retrieve target temperature and pressure from fix npt. add sanity checks. (14c7cf41) · Commits · 郑智淋 / lammps

examples/USER/misc/grem/lj-single/in.gREM

+1 −1

Original line number	Diff line number	Diff line
		@@ -14,7 +14,7 @@ thermo_style custom step temp pe etotal press vol
		timestep 1.0

		fix fxnvt all npt temp ${T0} ${T0} 1000.0 iso ${press} ${press} 10000.0
		fix fxgREM all grem 400 -.01 -30000 ${T0} ${press}
		fix fxgREM all grem 400 -.01 -30000 fxnvt
		thermo_modify press fxgREM_press
		fix_modify fxnvt press fxgREM_press
		run 1000

src/USER-MISC/fix_grem.cpp

+52 −10

Original line number	Diff line number	Diff line
		@@ -47,7 +47,7 @@ enum{NONE,CONSTANT,EQUAL,ATOM};
		FixGrem::FixGrem(LAMMPS lmp, int narg, char *arg) :
		Fix(lmp, narg, arg)
		{
		if (narg < 8) error->all(FLERR,"Illegal fix grem command");
		if (narg < 7) error->all(FLERR,"Illegal fix grem command");

		scalar_flag = 1;
		vector_flag = 1;
		@@ -61,15 +61,17 @@ FixGrem::FixGrem(LAMMPS lmp, int narg, char *arg) :
		lambda = force->numeric(FLERR,arg[3]);
		eta = force->numeric(FLERR,arg[4]);
		h0 = force->numeric(FLERR,arg[5]);
		tbath = force->numeric(FLERR,arg[6]);
		pressref = force->numeric(FLERR,arg[7]);

		int n = strlen(arg[6])+1;
		id_npt = new char[n];
		strcpy(id_npt,arg[6]);

		// create a new compute temp style
		// id = fix-ID + temp
		// compute group = all since pressure is always global (group all)
		// and thus its KE/temperature contribution should use group all

		int n = strlen(id) + 6;
		n = strlen(id) + 6;
		id_temp = new char[n];
		strcpy(id_temp,id);
		strcat(id_temp,"_temp");
		@@ -148,7 +150,7 @@ FixGrem::~FixGrem()
		delete [] id_press;
		delete [] id_ke;
		delete [] id_pe;

		delete [] id_npt;
		}

		/* ---------------------------------------------------------------------- */
		@@ -165,24 +167,61 @@ int FixGrem::setmask()
		void FixGrem::init()
		{

		// add check of sign of eta
		if (domain->triclinic)
		error->all(FLERR,"Triclinic cells are not supported");

		// set temperature and pressure ptrs

		int icompute = modify->find_compute(id_temp);
		if (icompute < 0)
		error->all(FLERR,"Temperature ID for fix scaledforce does not exist");
		error->all(FLERR,"Temperature compute ID for fix grem does not exist");
		temperature = modify->compute[icompute];

		icompute = modify->find_compute(id_ke);
		if (icompute < 0)
		error->all(FLERR,"Ke ID for fix scaledforce does not exist");
		error->all(FLERR,"KE compute ID for fix grem does not exist");
		ke = modify->compute[icompute];

		icompute = modify->find_compute(id_pe);
		if (icompute < 0)
		error->all(FLERR,"Pe ID for fix scaledforce does not exist");
		error->all(FLERR,"PE compute ID for fix grem does not exist");
		pe = modify->compute[icompute];

		int ifix = modify->find_fix(id_npt);
		if (ifix < 0)
		error->all(FLERR,"Fix id for npt fix does not exist");
		Fix *npt = modify->fix[ifix];

		double t_start = (double )npt->extract("t_start",ifix);
		double t_stop = (double )npt->extract("t_stop",ifix);
		if ((t_start != NULL) && (t_stop != NULL) && (ifix == 0)) {
		tbath = *t_start;
		if (t_start != t_stop)
		error->all(FLERR,"Thermostat temperature ramp not allowed");
		} else
		error->all(FLERR,"Problem extracting target temperature from fix npt");

		int p_flag = (int )npt->extract("p_flag",ifix);
		double p_start = (double ) npt->extract("p_start",ifix);
		double p_stop = (double ) npt->extract("p_stop",ifix);
		if ((p_flag != NULL) && (p_start != NULL) && (p_stop != NULL)
		&& (ifix == 1)) {
		ifix = 0;
		pressref = p_start[0];
		if ((p_start[0] != p_stop[0]) \|\| (p_flag[0] != 1)) ++ ifix;
		if ((p_start[1] != p_stop[1]) \|\| (p_flag[0] != 1)) ++ ifix;
		if ((p_start[2] != p_stop[2]) \|\| (p_flag[0] != 1)) ++ ifix;
		if ((p_start[0] != p_start[1]) \|\| (p_start[1] != p_start[2])) ++ifix;
		if ((p_flag[3] != 0) \|\| (p_flag[4] != 0) \|\| (p_flag[5] != 0)) ++ifix;
		if (ifix > 0)
		error->all(FLERR,"Unsupported pressure settings in fix npt");
		} else
		error->all(FLERR,"Problem extracting target pressure from fix npt");

		char *modargs[2];
		modargs[0] = (char *) "press";
		modargs[1] = id_press;
		npt->modify_param(2,modargs);
		}

		/* ---------------------------------------------------------------------- */
		@@ -191,6 +230,9 @@ void FixGrem::setup(int vflag)
		{
		if (strstr(update->integrate_style,"verlet"))
		post_force(vflag);

		if (strstr(update->integrate_style,"respa"))
		error->all(FLERR,"Run style 'respa' is not supported");
		}

		/* ---------------------------------------------------------------------- */

src/USER-MISC/fix_grem.h

+1 −2

Original line number	Diff line number	Diff line
		@@ -40,10 +40,9 @@ class FixGrem : public Fix {
		double lambda,eta,h0,tbath,pressref;

		protected:
		char id_temp,id_press,id_ke,id_pe;
		char id_temp,id_press,id_ke,id_pe,*id_npt;
		class Compute temperature,pressure,ke,pe;
		int pflag,tflag,keflag,peflag;

		};

		}

src/fix_nh.cpp

+12 −0

Original line number	Diff line number	Diff line
		@@ -1700,12 +1700,24 @@ void FixNH::extract(const char str, int &dim)
		dim=0;
		if (strcmp(str,"t_target") == 0) {
		return &t_target;
		} else if (strcmp(str,"t_start") == 0) {
		return &t_start;
		} else if (strcmp(str,"t_stop") == 0) {
		return &t_stop;
		} else if (strcmp(str,"mtchain") == 0) {
		return &mtchain;
		}
		dim=1;
		if (strcmp(str,"eta") == 0) {
		return η
		} else if (strcmp(str,"p_flag") == 0) {
		return &p_flag;
		} else if (strcmp(str,"p_start") == 0) {
		return &p_start;
		} else if (strcmp(str,"p_stop") == 0) {
		return &p_stop;
		} else if (strcmp(str,"p_target") == 0) {
		return &p_target;
		}
		return NULL;
		}

Admin message