Correct calculation of the Forces within the Verlet integrator. Updated doc. (f9315a7a) · Commits · 郑智淋 / lammps

doc/src/min_modify.txt

+4 −3

Changes for doc/src/min_modify.txt: 4 added lines, 3 removed lines.
Original line number	Diff line number	Diff line
		@@ -14,11 +14,12 @@ min_modify keyword values ... :pre

		one or more keyword/value pairs may be listed :ulb,l
		keyword = {dmax} or {line} or {delaystep} or {dt_grow} or {dt_shrink}
		or {alpha0} or {alpha_shrink} or {tmax} or {tmin}
		or {alpha0} or {alpha_shrink} or {tmax} or {tmin} or {integrator}
		{dmax} value = max
		max = maximum distance for line search to move (distance units)
		{line} value = {backtrack} or {quadratic} or {forcezero}
		backtrack,quadratic,forcezero = style of linesearch to use
		{integrator} value = {eulerimplicit} or {eulerexplicit} or {verlet} or {leapfrog} for adaptglok :pre
		{delaystep} value = {int} for adaptglok
		{dt_grow} value = {float} for adaptglok
		{dt_shrink} value = {float} for adaptglok
		@@ -74,7 +75,7 @@ that difference may be smaller than machine epsilon even if atoms
		could move in the gradient direction to reduce forces further.

		The style {adaptglok} has several parameters that can be tuned in order
		to optimize the relaxation: {delaystep}, {dt_grow}, {dt_shrink},
		to optimize the relaxation: {integrator}, {delaystep}, {dt_grow}, {dt_shrink},
		{alpha0}, {alpha_shrink}, {tmax} and {tmin}. The default values have
		been chosen to be reliable in most cases, but one could be willing
		to adapt them for particular cases.
		@@ -87,6 +88,6 @@ to adapt them for particular cases.

		[Default:]

		The option defaults are dmax = 0.1, line = quadratic, delaystep = 20,
		The option defaults are dmax = 0.1, line = quadratic, integrator = eulerimplicit, delaystep = 20,
		dt_grow = 1.1, dt_shrink = 0.5, alpha0 = 0.25, alpha_shrink = 0.99,
		tmax = 2.0 and tmin = 0.02.

doc/src/min_style.txt

+2 −2

Changes for doc/src/min_style.txt: 2 added lines, 2 removed lines.
Original line number	Diff line number	Diff line
		@@ -64,8 +64,8 @@ a minimization.
		Style {adaptglok} is a re-implementation of the style {fire} to better
		fit the published and unpublished optimizations of the method described
		in "(Bitzek)"_#Bitzek. It includes a temporization of the variable
		timestep, a backstep when uphill and a Velocity-Verlet integration
		scheme.
		timestep, a backstep when uphill and different integration
		schemes (Euler, Leap Frog, Velocity-Verlet).

		Either the {quickmin} and {fire} styles are useful in the context of
		nudged elastic band (NEB) calculations via the "neb"_neb.html command.

src/min.cpp

+2 −2

Changes for src/min.cpp: 2 added lines, 2 removed lines.
Original line number	Diff line number	Diff line
		@@ -682,10 +682,10 @@ void Min::modify_params(int narg, char **arg)
		iarg += 2;
		} else if (strcmp(arg[iarg],"integrator") == 0) {
		if (iarg+2 > narg) error->all(FLERR,"Illegal min_modify command");
		if (strcmp(arg[iarg+1],"euler") == 0) integrator = 0;
		if (strcmp(arg[iarg+1],"eulerimplicit") == 0) integrator = 0;
		else if (strcmp(arg[iarg+1],"verlet") == 0) integrator = 1;
		else if (strcmp(arg[iarg+1],"leapfrog") == 0) integrator = 2;
		else if (strcmp(arg[iarg+1],"eulerstandard") == 0) integrator = 3;
		else if (strcmp(arg[iarg+1],"eulerexplicit") == 0) integrator = 3;
		else error->all(FLERR,"Illegal min_modify command");
		iarg += 2;
		} else if (strcmp(arg[iarg],"line") == 0) {

src/min_adaptglok.cpp

+17 −4

Changes for src/min_adaptglok.cpp: 17 added lines, 4 removed lines.
Original line number	Diff line number	Diff line
		@@ -92,6 +92,10 @@ int MinAdaptGlok::iterate(int maxiter)
		double *mass = atom->mass;
		int *type = atom->type;
		int nlocal = atom->nlocal;

		energy_force(0);
		neval++;

		dtf = 0.5 * dt * force->ftm2v;
		if (rmass) {
		for (int i = 0; i < nlocal; i++) {
		@@ -277,6 +281,10 @@ int MinAdaptGlok::iterate(int maxiter)
		}
		}

		eprevious = ecurrent;
		ecurrent = energy_force(0);
		neval++;


		// Velocity Verlet integration

		@@ -316,8 +324,9 @@ int MinAdaptGlok::iterate(int maxiter)
		}
		}

		double **f = atom->f;
		double **v = atom->v;
		eprevious = ecurrent;
		ecurrent = energy_force(0);
		neval++;

		if (rmass) {
		for (int i = 0; i < nlocal; i++) {
		@@ -373,6 +382,10 @@ int MinAdaptGlok::iterate(int maxiter)
		}
		}

		eprevious = ecurrent;
		ecurrent = energy_force(0);
		neval++;

		// Standard Euler integration

		}else if (integrator == 3) {
		@@ -411,12 +424,12 @@ int MinAdaptGlok::iterate(int maxiter)
		}
		}

		}

		eprevious = ecurrent;
		ecurrent = energy_force(0);
		neval++;

		}

		// energy tolerance criterion
		// only check after delaystep elapsed since velocties reset to 0
		// sync across replicas if running multi-replica minimization

Admin message