/* ----------------------------------------------------------------------
    This is the

    ██╗     ██╗ ██████╗  ██████╗  ██████╗ ██╗  ██╗████████╗███████╗
    ██║     ██║██╔════╝ ██╔════╝ ██╔════╝ ██║  ██║╚══██╔══╝██╔════╝
    ██║     ██║██║  ███╗██║  ███╗██║  ███╗███████║   ██║   ███████╗
    ██║     ██║██║   ██║██║   ██║██║   ██║██╔══██║   ██║   ╚════██║
    ███████╗██║╚██████╔╝╚██████╔╝╚██████╔╝██║  ██║   ██║   ███████║
    ╚══════╝╚═╝ ╚═════╝  ╚═════╝  ╚═════╝ ╚═╝  ╚═╝   ╚═╝   ╚══════╝®

    DEM simulation engine, released by
    DCS Computing Gmbh, Linz, Austria
    http://www.dcs-computing.com, office@dcs-computing.com

    LIGGGHTS® is part of CFDEM®project:
    http://www.liggghts.com | http://www.cfdem.com

    Core developer and main author:
    Christoph Kloss, christoph.kloss@dcs-computing.com

    LIGGGHTS® is open-source, distributed under the terms of the GNU Public
    License, version 2 or later. It is distributed in the hope that it will
    be useful, but WITHOUT ANY WARRANTY; without even the implied warranty
    of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. You should have
    received a copy of the GNU General Public License along with LIGGGHTS®.
    If not, see http://www.gnu.org/licenses . See also top-level README
    and LICENSE files.

    LIGGGHTS® and CFDEM® are registered trade marks of DCS Computing GmbH,
    the producer of the LIGGGHTS® software and the CFDEM®coupling software
    See http://www.cfdem.com/terms-trademark-policy for details.

-------------------------------------------------------------------------
    Contributing author and copyright for this file:
    This file is from LAMMPS, but has been modified. Copyright for
    modification:

    Copyright 2012-     DCS Computing GmbH, Linz
    Copyright 2009-2012 JKU Linz

    Copyright of original file:
    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.
------------------------------------------------------------------------- */

#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 **);

 private:
  int igroup,groupbit;
  int style;
  int dist_flag,sum_flag,momentum_flag,rotation_flag,loop_flag,scale_flag,rfix;
  double xscale,yscale,zscale;
  class FixMultisphere *fix_ms_; 

  void set(int, char **);
  void ramp(int, char **);
  void zero(int, char **);
  void setAngular(int, char **);

  void zero_momentum();
  void zero_rotation();
  void zero_rotation_individual();
};

}

#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: 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: Attempting to rescale a 0.0 temperature

Cannot rescale a temperature that is already 0.0.

E: Cannot zero momentum of 0 atoms

The collection of atoms for which momentum is being computed has no
atoms.

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.

U: Use of velocity with undefined lattice

If units = lattice (the default) for the velocity set or velocity ramp
command, then a lattice must first be defined via the lattice command.

*/
