fix_shake.h
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fix_shake.h
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			/* ----------------------------------------------------------------------
			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.
			------------------------------------------------------------------------- */

			#ifndef FIX_SHAKE_H
			#define FIX_SHAKE_H

			#include "fix.h"

			namespace LAMMPS_NS {

			class FixShake : public Fix {
			public:
			FixShake(class LAMMPS , int, char *);
			~FixShake();
			int setmask();
			void init();
			void setup(int);
			void pre_neighbor();
			void post_force(int);
			void post_force_respa(int, int, int);

			double memory_usage();
			void grow_arrays(int);
			void copy_arrays(int, int);
			int pack_exchange(int, double *);
			int unpack_exchange(int, double *);
			int pack_comm(int, int , double , int, int *);
			void unpack_comm(int, int, double *);

			int dof(int);
			void reset_dt();

			private:
			int me,nprocs;
			double PI;
			double tolerance; // SHAKE tolerance
			int max_iter; // max # of SHAKE iterations
			int output_every; // SHAKE stat output every so often
			int next_output; // timestep for next output

			// settings from input command
			int bond_flag,angle_flag; // bond/angle types to constrain
			int *type_flag; // constrain bonds to these types
			double *mass_list; // constrain bonds to these masses
			int nmass; // # of masses in mass_list

			double bond_distance,angle_distance; // constraint distances

			int ifix_respa; // rRESPA fix needed by SHAKE
			int nlevels_respa; // copies of needed rRESPA variables
			int *loop_respa;
			double *step_respa;

			double x,v,**f; // local ptrs to atom class quantities
			double mass,rmass;
			int *type;
			int nlocal;
			// atom-based arrays
			int *shake_flag; // 0 if atom not in SHAKE cluster
			// 1 = size 3 angle cluster
			// 2,3,4 = size of bond-only cluster
			int **shake_atom; // global IDs of atoms in cluster
			// central atom is 1st
			// lowest global ID is 1st for size 2
			int **shake_type; // bondtype of each bond in cluster
			// for angle cluster, 3rd value
			// is angletype
			double **xshake; // unconstrained atom coords

			int vflag; // virial flag
			double dtv,dtfsq; // timesteps for trial move
			double dtf_inner,dtf_innerhalf; // timesteps for rRESPA trial move

			int *list; // list of clusters to SHAKE
			int nlist,maxlist; // size and max-size of list

			// stat quantities
			int b_count,b_count_all; // counts for each bond type
			double b_ave,b_max,*b_min; // ave/max/min dist for each bond type
			double b_ave_all,b_max_all,*b_min_all; // MPI summing arrays
			int a_count,a_count_all; // ditto for angle types
			double a_ave,a_max,*a_min;
			double a_ave_all,a_max_all,*a_min_all;

			void find_clusters();
			int masscheck(double);
			void unconstrained_update();
			void shake2(int);
			void shake3(int);
			void shake4(int);
			void shake3angle(int);
			void stats();
			int bondfind(int, int, int);
			int anglefind(int, int, int);
			};

			}

			#endif

lammps/src/fix_shake.h94ddc19477bemaster

fix_shake.hView Options

lammps/src/fix_shake.h
94ddc19477bemaster

fix_shake.h
View Options