diff --git a/src/USER-MISC/fix_ti_rs.cpp b/src/USER-MISC/fix_ti_rs.cpp
deleted file mode 100755
index 1090fc02d..000000000
--- a/src/USER-MISC/fix_ti_rs.cpp
+++ /dev/null
@@ -1,199 +0,0 @@
-/* -------------------------------------------------------------------------
- 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.
-------------------------------------------------------------------------- */
-
-/* -------------------------------------------------------------------------
- Contributing authors:
- Rodrigo Freitas (Unicamp/Brazil) - rodrigohb@gmail.com
- Maurice de Koning (Unicamp/Brazil) - dekoning@ifi.unicamp.br
-------------------------------------------------------------------------- */
-
-#include <stdlib.h>
-#include <string.h>
-#include <math.h>
-#include "fix_ti_rs.h"
-#include "atom.h"
-#include "update.h"
-#include "respa.h"
-#include "error.h"
-#include "force.h"
-
-using namespace LAMMPS_NS;
-using namespace FixConst;
-
-/* ---------------------------------------------------------------------- */
-
-// Class constructor initialize all variables.
-
-FixTIRS::FixTIRS(LAMMPS *lmp, int narg, char **arg) : Fix(lmp, narg, arg)
-{
- // Checking the input information.
- if (narg < 7 || narg > 9) error->all(FLERR,"Illegal fix ti/rs command");
-
- // Fix flags.
- vector_flag = 1;
- size_vector = 2;
- global_freq = 1;
- extvector = 1;
-
- // Time variables.
- t_switch = force->bnumeric(FLERR,arg[5]);
- t_equil = force->bnumeric(FLERR,arg[6]);
- t0 = update->ntimestep;
- if (t_switch <= 0) error->all(FLERR,"Illegal fix ti/rs command");
- if (t_equil <= 0) error->all(FLERR,"Illegal fix ti/rs command");
-
- // Coupling parameter limits and initialization.
- l_initial = force->numeric(FLERR,arg[3]);
- l_final = force->numeric(FLERR,arg[4]);
- sf = 1;
- if (narg > 7) {
- if (strcmp(arg[7], "function") == 0) sf = force->inumeric(FLERR,arg[8]);
- else error->all(FLERR,"Illegal fix ti/rs switching function");
- if ((sf<1) || (sf>3))
- error->all(FLERR,"Illegal fix ti/rs switching function");
- }
- lambda = switch_func(0);
- dlambda = dswitch_func(0);
-}
-
-/* ---------------------------------------------------------------------- */
-
-FixTIRS::~FixTIRS()
-{
- // unregister callbacks to this fix from Atom class
- atom->delete_callback(id,0);
- atom->delete_callback(id,1);
-}
-
-/* ---------------------------------------------------------------------- */
-
-int FixTIRS::setmask()
-{
- int mask = 0;
- mask |= INITIAL_INTEGRATE;
- mask |= POST_FORCE;
- return mask;
-}
-
-/* ---------------------------------------------------------------------- */
-
-void FixTIRS::init()
-{
- if (strstr(update->integrate_style,"respa"))
- nlevels_respa = ((Respa *) update->integrate)->nlevels;
-}
-
-/* ---------------------------------------------------------------------- */
-
-void FixTIRS::setup(int vflag)
-{
- if (strstr(update->integrate_style,"verlet"))
- post_force(vflag);
- else {
- ((Respa *) update->integrate)->copy_flevel_f(nlevels_respa-1);
- post_force_respa(vflag,nlevels_respa-1,0);
- ((Respa *) update->integrate)->copy_f_flevel(nlevels_respa-1);
- }
-}
-
-/* ---------------------------------------------------------------------- */
-
-void FixTIRS::min_setup(int vflag)
-{
- post_force(vflag);
-}
-
-
-/* ---------------------------------------------------------------------- */
-
-void FixTIRS::post_force(int vflag)
-{
-
- int *mask = atom->mask;
- int nlocal = atom->nlocal;
- double **f = atom->f;
-
- // Scaling forces.
- for (int i = 0; i < nlocal; i++) {
- if (mask[i] & groupbit) {
- f[i][0] = lambda * f[i][0];
- f[i][1] = lambda * f[i][1];
- f[i][2] = lambda * f[i][2];
- }
- }
-}
-
-/* ---------------------------------------------------------------------- */
-
-void FixTIRS::post_force_respa(int vflag, int ilevel, int iloop)
-{
- if (ilevel == nlevels_respa-1) post_force(vflag);
-}
-
-/* ---------------------------------------------------------------------- */
-
-void FixTIRS::min_post_force(int vflag)
-{
- post_force(vflag);
-}
-
-/* ---------------------------------------------------------------------- */
-
-void FixTIRS::initial_integrate(int vflag)
-{
- // Update the coupling parameter value.
- const bigint t = update->ntimestep - (t0+t_equil);
- const double r_switch = 1.0/t_switch;
-
- if( (t >= 0) && (t <= t_switch) ) {
- lambda = switch_func(t*r_switch);
- dlambda = dswitch_func(t*r_switch);
- }
-
- if( (t >= t_equil+t_switch) && (t <= (t_equil+2*t_switch)) ) {
- lambda = switch_func(1.0 - (t - t_switch - t_equil)*r_switch);
- dlambda = - dswitch_func(1.0 - (t - t_switch - t_equil)*r_switch);
- }
-}
-
-/* ---------------------------------------------------------------------- */
-
-double FixTIRS::compute_vector(int n)
-{
- linfo[0] = lambda;
- linfo[1] = dlambda;
- return linfo[n];
-}
-
-/* ---------------------------------------------------------------------- */
-
-double FixTIRS::switch_func(double t)
-{
- if (sf == 2) return l_initial / (1 + t * (l_initial/l_final - 1));
- if (sf == 3) return l_initial / (1 + log2(1+t) * (l_initial/l_final - 1));
-
- // Default option is sf = 1.
- return l_initial + (l_final - l_initial) * t;
-}
-
-/* ---------------------------------------------------------------------- */
-
-double FixTIRS::dswitch_func(double t)
-{
- double aux = (1.0/l_initial - 1.0/l_final);
- if (sf == 2) return lambda * lambda * aux / t_switch;
- if (sf == 3) return lambda * lambda * aux / (t_switch * log(2) * (1 + t));
-
- // Default option is sf = 1.
- return (l_final-l_initial)/t_switch;
-}
diff --git a/src/USER-MISC/fix_ti_rs.h b/src/USER-MISC/fix_ti_rs.h
deleted file mode 100755
index 0aee21a87..000000000
--- a/src/USER-MISC/fix_ti_rs.h
+++ /dev/null
@@ -1,66 +0,0 @@
-/* -*- c++ -*- ----------------------------------------------------------
- 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.
-------------------------------------------------------------------------- */
-
-/* ----------------------------------------------------------------------
- Contributing authors:
- Rodrigo Freitas (Unicamp/Brazil) - rodrigohb@gmail.com
- Maurice de Koning (Unicamp/Brazil) - dekoning@ifi.unicamp.br
-------------------------------------------------------------------------- */
-
-#ifdef FIX_CLASS
-
-FixStyle(ti/rs,FixTIRS)
-
-#else
-
-#ifndef LMP_FIX_TI_RS_H
-#define LMP_FIX_TI_RS_H
-
-#include "fix.h"
-
-namespace LAMMPS_NS {
-
-class FixTIRS : public Fix {
- public:
- FixTIRS(class LAMMPS *, int, char **);
- ~FixTIRS();
- int setmask();
- void init();
- void setup(int);
- void min_setup(int);
- void post_force(int);
- void post_force_respa(int, int, int);
- void min_post_force(int);
- virtual void initial_integrate(int);
- double compute_vector(int);
-
- private:
- double switch_func(double);
- double dswitch_func(double);
-
- double lambda; // Coupling parameter.
- double dlambda; // Lambda variation with t.
- double l_initial; // Lambda initial value.
- double l_final; // Lambda final value.
- double linfo[2]; // Current lambda status.
- bigint t_switch; // Total switching steps.
- bigint t_equil; // Equilibration time.
- bigint t0; // Initial time.
- int sf; // Switching function option.
- int nlevels_respa;
-};
-
-}
-
-#endif
-#endif
diff --git a/src/USER-MISC/fix_ti_spring.cpp b/src/USER-MISC/fix_ti_spring.cpp
index edb6a7b2c..5f3e9d9cd 100755
--- a/src/USER-MISC/fix_ti_spring.cpp
+++ b/src/USER-MISC/fix_ti_spring.cpp
@@ -1,366 +1,378 @@
/* -------------------------------------------------------------------------
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.
------------------------------------------------------------------------- */
/* -------------------------------------------------------------------------
- Contributing authors:
- Rodrigo Freitas (Unicamp/Brazil) - rodrigohb@gmail.com
+ Contributing authors:
+ Rodrigo Freitas (UC Berkeley) - rodrigof@berkeley.edu
+ Mark Asta (UC Berkeley) - mdasta@berkeley.edu
Maurice de Koning (Unicamp/Brazil) - dekoning@ifi.unicamp.br
------------------------------------------------------------------------- */
-#include <stdlib.h>
-#include <string.h>
+#include "stdlib.h"
+#include "string.h"
#include "fix_ti_spring.h"
#include "atom.h"
#include "update.h"
#include "domain.h"
#include "respa.h"
#include "memory.h"
#include "error.h"
#include "force.h"
-using namespace LAMMPS_NS;
-using namespace FixConst;
+using namespace LAMMPS_NS;
+using namespace FixConst;
+
+static const char cite_ti_spring[] =
+ "ti/spring command:\n\n"
+ "@article{freitas2016,\n"
+ " author={Freitas, Rodrigo and Asta, Mark and de Koning, Maurice},\n"
+ " title={Nonequilibrium free-energy calculation of solids using LAMMPS},\n"
+ " journal={Computational Materials Science},\n"
+ " volume={112},\n"
+ " pages={333--341},\n"
+ " year={2016},\n"
+ " publisher={Elsevier}\n"
+ "}\n\n";
/* ---------------------------------------------------------------------- */
-FixTISpring::FixTISpring(LAMMPS *lmp, int narg, char **arg) :
- Fix(lmp, narg, arg)
+FixTISpring::FixTISpring(LAMMPS *lmp, int narg, char **arg) :
+ Fix(lmp, narg, arg)
{
if (narg < 6 || narg > 8)
error->all(FLERR,"Illegal fix ti/spring command");
// Flags.
restart_peratom = 1;
scalar_flag = 1;
global_freq = 1;
vector_flag = 1;
size_vector = 2;
global_freq = 1;
extscalar = 1;
extvector = 1;
// Spring constant.
k = force->numeric(FLERR,arg[3]);
if (k <= 0.0) error->all(FLERR,"Illegal fix ti/spring command");
// Perform initial allocation of atom-based array.
// Registar with Atom class.
xoriginal = NULL;
grow_arrays(atom->nmax);
atom->add_callback(0);
atom->add_callback(1);
// xoriginal = initial unwrapped positions of atom.
double **x = atom->x;
int *mask = atom->mask;
- imageint *image = atom->image;
+ tagint *image = atom->image;
int nlocal = atom->nlocal;
for (int i = 0; i < nlocal; i++) {
if (mask[i] & groupbit) domain->unmap(x[i],image[i],xoriginal[i]);
else xoriginal[i][0] = xoriginal[i][1] = xoriginal[i][2] = 0.0;
}
// Time variables.
- t_switch = force->bnumeric(FLERR,arg[4]); // Number of steps for switching.
- t_equil = force->bnumeric(FLERR,arg[5]); // Number of steps for equilibration.
+ t_switch = atoi(arg[4]); // Switching time.
+ t_equil = atoi(arg[5]); // Equilibration time.
t0 = update->ntimestep; // Initial time.
- if (t_switch <= 0) error->all(FLERR,"Illegal fix ti/spring command");
- if (t_equil <= 0) error->all(FLERR,"Illegal fix ti/spring command");
+ if (t_switch < 0.0) error->all(FLERR,"Illegal fix ti/spring command");
+ if (t_equil < 0.0) error->all(FLERR,"Illegal fix ti/spring command");
// Coupling parameter initialization.
sf = 1;
if (narg > 6) {
- if (strcmp(arg[6], "function") == 0) sf = force->inumeric(FLERR,arg[7]);
+ if (strcmp(arg[6], "function") == 0) sf = atoi(arg[7]);
else error->all(FLERR,"Illegal fix ti/spring switching function");
- if ((sf!=1) && (sf!=2))
+ if ((sf!=1) && (sf!=2))
error->all(FLERR,"Illegal fix ti/spring switching function");
}
- lambda = switch_func(0);
- dlambda = dswitch_func(0);
+ lambda = switch_func(0);
+ dlambda = dswitch_func(0);
espring = 0.0;
}
/* ---------------------------------------------------------------------- */
FixTISpring::~FixTISpring()
{
// unregister callbacks to this fix from Atom class
atom->delete_callback(id,0);
atom->delete_callback(id,1);
// delete locally stored array
memory->destroy(xoriginal);
}
/* ---------------------------------------------------------------------- */
int FixTISpring::setmask()
{
int mask = 0;
mask |= INITIAL_INTEGRATE;
mask |= POST_FORCE;
mask |= POST_FORCE_RESPA;
mask |= MIN_POST_FORCE;
mask |= THERMO_ENERGY;
return mask;
}
/* ---------------------------------------------------------------------- */
void FixTISpring::init()
{
if (strstr(update->integrate_style,"respa"))
nlevels_respa = ((Respa *) update->integrate)->nlevels;
}
/* ---------------------------------------------------------------------- */
void FixTISpring::setup(int vflag)
{
if (strstr(update->integrate_style,"verlet"))
post_force(vflag);
else {
((Respa *) update->integrate)->copy_flevel_f(nlevels_respa-1);
post_force_respa(vflag,nlevels_respa-1,0);
((Respa *) update->integrate)->copy_f_flevel(nlevels_respa-1);
}
}
/* ---------------------------------------------------------------------- */
void FixTISpring::min_setup(int vflag)
{
post_force(vflag);
}
/* ---------------------------------------------------------------------- */
void FixTISpring::post_force(int vflag)
{
// If on the first equilibration do not calculate forces.
- bigint t = update->ntimestep - t0;
+ int t = update->ntimestep - t0;
if(t < t_equil) return;
double **x = atom->x;
double **f = atom->f;
int *mask = atom->mask;
- imageint *image = atom->image;
+ tagint *image = atom->image;
int nlocal = atom->nlocal;
double dx, dy, dz;
double unwrap[3];
espring = 0.0;
for (int i = 0; i < nlocal; i++)
if (mask[i] & groupbit) {
domain->unmap(x[i],image[i],unwrap);
dx = unwrap[0] - xoriginal[i][0];
dy = unwrap[1] - xoriginal[i][1];
dz = unwrap[2] - xoriginal[i][2];
f[i][0] = (1-lambda) * f[i][0] + lambda * (-k*dx);
f[i][1] = (1-lambda) * f[i][1] + lambda * (-k*dy);
f[i][2] = (1-lambda) * f[i][2] + lambda * (-k*dz);
espring += k * (dx*dx + dy*dy + dz*dz);
}
espring *= 0.5;
}
/* ---------------------------------------------------------------------- */
void FixTISpring::post_force_respa(int vflag, int ilevel, int iloop)
{
if (ilevel == nlevels_respa-1) post_force(vflag);
}
/* ---------------------------------------------------------------------- */
void FixTISpring::min_post_force(int vflag)
{
post_force(vflag);
}
/* ---------------------------------------------------------------------- */
-void FixTISpring::initial_integrate(int vflag)
-{
+void FixTISpring::initial_integrate(int vflag)
+{
// Update the coupling parameter value.
- const bigint t = update->ntimestep - (t0+t_equil);
- const double r_switch = 1.0/t_switch;
+ double t = update->ntimestep - (t0+t_equil);
if( (t >= 0) && (t <= t_switch) ) {
- lambda = switch_func(t*r_switch);
- dlambda = dswitch_func(t*r_switch);
+ lambda = switch_func(t/t_switch);
+ dlambda = dswitch_func(t/t_switch);
}
if( (t >= t_equil+t_switch) && (t <= (t_equil+2*t_switch)) ) {
- lambda = switch_func(1.0 - (t - t_switch - t_equil)*r_switch);
- dlambda = - dswitch_func(1.0 - (t - t_switch - t_equil)*r_switch);
+ lambda = switch_func(1.0 - (t - t_switch - t_equil)/t_switch );
+ dlambda = - dswitch_func(1.0 - (t - t_switch - t_equil)/t_switch );
}
-}
+}
/* ----------------------------------------------------------------------
energy of stretched springs
------------------------------------------------------------------------- */
double FixTISpring::compute_scalar()
{
double all;
MPI_Allreduce(&espring,&all,1,MPI_DOUBLE,MPI_SUM,world);
return all;
}
/* ----------------------------------------------------------------------
information about coupling parameter
------------------------------------------------------------------------- */
double FixTISpring::compute_vector(int n)
{
linfo[0] = lambda;
linfo[1] = dlambda;
return linfo[n];
}
/* ----------------------------------------------------------------------
memory usage of local atom-based array
------------------------------------------------------------------------- */
double FixTISpring::memory_usage()
{
double bytes = atom->nmax*3 * sizeof(double);
return bytes;
}
/* ----------------------------------------------------------------------
allocate atom-based array
------------------------------------------------------------------------- */
void FixTISpring::grow_arrays(int nmax)
{
memory->grow(xoriginal,nmax,3,"fix_ti/spring:xoriginal");
}
/* ----------------------------------------------------------------------
copy values within local atom-based array
------------------------------------------------------------------------- */
void FixTISpring::copy_arrays(int i, int j, int delflag)
{
xoriginal[j][0] = xoriginal[i][0];
xoriginal[j][1] = xoriginal[i][1];
xoriginal[j][2] = xoriginal[i][2];
}
/* ----------------------------------------------------------------------
pack values in local atom-based array for exchange with another proc
------------------------------------------------------------------------- */
int FixTISpring::pack_exchange(int i, double *buf)
{
buf[0] = xoriginal[i][0];
buf[1] = xoriginal[i][1];
buf[2] = xoriginal[i][2];
return 3;
}
/* ----------------------------------------------------------------------
unpack values in local atom-based array from exchange with another proc
------------------------------------------------------------------------- */
int FixTISpring::unpack_exchange(int nlocal, double *buf)
{
xoriginal[nlocal][0] = buf[0];
xoriginal[nlocal][1] = buf[1];
xoriginal[nlocal][2] = buf[2];
return 3;
}
/* ----------------------------------------------------------------------
pack values in local atom-based arrays for restart file
------------------------------------------------------------------------- */
int FixTISpring::pack_restart(int i, double *buf)
{
buf[0] = 4;
buf[1] = xoriginal[i][0];
buf[2] = xoriginal[i][1];
buf[3] = xoriginal[i][2];
return 4;
}
/* ----------------------------------------------------------------------
unpack values from atom->extra array to restart the fix
------------------------------------------------------------------------- */
void FixTISpring::unpack_restart(int nlocal, int nth)
{
double **extra = atom->extra;
// skip to Nth set of extra values
-
+
int m = 0;
for (int i = 0; i < nth; i++) m += static_cast<int> (extra[nlocal][m]);
m++;
-
+
xoriginal[nlocal][0] = extra[nlocal][m++];
xoriginal[nlocal][1] = extra[nlocal][m++];
xoriginal[nlocal][2] = extra[nlocal][m++];
}
/* ----------------------------------------------------------------------
maxsize of any atom's restart data
------------------------------------------------------------------------- */
int FixTISpring::maxsize_restart()
{
return 4;
}
/* ----------------------------------------------------------------------
size of atom nlocal's restart data
------------------------------------------------------------------------- */
int FixTISpring::size_restart(int nlocal)
{
return 4;
}
/* ----------------------------------------------------------------------
Switching function.
------------------------------------------------------------------------- */
-double FixTISpring::switch_func(double t)
+double FixTISpring::switch_func(double t)
{
if (sf == 1) return t;
double t2 = t*t;
double t5 = t2*t2*t;
return ((70.0*t2*t2 - 315.0*t2*t + 540.0*t2 - 420.0*t + 126.0)*t5);
}
/* ----------------------------------------------------------------------
Switching function derivative.
------------------------------------------------------------------------- */
-double FixTISpring::dswitch_func(double t)
+double FixTISpring::dswitch_func(double t)
{
if(sf == 1) return 1.0/t_switch;
double t2 = t*t;
double t4 = t2*t2;
return ((630*t2*t2 - 2520*t2*t + 3780*t2 - 2520*t + 630)*t4) / t_switch;
}
diff --git a/src/USER-MISC/fix_ti_spring.h b/src/USER-MISC/fix_ti_spring.h
index bce342162..9b956e707 100755
--- a/src/USER-MISC/fix_ti_spring.h
+++ b/src/USER-MISC/fix_ti_spring.h
@@ -1,94 +1,95 @@
-/* -*- c++ -*- ----------------------------------------------------------
+/* ----------------------------------------------------------------------
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.
------------------------------------------------------------------------- */
/* ----------------------------------------------------------------------
- Contributing authors:
- Rodrigo Freitas (Unicamp/Brazil) - rodrigohb@gmail.com
+ Contributing authors:
+ Rodrigo Freitas (UC Berkeley) - rodrigof@berkeley.edu
+ Mark Asta (UC Berkeley) - mdasta@berkeley.edu
Maurice de Koning (Unicamp/Brazil) - dekoning@ifi.unicamp.br
------------------------------------------------------------------------- */
#ifdef FIX_CLASS
FixStyle(ti/spring,FixTISpring)
#else
#ifndef LMP_FIX_TI_SPRING_H
#define LMP_FIX_TI_SPRING_H
#include "fix.h"
namespace LAMMPS_NS {
class FixTISpring : public Fix {
public:
FixTISpring(class LAMMPS *, int, char **);
~FixTISpring();
int setmask();
void init();
void setup(int);
void min_setup(int);
void post_force(int);
void post_force_respa(int, int, int);
void min_post_force(int);
void initial_integrate(int);
double compute_scalar();
double compute_vector(int);
-
+
double memory_usage();
void grow_arrays(int);
void copy_arrays(int, int, int);
int pack_exchange(int, double *);
int unpack_exchange(int, double *);
int pack_restart(int, double *);
void unpack_restart(int, int);
int size_restart(int);
int maxsize_restart();
private:
double switch_func(double); // Switching function.
double dswitch_func(double); // Switching function derivative.
double k; // Spring constant.
double espring; // Springs energies.
double **xoriginal; // Original coords of atoms.
double lambda; // Coupling parameter.
double dlambda; // Lambda variation with t.
double linfo[2]; // Current lambda status.
- bigint t_switch; // Total switching steps.
- bigint t_equil; // Equilibration time.
- bigint t0; // Initial time.
+ int t_switch; // Total switching steps.
+ int t_equil; // Equilibration time.
+ int t0; // Initial time.
int sf; // Switching function option.
int nlevels_respa;
};
}
#endif
#endif
/* ERROR/WARNING messages:
E: Illegal ... command
Self-explanatory. Check the input script syntax and compare to the
documentation for the command. You can use -echo screen as a
command-line option when running LAMMPS to see the offending line.
E: Illegal fix ti/spring switching function
Self-explanatory. Check the input script syntax and compare to the
documentation for the command. You can use -echo screen as a
command-line option when running LAMMPS to see the offending line.
*/