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/* -*- 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.
------------------------------------------------------------------------- */
#ifdef COMMAND_CLASS
CommandStyle(velocity,Velocity)
#else
#ifndef LMP_VELOCITY_H
#define LMP_VELOCITY_H
#include "pointers.h"
namespace LAMMPS_NS {
class Velocity : protected Pointers {
public:
Velocity(class LAMMPS *);
void command(int, char **);
void init_external(const char *);
void options(int, char **);
void create(double, int);
private:
int igroup,groupbit;
int style;
int dist_flag,sum_flag,momentum_flag,rotation_flag;
int bias_flag,loop_flag,scale_flag,rfix;
double xscale,yscale,zscale;
class Compute *temperature;
void set(int, char **);
void scale(int, char **);
void ramp(int, char **);
void zero(int, char **);
void rescale(double, double);
void zero_momentum();
void zero_rotation();
};
}
#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: Velocity command before simulation box is defined
The velocity command cannot be used before a read_data, read_restart,
or create_box command.
E: Velocity command with no atoms existing
A velocity command has been used, but no atoms yet exist.
E: Could not find velocity group ID
A group ID used in the velocity command does not exist.
W: Changing velocities of atoms in rigid bodies. This has no effect unless rigid bodies are rebuild
UNDOCUMENTED
W: Mismatch between velocity and compute groups
The temperature computation used by the velocity command will not be
on the same group of atoms that velocities are being set for.
E: Too big a problem to use velocity create loop all
The system size must fit in a 32-bit integer to use this option.
E: Cannot use velocity create loop all unless atoms have IDs
Atoms in the simulation to do not have IDs, so this style
of velocity creation cannot be performed.
E: Atom IDs must be consecutive for velocity create loop all
Self-explanatory.
E: Variable name for velocity set does not exist
Self-explanatory.
E: Variable for velocity set is invalid style
Only atom-style variables can be used.
E: Cannot set non-zero z velocity for 2d simulation
Self-explanatory.
E: Cannot set variable z velocity for 2d simulation
Self-explanatory.
E: Velocity ramp in z for a 2d problem
Self-explanatory.
E: Velocity rigid used with non-rigid fix-ID
Self-explanatory.
E: Attempting to rescale a 0.0 temperature
Cannot rescale a temperature that is already 0.0.
E: Cannot zero momentum of no atoms
Self-explanatory.
E: Could not find velocity temperature ID
The compute ID needed by the velocity command to compute temperature
does not exist.
E: Velocity temperature ID does not compute temperature
The compute ID given to the velocity command must compute
temperature.
E: Fix ID for velocity does not exist
Self-explanatory.
E: Cannot use velocity bias command without temp keyword
Self-explanatory.
E: Velocity temperature ID does calculate a velocity bias
The specified compute must compute a bias for temperature.
*/