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lammps/src/USER-CGDNA/fix_nve_dotc_langevin.h
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fix_nve_dotc_langevin.h
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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 FIX_CLASS
FixStyle(nve/dotc/langevin,FixNVEDotcLangevin)
#else
#ifndef LMP_FIX_NVE_DOTC_LANGEVIN_H
#define LMP_FIX_NVE_DOTC_LANGEVIN_H
#include "fix_nve.h"
namespace LAMMPS_NS {
class FixNVEDotcLangevin : public FixNVE {
public:
FixNVEDotcLangevin(class LAMMPS *, int, char **);
virtual ~FixNVEDotcLangevin();
void init();
void initial_integrate(int);
void final_integrate();
private:
double dt,dthlf,dthlfm,dtqrt;
// conversion from 3-vector in space frame to 4-vector in body frame
inline void vec3_to_vec4(const double * q, const double * v3, double * v4)
{
v4[0] = -q[1]*v3[0] - q[2]*v3[1] - q[3]*v3[2];
v4[1] = q[0]*v3[0] + q[3]*v3[1] - q[2]*v3[2];
v4[2] = -q[3]*v3[0] + q[0]*v3[1] + q[1]*v3[2];
v4[3] = q[2]*v3[0] - q[1]*v3[1] + q[0]*v3[2];
}
// conversion from 4-vector in body frame to 3-vector in space frame
inline void vec4_to_vec3(const double * q, const double * v4, double * v3)
{
v3[0] = -q[1]*v4[0] + q[0]*v4[1] - q[3]*v4[2] + q[2]*v4[3];
v3[1] = -q[2]*v4[0] + q[3]*v4[1] + q[0]*v4[2] - q[1]*v4[3];
v3[2] = -q[3]*v4[0] - q[2]*v4[1] + q[1]*v4[2] + q[0]*v4[3];
}
protected:
int seed;
class AtomVecEllipsoid *avec;
double t_start,t_stop,t_period,t_target,tsqrt;
double gamma,Gamma,ascale;
double M,gfactor1,gfactor2;
double gfactor3[3],gfactor4[3],gfactor5[3];
class RanMars *random;
void compute_target();
};
}
#endif
#endif
/* ERROR/WARNING messages:
E: Compute nve/dotc/langevin requires atom style ellipsoid
Self-explanatory.
E: Fix nve/dotc/langevin requires extended particles
This fix can only be used for particles with a shape setting.
*/
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