body whose xcm was remapped
tagint *image = atom->image;
int nlocal = atom->nlocal;
int ibody;
tagint idim,otherdims;
for (int i = 0; i < nlocal; i++) {
if (body[i] == -1) continue;
if (remapflag[body[i]][3] == 0) continue;
ibody = body[i];
if (remapflag[ibody][0]) {
idim = image[i] & IMGMASK;
otherdims = image[i] ^ idim;
idim -= remapflag[ibody][0];
idim &= IMGMASK;
image[i] = otherdims | idim;
}
if (remapflag[ibody][1]) {
idim = (image[i] >> IMGBITS) & IMGMASK;
otherdims = image[i] ^ (idim << IMGBITS);
idim -= remapflag[ibody][1];
idim &= IMGMASK;
image[i] = otherdims | (idim << IMGBITS);
}
if (remapflag[ibody][2]) {
idim = image[i] >> IMG2BITS;
otherdims = image[i] ^ (idim << IMG2BITS);
idim -= remapflag[ibody][2];
idim &= IMGMASK;
image[i] = otherdims | (idim << IMG2BITS);
}
}
}
/* ----------------------------------------------------------------------
count # of DOF removed by rigid bodies for atoms in igroup
return total count of DOF
------------------------------------------------------------------------- */
int FixRigid::dof(int tgroup)
{
int tgroupbit = group->bitmask[tgroup];
// nall = # of point particles in each rigid body
// mall = # of finite-size particles in each rigid body
// particles must also be in temperature group
int *mask = atom->mask;
int nlocal = atom->nlocal;
int *ncount = new int[nbody];
int *mcount = new int[nbody];
for (int ibody = 0; ibody < nbody; ibody++)
ncount[ibody] = mcount[ibody] = 0;
for (int i = 0; i < nlocal; i++)
if (body[i] >= 0 && mask[i] & tgroupbit) {
if (extended && eflags[i]) mcount[body[i]]++;
else ncount[body[i]]++;
}
int *nall = new int[nbody];
int *mall = new int[nbody];
MPI_Allreduce(ncount,nall,nbody,MPI_INT,MPI_SUM,world);
MPI_Allreduce(mcount,mall,nbody,MPI_INT,MPI_SUM,world);
// warn if nall+mall != nrigid for any body included in temperature group
int flag = 0;
for (int ibody = 0; ibody < nbody; ibody++) {
if (nall[ibody]+mall[ibody] > 0 &&
nall[ibody]+mall[ibody] != nrigid[ibody]) flag = 1;
}
if (flag && me == 0)
error->warning(FLERR,"Computing temperature of portions of rigid bodies");
// remove appropriate DOFs for each rigid body wholly in temperature group
// N = # of point particles in body
// M = # of finite-size particles in body
// 3d body has 3N + 6M dof to start with
// 2d body has 2N + 3M dof to start with
// 3d point-particle body with all non-zero I should have 6 dof, remove 3N-6
// 3d point-particle body (linear) with a 0 I should have 5 dof, remove 3N-5
// 2d point-particle body should have 3 dof, remove 2N-3
// 3d body with any finite-size M should have 6 dof, remove (3N+6M) - 6
// 2d body with any finite-size M should have 3 dof, remove (2N+3M) - 3
int n = 0;
if (domain->dimension == 3) {
for (int ibody = 0; ibody < nbody; ibody++)
if (nall[ibody]+mall[ibody] == nrigid[ibody]) {
n += 3*nall[ibody] + 6*mall[ibody] - 6;
if (inertia[ibody][0] == 0.0 || inertia[ibody][1] == 0.0 ||
inertia[ibody][2] == 0.0) n++;
}
} else if (domain->dimension == 2) {
for (int ibody = 0; ibody < nbody; ibody++)
if (nall[ibody]+mall[ibody] == nrigid[ibody])
n += 2*nall[ibody] + 3*mall[ibody] - 3;
}
delete [] ncount;
delete [] mcount;
delete [] nall;
delete [] mall;
return n;
}
/* ----------------------------------------------------------------------
adjust xcm of each rigid body due to box deformation
called by various fixes that change box size/shape
flag = 0/1 means map from box to lamda coords or vice versa
------------------------------------------------------------------------- */
void FixRigid::deform(int flag)
{
if (flag == 0)
for (int ibody = 0; ibody < nbody; ibody++)
domain->x2lamda(xcm[ibody],xcm[ibody]);
else
for (int ibody = 0; ibody < nbody; ibody++)
domain->lamda2x(xcm[ibody],xcm[ibody]);
}
/* ----------------------------------------------------------------------
set space-frame coords and velocity of each atom in each rigid body
set orientation and rotation of extended particles
x = Q displace + Xcm, mapped back to periodic box
v = Vcm + (W cross (x - Xcm))
------------------------------------------------------------------------- */
void FixRigid::set_xv()
{
int ibody,itype;
int xbox,ybox,zbox;
double x0,x1,x2,v0,v1,v2,fc0,fc1,fc2,massone;
double xy,xz,yz;
double ione[3],exone[3],eyone[3],ezone[3],vr[6],p[3][3];
tagint *image = atom->image;
double **x = atom->x;
double **v = atom->v;
double **f = atom->f;
double *rmass = atom->rmass;
double *mass = atom->mass;
int *type = atom->type;
int nlocal = atom->nlocal;
double xprd = domain->xprd;
double yprd = domain->yprd;
double zprd = domain->zprd;
if (triclinic) {
xy = domain->xy;
xz = domain->xz;
yz = domain->yz;
}
// set x and v of each atom
for (int i = 0; i < nlocal; i++) {
if (body[i] < 0) continue;
ibody = body[i];
xbox = (image[i] & IMGMASK) - IMGMAX;
ybox = (image[i] >> IMGBITS & IMGMASK) - IMGMAX;
zbox = (image[i] >> IMG2BITS) - IMGMAX;
// save old positions and velocities for virial
if (evflag) {
if (triclinic == 0) {
x0 = x[i][0] + xbox*xprd;
x1 = x[i][1] + ybox*yprd;
x2 = x[i][2] + zbox*zprd;
} else {
x0 = x[i][0] + xbox*xprd + ybox*xy + zbox*xz;
x1 = x[i][1] + ybox*yprd + zbox*yz;
x2 = x[i][2] + zbox*zprd;
}
v0 = v[i][0];
v1 = v[i][1];
v2 = v[i][2];
}
// x = displacement from center-of-mass, based on body orientation
// v = vcm + omega around center-of-mass
MathExtra::matvec(ex_space[ibody],ey_space[ibody],
ez_space[ibody],displace[i],x[i]);
v[i][0] = omega[ibody][1]*x[i][2] - omega[ibody][2]*x[i][1] +
vcm[ibody][0];
v[i][1] = omega[ibody][2]*x[i][0] - omega[ibody][0]*x[i][2] +
vcm[ibody][1];
v[i][2] = omega[ibody][0]*x[i][1] - omega[ibody][1]*x[i][0] +
vcm[ibody][2];
// add center of mass to displacement
// map back into periodic box via xbox,ybox,zbox
// for triclinic, add in box tilt factors as well
if (triclinic == 0) {
x[i][0] += xcm[ibody][0] - xbox*xprd;
x[i][1] += xcm[ibody][1] - ybox*yprd;
x[i][2] += xcm[ibody][2] - zbox*zprd;
} else {
x[i][0] += xcm[ibody][0] - xbox*xprd - ybox*xy - zbox*xz;
x[i][1] += xcm[ibody][1] - ybox*yprd - zbox*yz;
x[i][2] += xcm[ibody][2] - zbox*zprd;
}
// virial = unwrapped coords dotted into body constraint force
// body constraint force = implied force due to v change minus f external
// assume f does not include forces internal to body
// 1/2 factor b/c final_integrate contributes other half
// assume per-atom contribution is due to constraint force on that atom
if (evflag) {
if (rmass) massone = rmass[i];
else massone = mass[type[i]];
fc0 = massone*(v[i][0] - v0)/dtf - f[i][0];
fc1 = massone*(v[i][1] - v1)/dtf - f[i][1];
fc2 = massone*(v[i][2] - v2)/dtf - f[i][2];
vr[0] = 0.5*x0*fc0;
vr[1] = 0.5*x1*fc1;
vr[2] = 0.5*x2*fc2;
vr[3] = 0.5*x0*fc1;
vr[4] = 0.5*x0*fc2;
vr[5] = 0.5*x1*fc2;
v_tally(1,&i,1.0,vr);
}
}
// set orientation, omega, angmom of each extended particle
if (extended) {
double theta_body,theta;
double *shape,*quatatom,*inertiaatom;
AtomVecEllipsoid::Bonus *ebonus;
if (avec_ellipsoid) ebonus = avec_ellipsoid->bonus;
AtomVecLine::Bonus *lbonus;
if (avec_line) lbonus = avec_line->bonus;
AtomVecTri::Bonus *tbonus;
if (avec_tri) tbonus = avec_tri->bonus;
double **omega_one = atom->omega;
double **angmom_one = atom->angmom;
double **mu = atom->mu;
int *ellipsoid = atom->ellipsoid;
int *line = atom->line;
int *tri = atom->tri;
for (int i = 0; i < nlocal; i++) {
if (body[i] < 0) continue;
ibody = body[i];
if (eflags[i] & SPHERE) {
omega_one[i][0] = omega[ibody][0];
omega_one[i][1] = omega[ibody][1];
omega_one[i][2] = omega[ibody][2];
} else if (eflags[i] & ELLIPSOID) {
shape = ebonus[ellipsoid[i]].shape;
quatatom = ebonus[ellipsoid[i]].quat;
MathExtra::quatquat(quat[ibody],orient[i],quatatom);
MathExtra::qnormalize(quatatom);
ione[0] = EINERTIA*rmass[i] * (shape[1]*shape[1] + shape[2]*shape[2]);
ione[1] = EINERTIA*rmass[i] * (shape[0]*shape[0] + shape[2]*shape[2]);
ione[2] = EINERTIA*rmass[i] * (shape[0]*shape[0] + shape[1]*shape[1]);
MathExtra::q_to_exyz(quatatom,exone,eyone,ezone);
MathExtra::omega_to_angmom(omega[ibody],exone,eyone,ezone,ione,
angmom_one[i]);
} else if (eflags[i] & LINE) {
if (quat[ibody][3] >= 0.0) theta_body = 2.0*acos(quat[ibody][0]);
else theta_body = -2.0*acos(quat[ibody][0]);
theta = orient[i][0] + theta_body;
while (theta <= MINUSPI) theta += TWOPI;
while (theta > MY_PI) theta -= TWOPI;
lbonus[line[i]].theta = theta;
omega_one[i][0] = omega[ibody][0];
omega_one[i][1] = omega[ibody][1];
omega_one[i][2] = omega[ibody][2];
} else if (eflags[i] & TRIANGLE) {
inertiaatom = tbonus[tri[i]].inertia;
quatatom = tbonus[tri[i]].quat;
MathExtra::quatquat(quat[ibody],orient[i],quatatom);
MathExtra::qnormalize(quatatom);
MathExtra::q_to_exyz(quatatom,exone,eyone,ezone);
MathExtra::omega_to_angmom(omega[ibody],exone,eyone,ezone,
inertiaatom,angmom_one[i]);
}
if (eflags[i] & DIPOLE) {
MathExtra::quat_to_mat(quat[ibody],p);
MathExtra::matvec(p,dorient[i],mu[i]);
MathExtra::snormalize3(mu[i][3],mu[i],mu[i]);
}
}
}
}
/* ----------------------------------------------------------------------
set space-frame velocity of each atom in a rigid body
set omega and angmom of extended particles
v = Vcm + (W cross (x - Xcm))
------------------------------------------------------------------------- */
void FixRigid::set_v()
{
int ibody,itype;
int xbox,ybox,zbox;
double dx,dy,dz;
double x0,x1,x2,v0,v1,v2,fc0,fc1,fc2,massone;
double xy,xz,yz;
double ione[3],exone[3],eyone[3],ezone[3],delta[3],vr[6];
double **x = atom->x;
double **v = atom->v;
double **f = atom->f;
double *rmass = atom->rmass;
double *mass = atom->mass;
int *type = atom->type;
tagint *image = atom->image;
int nlocal = atom->nlocal;
double xprd = domain->xprd;
double yprd = domain->yprd;
double zprd = domain->zprd;
if (triclinic) {
xy = domain->xy;
xz = domain->xz;
yz = domain->yz;
}
// set v of each atom
for (int i = 0; i < nlocal; i++) {
if (body[i] < 0) continue;
ibody = body[i];
MathExtra::matvec(ex_space[ibody],ey_space[ibody],
ez_space[ibody],displace[i],delta);
// save old velocities for virial
if (evflag) {
v0 = v[i][0];
v1 = v[i][1];
v2 = v[i][2];
}
v[i][0] = omega[ibody][1]*delta[2] - omega[ibody][2]*delta[1] +
vcm[ibody][0];
v[i][1] = omega[ibody][2]*delta[0] - omega[ibody][0]*delta[2] +
vcm[ibody][1];
v[i][2] = omega[ibody][0]*delta[1] - omega[ibody][1]*delta[0] +
vcm[ibody][2];
// virial = unwrapped coords dotted into body constraint force
// body constraint force = implied force due to v change minus f external
// assume f does not include forces internal to body
// 1/2 factor b/c initial_integrate contributes other half
// assume per-atom contribution is due to constraint force on that atom
if (evflag) {
if (rmass) massone = rmass[i];
else massone = mass[type[i]];
fc0 = massone*(v[i][0] - v0)/dtf - f[i][0];
fc1 = massone*(v[i][1] - v1)/dtf - f[i][1];
fc2 = massone*(v[i][2] - v2)/dtf - f[i][2];
xbox = (image[i] & IMGMASK) - IMGMAX;
ybox = (image[i] >> IMGBITS & IMGMASK) - IMGMAX;
zbox = (image[i] >> IMG2BITS) - IMGMAX;
if (triclinic == 0) {
x0 = x[i][0] + xbox*xprd;
x1 = x[i][1] + ybox*yprd;
x2 = x[i][2] + zbox*zprd;
} else {
x0 = x[i][0] + xbox*xprd + ybox*xy + zbox*xz;
x1 = x[i][1] + ybox*yprd + zbox*yz;
x2 = x[i][2] + zbox*zprd;
}
vr[0] = 0.5*x0*fc0;
vr[1] = 0.5*x1*fc1;
vr[2] = 0.5*x2*fc2;
vr[3] = 0.5*x0*fc1;
vr[4] = 0.5*x0*fc2;
vr[5] = 0.5*x1*fc2;
v_tally(1,&i,1.0,vr);
}
}
// set omega, angmom of each extended particle
if (extended) {
double *shape,*quatatom,*inertiaatom;
AtomVecEllipsoid::Bonus *ebonus;
if (avec_ellipsoid) ebonus = avec_ellipsoid->bonus;
AtomVecTri::Bonus *tbonus;
if (avec_tri) tbonus = avec_tri->bonus;
double **omega_one = atom->omega;
double **angmom_one = atom->angmom;
int *ellipsoid = atom->ellipsoid;
int *tri = atom->tri;
for (int i = 0; i < nlocal; i++) {
if (body[i] < 0) continue;
ibody = body[i];
if (eflags[i] & SPHERE) {
omega_one[i][0] = omega[ibody][0];
omega_one[i][1] = omega[ibody][1];
omega_one[i][2] = omega[ibody][2];
} else if (eflags[i] & ELLIPSOID) {
shape = ebonus[ellipsoid[i]].shape;
quatatom = ebonus[ellipsoid[i]].quat;
ione[0] = EINERTIA*rmass[i] * (shape[1]*shape[1] + shape[2]*shape[2]);
ione[1] = EINERTIA*rmass[i] * (shape[0]*shape[0] + shape[2]*shape[2]);
ione[2] = EINERTIA*rmass[i] * (shape[0]*shape[0] + shape[1]*shape[1]);
MathExtra::q_to_exyz(quatatom,exone,eyone,ezone);
MathExtra::omega_to_angmom(omega[ibody],exone,eyone,ezone,ione,
angmom_one[i]);
} else if (eflags[i] & LINE) {
omega_one[i][0] = omega[ibody][0];
omega_one[i][1] = omega[ibody][1];
omega_one[i][2] = omega[ibody][2];
} else if (eflags[i] & TRIANGLE) {
inertiaatom = tbonus[tri[i]].inertia;
quatatom = tbonus[tri[i]].quat;
MathExtra::q_to_exyz(quatatom,exone,eyone,ezone);
MathExtra::omega_to_angmom(omega[ibody],exone,eyone,ezone,
inertiaatom,angmom_one[i]);
}
}
}
}
/* ----------------------------------------------------------------------
one-time initialization of rigid body attributes
extended flags, masstotal, center-of-mass
Cartesian and diagonalized inertia tensor
read per-body attributes from infile if specified
------------------------------------------------------------------------- */
void FixRigid::setup_bodies()
{
int i,itype,ibody;
// extended = 1 if any particle in a rigid body is finite size
// or has a dipole moment
extended = orientflag = dorientflag = 0;
AtomVecEllipsoid::Bonus *ebonus;
if (avec_ellipsoid) ebonus = avec_ellipsoid->bonus;
AtomVecLine::Bonus *lbonus;
if (avec_line) lbonus = avec_line->bonus;
AtomVecTri::Bonus *tbonus;
if (avec_tri) tbonus = avec_tri->bonus;
double **mu = atom->mu;
double *radius = atom->radius;
double *rmass = atom->rmass;
double *mass = atom->mass;
int *ellipsoid = atom->ellipsoid;
int *line = atom->line;
int *tri = atom->tri;
int *type = atom->type;
int nlocal = atom->nlocal;
if (atom->radius_flag || atom->ellipsoid_flag || atom->line_flag ||
atom->tri_flag || atom->mu_flag) {
int flag = 0;
for (i = 0; i < nlocal; i++) {
if (body[i] < 0) continue;
if (radius && radius[i] > 0.0) flag = 1;
if (ellipsoid && ellipsoid[i] >= 0) flag = 1;
if (line && line[i] >= 0) flag = 1;
if (tri && tri[i] >= 0) flag = 1;
if (mu && mu[i][3] > 0.0) flag = 1;
}
MPI_Allreduce(&flag,&extended,1,MPI_INT,MPI_MAX,world);
}
// grow extended arrays and set extended flags for each particle
// orientflag = 4 if any particle stores ellipsoid or tri orientation
// orientflag = 1 if any particle stores line orientation
// dorientflag = 1 if any particle stores dipole orientation
if (extended) {
if (atom->ellipsoid_flag) orientflag = 4;
if (atom->line_flag) orientflag = 1;
if (atom->tri_flag) orientflag = 4;
if (atom->mu_flag) dorientflag = 1;
grow_arrays(atom->nmax);
for (i = 0; i < nlocal; i++) {
eflags[i] = 0;
if (body[i] < 0) continue;
// set to POINT or SPHERE or ELLIPSOID or LINE
if (radius && radius[i] > 0.0) {
eflags[i] |= SPHERE;
eflags[i] |= OMEGA;
eflags[i] |= TORQUE;
} else if (ellipsoid && ellipsoid[i] >= 0) {
eflags[i] |= ELLIPSOID;
eflags[i] |= ANGMOM;
eflags[i] |= TORQUE;
} else if (line && line[i] >= 0) {
eflags[i] |= LINE;
eflags[i] |= OMEGA;
eflags[i] |= TORQUE;
} else if (tri && tri[i] >= 0) {
eflags[i] |= TRIANGLE;
eflags[i] |= ANGMOM;
eflags[i] |= TORQUE;
} else eflags[i] |= POINT;
// set DIPOLE if atom->mu and mu[3] > 0.0
if (atom->mu_flag && mu[i][3] > 0.0)
eflags[i] |= DIPOLE;
}
}
// compute masstotal & center-of-mass of each rigid body
// error if image flag is not 0 in a non-periodic dim
double **x = atom->x;
tagint *image = atom->image;
int *periodicity = domain->periodicity;
double xprd = domain->xprd;
double yprd = domain->yprd;
double zprd = domain->zprd;
double xy = domain->xy;
double xz = domain->xz;
double yz = domain->yz;
for (ibody = 0; ibody < nbody; ibody++)
for (i = 0; i < 6; i++) sum[ibody][i] = 0.0;
int xbox,ybox,zbox;
double massone,xunwrap,yunwrap,zunwrap;
for (i = 0; i < nlocal; i++) {
if (body[i] < 0) continue;
ibody = body[i];
xbox = (image[i] & IMGMASK) - IMGMAX;
ybox = (image[i] >> IMGBITS & IMGMASK) - IMGMAX;
zbox = (image[i] >> IMG2BITS) - IMGMAX;
if (rmass) massone = rmass[i];
else massone = mass[type[i]];
if ((xbox && !periodicity[0]) || (ybox && !periodicity[1]) ||
(zbox && !periodicity[2]))
error->one(FLERR,"Fix rigid atom has non-zero image flag "
"in a non-periodic dimension");
if (triclinic == 0) {
xunwrap = x[i][0] + xbox*xprd;
yunwrap = x[i][1] + ybox*yprd;
zunwrap = x[i][2] + zbox*zprd;
} else {
xunwrap = x[i][0] + xbox*xprd + ybox*xy + zbox*xz;
yunwrap = x[i][1] + ybox*yprd + zbox*yz;
zunwrap = x[i][2] + zbox*zprd;
}
sum[ibody][0] += xunwrap * massone;
sum[ibody][1] += yunwrap * massone;
sum[ibody][2] += zunwrap * massone;
sum[ibody][3] += massone;
}
MPI_Allreduce(sum[0],all[0],6*nbody,MPI_DOUBLE,MPI_SUM,world);
for (ibody = 0; ibody < nbody; ibody++) {
masstotal[ibody] = all[ibody][3];
xcm[ibody][0] = all[ibody][0]/masstotal[ibody];
xcm[ibody][1] = all[ibody][1]/masstotal[ibody];
xcm[ibody][2] = all[ibody][2]/masstotal[ibody];
}
// overwrite masstotal and center-of-mass with file values
// inbody[i] = 0/1 if Ith rigid body is initialized by file
int *inbody;
if (infile) {
memory->create(inbody,nbody,"rigid:inbody");
for (ibody = 0; ibody < nbody; ibody++) inbody[ibody] = 0;
readfile(0,masstotal,xcm,inbody);
}
// set image flags for each rigid body to default values
// then remap the xcm of each body back into simulation box if needed
for (ibody = 0; ibody < nbody; ibody++)
imagebody[ibody] = ((tagint) IMGMAX << IMG2BITS) |
((tagint) IMGMAX << IMGBITS) | IMGMAX;
pre_neighbor();
// compute 6 moments of inertia of each body in Cartesian reference frame
// dx,dy,dz = coords relative to center-of-mass
// symmetric 3x3 inertia tensor stored in Voigt notation as 6-vector
double dx,dy,dz,rad;
for (ibody = 0; ibody < nbody; ibody++)
for (i = 0; i < 6; i++) sum[ibody][i] = 0.0;
for (i = 0; i < nlocal; i++) {
if (body[i] < 0) continue;
ibody = body[i];
xbox = (image[i] & IMGMASK) - IMGMAX;
ybox = (image[i] >> IMGBITS & IMGMASK) - IMGMAX;
zbox = (image[i] >> IMG2BITS) - IMGMAX;
if (triclinic == 0) {
xunwrap = x[i][0] + xbox*xprd;
yunwrap = x[i][1] + ybox*yprd;
zunwrap = x[i][2] + zbox*zprd;
} else {
xunwrap = x[i][0] + xbox*xprd + ybox*xy + zbox*xz;
yunwrap = x[i][1] + ybox*yprd + zbox*yz;
zunwrap = x[i][2] + zbox*zprd;
}
dx = xunwrap - xcm[ibody][0];
dy = yunwrap - xcm[ibody][1];
dz = zunwrap - xcm[ibody][2];
if (rmass) massone = rmass[i];
else massone = mass[type[i]];
sum[ibody][0] += massone * (dy*dy + dz*dz);
sum[ibody][1] += massone * (dx*dx + dz*dz);
sum[ibody][2] += massone * (dx*dx + dy*dy);
sum[ibody][3] -= massone * dy*dz;
sum[ibody][4] -= massone * dx*dz;
sum[ibody][5] -= massone * dx*dy;
}
// extended particles may contribute extra terms to moments of inertia
if (extended) {
double ivec[6];
double *shape,*quatatom,*inertiaatom;
double length,theta;
for (i = 0; i < nlocal; i++) {
if (body[i] < 0) continue;
ibody = body[i];
if (rmass) massone = rmass[i];
else massone = mass[type[i]];
if (eflags[i] & SPHERE) {
sum[ibody][0] += SINERTIA*massone * radius[i]*radius[i];
sum[ibody][1] += SINERTIA*massone * radius[i]*radius[i];
sum[ibody][2] += SINERTIA*massone * radius[i]*radius[i];
} else if (eflags[i] & ELLIPSOID) {
shape = ebonus[ellipsoid[i]].shape;
quatatom = ebonus[ellipsoid[i]].quat;
MathExtra::inertia_ellipsoid(shape,quatatom,massone,ivec);
sum[ibody][0] += ivec[0];
sum[ibody][1] += ivec[1];
sum[ibody][2] += ivec[2];
sum[ibody][3] += ivec[3];
sum[ibody][4] += ivec[4];
sum[ibody][5] += ivec[5];
} else if (eflags[i] & LINE) {
length = lbonus[line[i]].length;
theta = lbonus[line[i]].theta;
MathExtra::inertia_line(length,theta,massone,ivec);
sum[ibody][0] += ivec[0];
sum[ibody][1] += ivec[1];
sum[ibody][2] += ivec[2];
sum[ibody][3] += ivec[3];
sum[ibody][4] += ivec[4];
sum[ibody][5] += ivec[5];
} else if (eflags[i] & TRIANGLE) {
inertiaatom = tbonus[tri[i]].inertia;
quatatom = tbonus[tri[i]].quat;
MathExtra::inertia_triangle(inertiaatom,quatatom,massone,ivec);
sum[ibody][0] += ivec[0];
sum[ibody][1] += ivec[1];
sum[ibody][2] += ivec[2];
sum[ibody][3] += ivec[3];
sum[ibody][4] += ivec[4];
sum[ibody][5] += ivec[5];
}
}
}
MPI_Allreduce(sum[0],all[0],6*nbody,MPI_DOUBLE,MPI_SUM,world);
// overwrite Cartesian inertia tensor with file values
if (infile) readfile(1,NULL,all,inbody);
// diagonalize inertia tensor for each body via Jacobi rotations
// inertia = 3 eigenvalues = principal moments of inertia
// evectors and exzy_space = 3 evectors = principal axes of rigid body
int ierror;
double cross[3];
double tensor[3][3],evectors[3][3];
for (ibody = 0; ibody < nbody; ibody++) {
tensor[0][0] = all[ibody][0];
tensor[1][1] = all[ibody][1];
tensor[2][2] = all[ibody][2];
tensor[1][2] = tensor[2][1] = all[ibody][3];
tensor[0][2] = tensor[2][0] = all[ibody][4];
tensor[0][1] = tensor[1][0] = all[ibody][5];
ierror = MathExtra::jacobi(tensor,inertia[ibody],evectors);
if (ierror) error->all(FLERR,
"Insufficient Jacobi rotations for rigid body");
ex_space[ibody][0] = evectors[0][0];
ex_space[ibody][1] = evectors[1][0];
ex_space[ibody][2] = evectors[2][0];
ey_space[ibody][0] = evectors[0][1];
ey_space[ibody][1] = evectors[1][1];
ey_space[ibody][2] = evectors[2][1];
ez_space[ibody][0] = evectors[0][2];
ez_space[ibody][1] = evectors[1][2];
ez_space[ibody][2] = evectors[2][2];
// if any principal moment < scaled EPSILON, set to 0.0
double max;
max = MAX(inertia[ibody][0],inertia[ibody][1]);
max = MAX(max,inertia[ibody][2]);
if (inertia[ibody][0] < EPSILON*max) inertia[ibody][0] = 0.0;
if (inertia[ibody][1] < EPSILON*max) inertia[ibody][1] = 0.0;
if (inertia[ibody][2] < EPSILON*max) inertia[ibody][2] = 0.0;
// enforce 3 evectors as a right-handed coordinate system
// flip 3rd vector if needed
MathExtra::cross3(ex_space[ibody],ey_space[ibody],cross);
if (MathExtra::dot3(cross,ez_space[ibody]) < 0.0)
MathExtra::negate3(ez_space[ibody]);
// create initial quaternion
MathExtra::exyz_to_q(ex_space[ibody],ey_space[ibody],ez_space[ibody],
quat[ibody]);
}
// displace = initial atom coords in basis of principal axes
// set displace = 0.0 for atoms not in any rigid body
// for extended particles, set their orientation wrt to rigid body
double qc[4],delta[3];
double *quatatom;
double theta_body;
for (i = 0; i < nlocal; i++) {
if (body[i] < 0) {
displace[i][0] = displace[i][1] = displace[i][2] = 0.0;
continue;
}
ibody = body[i];
xbox = (image[i] & IMGMASK) - IMGMAX;
ybox = (image[i] >> IMGBITS & IMGMASK) - IMGMAX;
zbox = (image[i] >> IMG2BITS) - IMGMAX;
if (triclinic == 0) {
xunwrap = x[i][0] + xbox*xprd;
yunwrap = x[i][1] + ybox*yprd;
zunwrap = x[i][2] + zbox*zprd;
} else {
xunwrap = x[i][0] + xbox*xprd + ybox*xy + zbox*xz;
yunwrap = x[i][1] + ybox*yprd + zbox*yz;
zunwrap = x[i][2] + zbox*zprd;
}
delta[0] = xunwrap - xcm[ibody][0];
delta[1] = yunwrap - xcm[ibody][1];
delta[2] = zunwrap - xcm[ibody][2];
MathExtra::transpose_matvec(ex_space[ibody],ey_space[ibody],
ez_space[ibody],delta,displace[i]);
if (extended) {
if (eflags[i] & ELLIPSOID) {
quatatom = ebonus[ellipsoid[i]].quat;
MathExtra::qconjugate(quat[ibody],qc);
MathExtra::quatquat(qc,quatatom,orient[i]);
MathExtra::qnormalize(orient[i]);
} else if (eflags[i] & LINE) {
if (quat[ibody][3] >= 0.0) theta_body = 2.0*acos(quat[ibody][0]);
else theta_body = -2.0*acos(quat[ibody][0]);
orient[i][0] = lbonus[line[i]].theta - theta_body;
while (orient[i][0] <= MINUSPI) orient[i][0] += TWOPI;
while (orient[i][0] > MY_PI) orient[i][0] -= TWOPI;
if (orientflag == 4) orient[i][1] = orient[i][2] = orient[i][3] = 0.0;
} else if (eflags[i] & TRIANGLE) {
quatatom = tbonus[tri[i]].quat;
MathExtra::qconjugate(quat[ibody],qc);
MathExtra::quatquat(qc,quatatom,orient[i]);
MathExtra::qnormalize(orient[i]);
} else if (orientflag == 4) {
orient[i][0] = orient[i][1] = orient[i][2] = orient[i][3] = 0.0;
} else if (orientflag == 1)
orient[i][0] = 0.0;
if (eflags[i] & DIPOLE) {
MathExtra::transpose_matvec(ex_space[ibody],ey_space[ibody],
ez_space[ibody],mu[i],dorient[i]);
MathExtra::snormalize3(mu[i][3],dorient[i],dorient[i]);
} else if (dorientflag)
dorient[i][0] = dorient[i][1] = dorient[i][2] = 0.0;
}
}
// test for valid principal moments & axes
// recompute moments of inertia around new axes
// 3 diagonal moments should equal principal moments
// 3 off-diagonal moments should be 0.0
// extended particles may contribute extra terms to moments of inertia
for (ibody = 0; ibody < nbody; ibody++)
for (i = 0; i < 6; i++) sum[ibody][i] = 0.0;
for (i = 0; i < nlocal; i++) {
if (body[i] < 0) continue;
ibody = body[i];
if (rmass) massone = rmass[i];
else massone = mass[type[i]];
sum[ibody][0] += massone *
(displace[i][1]*displace[i][1] + displace[i][2]*displace[i][2]);
sum[ibody][1] += massone *
(displace[i][0]*displace[i][0] + displace[i][2]*displace[i][2]);
sum[ibody][2] += massone *
(displace[i][0]*displace[i][0] + displace[i][1]*displace[i][1]);
sum[ibody][3] -= massone * displace[i][1]*displace[i][2];
sum[ibody][4] -= massone * displace[i][0]*displace[i][2];
sum[ibody][5] -= massone * displace[i][0]*displace[i][1];
}
if (extended) {
double ivec[6];
double *shape,*inertiaatom;
double length;
for (i = 0; i < nlocal; i++) {
if (body[i] < 0) continue;
ibody = body[i];
if (rmass) massone = rmass[i];
else massone = mass[type[i]];
if (eflags[i] & SPHERE) {
sum[ibody][0] += SINERTIA*massone * radius[i]*radius[i];
sum[ibody][1] += SINERTIA*massone * radius[i]*radius[i];
sum[ibody][2] += SINERTIA*massone * radius[i]*radius[i];
} else if (eflags[i] & ELLIPSOID) {
shape = ebonus[ellipsoid[i]].shape;
MathExtra::inertia_ellipsoid(shape,orient[i],massone,ivec);
sum[ibody][0] += ivec[0];
sum[ibody][1] += ivec[1];
sum[ibody][2] += ivec[2];
sum[ibody][3] += ivec[3];
sum[ibody][4] += ivec[4];
sum[ibody][5] += ivec[5];
} else if (eflags[i] & LINE) {
length = lbonus[line[i]].length;
MathExtra::inertia_line(length,orient[i][0],massone,ivec);
sum[ibody][0] += ivec[0];
sum[ibody][1] += ivec[1];
sum[ibody][2] += ivec[2];
sum[ibody][3] += ivec[3];
sum[ibody][4] += ivec[4];
sum[ibody][5] += ivec[5];
} else if (eflags[i] & TRIANGLE) {
inertiaatom = tbonus[tri[i]].inertia;
MathExtra::inertia_triangle(inertiaatom,orient[i],massone,ivec);
sum[ibody][0] += ivec[0];
sum[ibody][1] += ivec[1];
sum[ibody][2] += ivec[2];
sum[ibody][3] += ivec[3];
sum[ibody][4] += ivec[4];
sum[ibody][5] += ivec[5];
}
}
}
MPI_Allreduce(sum[0],all[0],6*nbody,MPI_DOUBLE,MPI_SUM,world);
// error check that re-computed momemts of inertia match diagonalized ones
// do not do test for bodies with params read from infile
double norm;
for (ibody = 0; ibody < nbody; ibody++) {
if (infile && inbody[ibody]) continue;
if (inertia[ibody][0] == 0.0) {
if (fabs(all[ibody][0]) > TOLERANCE)
error->all(FLERR,"Fix rigid: Bad principal moments");
} else {
if (fabs((all[ibody][0]-inertia[ibody][0])/inertia[ibody][0]) >
TOLERANCE) error->all(FLERR,"Fix rigid: Bad principal moments");
}
if (inertia[ibody][1] == 0.0) {
if (fabs(all[ibody][1]) > TOLERANCE)
error->all(FLERR,"Fix rigid: Bad principal moments");
} else {
if (fabs((all[ibody][1]-inertia[ibody][1])/inertia[ibody][1]) >
TOLERANCE) error->all(FLERR,"Fix rigid: Bad principal moments");
}
if (inertia[ibody][2] == 0.0) {
if (fabs(all[ibody][2]) > TOLERANCE)
error->all(FLERR,"Fix rigid: Bad principal moments");
} else {
if (fabs((all[ibody][2]-inertia[ibody][2])/inertia[ibody][2]) >
TOLERANCE) error->all(FLERR,"Fix rigid: Bad principal moments");
}
norm = (inertia[ibody][0] + inertia[ibody][1] + inertia[ibody][2]) / 3.0;
if (fabs(all[ibody][3]/norm) > TOLERANCE ||
fabs(all[ibody][4]/norm) > TOLERANCE ||
fabs(all[ibody][5]/norm) > TOLERANCE)
error->all(FLERR,"Fix rigid: Bad principal moments");
}
if (infile) memory->destroy(inbody);
}
/* ----------------------------------------------------------------------
read per rigid body info from user-provided file
which = 0 to read total mass and center-of-mass, store in vec and array
which = 1 to read 6 moments of inertia, store in array
flag inbody = 0 for bodies whose info is read from file
nlines = # of lines of rigid body info
one line = rigid-ID mass xcm ycm zcm ixx iyy izz ixy ixz iyz
------------------------------------------------------------------------- */
void FixRigid::readfile(int which, double *vec, double **array, int *inbody)
{
int i,j,m,nchunk,id;
int nlines;
FILE *fp;
char *eof,*start,*next,*buf;
char line[MAXLINE];
if (me == 0) {
fp = fopen(infile,"r");
if (fp == NULL) {
char str[128];
sprintf(str,"Cannot open fix rigid infile %s",infile);
error->one(FLERR,str);
}
while (1) {
eof = fgets(line,MAXLINE,fp);
if (eof == NULL) error->one(FLERR,"Unexpected end of fix rigid file");
start = &line[strspn(line," \t\n\v\f\r")];
if (*start != '\0' && *start != '#') break;
}
sscanf(line,"%d",&nlines);
}
MPI_Bcast(&nlines,1,MPI_INT,0,world);
char *buffer = new char[CHUNK*MAXLINE];
char **values = new char*[ATTRIBUTE_PERBODY];
int nread = 0;
while (nread < nlines) {
if (nlines-nread > CHUNK) nchunk = CHUNK;
else nchunk = nlines-nread;
if (me == 0) {
char *eof;
m = 0;
for (i = 0; i < nchunk; i++) {
eof = fgets(&buffer[m],MAXLINE,fp);
if (eof == NULL) error->one(FLERR,"Unexpected end of fix rigid file");
m += strlen(&buffer[m]);
}
if (buffer[m-1] != '\n') strcpy(&buffer[m++],"\n");
m++;
}
MPI_Bcast(&m,1,MPI_INT,0,world);
MPI_Bcast(buffer,m,MPI_CHAR,0,world);
buf = buffer;
next = strchr(buf,'\n');
*next = '\0';
int nwords = atom->count_words(buf);
*next = '\n';
if (nwords != ATTRIBUTE_PERBODY)
error->all(FLERR,"Incorrect rigid body format in fix rigid file");
// loop over lines of rigid body attributes
// tokenize the line into values
// id = rigid body ID
// use ID as-is for SINGLE, as mol-ID for MOLECULE, as-is for GROUP
// for which = 0, store mass/com in vec/array
// for which = 1, store interia tensor array, invert 3,4,5 values to Voigt
for (int i = 0; i < nchunk; i++) {
next = strchr(buf,'\n');
values[0] = strtok(buf," \t\n\r\f");
for (j = 1; j < nwords; j++)
values[j] = strtok(NULL," \t\n\r\f");
id = atoi(values[0]);
if (rstyle == MOLECULE) {
if (id <= 0 || id > maxmol)
error->all(FLERR,"Invalid rigid body ID in fix rigid file");
id = mol2body[id];
} else id--;
if (id < 0 || id >= nbody)
error->all(FLERR,"Invalid rigid body ID in fix rigid file");
inbody[id] = 1;
if (which == 0) {
vec[id] = atof(values[1]);
array[id][0] = atof(values[2]);
array[id][1] = atof(values[3]);
array[id][2] = atof(values[4]);
} else {
array[id][0] = atof(values[5]);
array[id][1] = atof(values[6]);
array[id][2] = atof(values[7]);
array[id][3] = atof(values[10]);
array[id][4] = atof(values[9]);
array[id][5] = atof(values[8]);
}
buf = next + 1;
}
nread += nchunk;
}
if (me == 0) fclose(fp);
delete [] buffer;
delete [] values;
}
/* ----------------------------------------------------------------------
memory usage of local atom-based arrays
------------------------------------------------------------------------- */
double FixRigid::memory_usage()
{
int nmax = atom->nmax;
double bytes = nmax * sizeof(int);
bytes += nmax*3 * sizeof(double);
bytes += maxvatom*6 * sizeof(double); // vatom
if (extended) {
bytes += nmax * sizeof(int);
if (orientflag) bytes = nmax*orientflag * sizeof(double);
if (dorientflag) bytes = nmax*3 * sizeof(double);
}
return bytes;
}
/* ----------------------------------------------------------------------
allocate local atom-based arrays
------------------------------------------------------------------------- */
void FixRigid::grow_arrays(int nmax)
{
memory->grow(body,nmax,"rigid:body");
memory->grow(displace,nmax,3,"rigid:displace");
if (extended) {
memory->grow(eflags,nmax,"rigid:eflags");
if (orientflag) memory->grow(orient,nmax,orientflag,"rigid:orient");
if (dorientflag) memory->grow(dorient,nmax,3,"rigid:dorient");
}
}
/* ----------------------------------------------------------------------
copy values within local atom-based arrays
------------------------------------------------------------------------- */
void FixRigid::copy_arrays(int i, int j, int delflag)
{
body[j] = body[i];
displace[j][0] = displace[i][0];
displace[j][1] = displace[i][1];
displace[j][2] = displace[i][2];
if (extended) {
eflags[j] = eflags[i];
for (int k = 0; k < orientflag; k++)
orient[j][k] = orient[i][k];
if (dorientflag) {
dorient[j][0] = dorient[i][0];
dorient[j][1] = dorient[i][1];
dorient[j][2] = dorient[i][2];
}
}
}
/* ----------------------------------------------------------------------
initialize one atom's array values, called when atom is created
------------------------------------------------------------------------- */
void FixRigid::set_arrays(int i)
{
body[i] = -1;
displace[i][0] = 0.0;
displace[i][1] = 0.0;
displace[i][2] = 0.0;
}
/* ----------------------------------------------------------------------
pack values in local atom-based arrays for exchange with another proc
------------------------------------------------------------------------- */
int FixRigid::pack_exchange(int i, double *buf)
{
buf[0] = body[i];
buf[1] = displace[i][0];
buf[2] = displace[i][1];
buf[3] = displace[i][2];
if (!extended) return 4;
int m = 4;
buf[m++] = eflags[i];
for (int j = 0; j < orientflag; j++)
buf[m++] = orient[i][j];
if (dorientflag) {
buf[m++] = dorient[i][0];
buf[m++] = dorient[i][1];
buf[m++] = dorient[i][2];
}
return m;
}
/* ----------------------------------------------------------------------
unpack values in local atom-based arrays from exchange with another proc
------------------------------------------------------------------------- */
int FixRigid::unpack_exchange(int nlocal, double *buf)
{
body[nlocal] = static_cast<int> (buf[0]);
displace[nlocal][0] = buf[1];
displace[nlocal][1] = buf[2];
displace[nlocal][2] = buf[3];
if (!extended) return 4;
int m = 4;
eflags[nlocal] = static_cast<int> (buf[m++]);
for (int j = 0; j < orientflag; j++)
orient[nlocal][j] = buf[m++];
if (dorientflag) {
dorient[nlocal][0] = buf[m++];
dorient[nlocal][1] = buf[m++];
dorient[nlocal][2] = buf[m++];
}
return m;
}
/* ---------------------------------------------------------------------- */
void FixRigid::reset_dt()
{
dtv = update->dt;
dtf = 0.5 * update->dt * force->ftm2v;
dtq = 0.5 * update->dt;
}
/* ----------------------------------------------------------------------
return temperature of collection of rigid bodies
non-active DOF are removed by fflag/tflag and in tfactor
------------------------------------------------------------------------- */
double FixRigid::compute_scalar()
{
double wbody[3],rot[3][3];
double t = 0.0;
for (int i = 0; i < nbody; i++) {
t += masstotal[i] * (fflag[i][0]*vcm[i][0]*vcm[i][0] +
fflag[i][1]*vcm[i][1]*vcm[i][1] + \
fflag[i][2]*vcm[i][2]*vcm[i][2]);
// wbody = angular velocity in body frame
MathExtra::quat_to_mat(quat[i],rot);
MathExtra::transpose_matvec(rot,angmom[i],wbody);
if (inertia[i][0] == 0.0) wbody[0] = 0.0;
else wbody[0] /= inertia[i][0];
if (inertia[i][1] == 0.0) wbody[1] = 0.0;
else wbody[1] /= inertia[i][1];
if (inertia[i][2] == 0.0) wbody[2] = 0.0;
else wbody[2] /= inertia[i][2];
t += tflag[i][0]*inertia[i][0]*wbody[0]*wbody[0] +
tflag[i][1]*inertia[i][1]*wbody[1]*wbody[1] +
tflag[i][2]*inertia[i][2]*wbody[2]*wbody[2];
}
t *= tfactor;
return t;
}
/* ---------------------------------------------------------------------- */
void *FixRigid::extract(const char *str, int &dim)
{
if (strcmp(str,"body") == 0) {
dim = 1;
return body;
}
if (strcmp(str,"masstotal") == 0) {
dim = 1;
return masstotal;
}
if (strcmp(str,"t_target") == 0) {
dim = 0;
return &t_target;
}
return NULL;
}
/* ----------------------------------------------------------------------
return attributes of a rigid body
15 values per body
xcm = 0,1,2; vcm = 3,4,5; fcm = 6,7,8; torque = 9,10,11; image = 12,13,14
------------------------------------------------------------------------- */
double FixRigid::compute_array(int i, int j)
{
if (j < 3) return xcm[i][j];
if (j < 6) return vcm[i][j-3];
if (j < 9) return fcm[i][j-6];
if (j < 12) return torque[i][j-9];
if (j == 12) return (imagebody[i] & IMGMASK) - IMGMAX;
if (j == 13) return (imagebody[i] >> IMGBITS & IMGMASK) - IMGMAX;
return (imagebody[i] >> IMG2BITS) - IMGMAX;
}
Event Timeline
Log In to Comment