Merge branch 'halt2'

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

   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.

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

#include <math.h>

#include <stdlib.h>

#include <string.h>

#include "fix_halt.h"

#include "update.h"

#include "force.h"

#include "update.h"

#include "input.h"

#include "variable.h"

#include "atom.h"

#include "neighbor.h"

#include "modify.h"

#include "comm.h"

#include "timer.h"

#include "error.h"

using namespace LAMMPS_NS;

using namespace FixConst;

enum{BONDMAX,VARIABLE};

enum{LT,LE,GT,GE,EQ,NEQ,XOR};

enum{HARD,SOFT,CONTINUE};

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

FixHalt::FixHalt(LAMMPS *lmp, int narg, char **arg) :

  Fix(lmp, narg, arg), idvar(NULL)

{

  if (narg < 7) error->all(FLERR,"Illegal fix halt command");

  nevery = force->inumeric(FLERR,arg[3]);

  if (nevery <= 0) error->all(FLERR,"Illegal fix halt command");

  // comparison args

  idvar = NULL;

  if (strcmp(arg[4],"bondmax") == 0) attribute = BONDMAX;

  else if (strncmp(arg[4],"v_",2) == 0) {

    attribute = VARIABLE;

    int n = strlen(arg[4]);

    idvar = new char[n];

    strcpy(idvar,&arg[4][2]);

    ivar = input->variable->find(idvar);

    if (ivar < 0) error->all(FLERR,"Could not find fix halt variable name");

    if (input->variable->equalstyle(ivar) == 0)

      error->all(FLERR,"Fix halt variable is not equal-style variable");

  } else error->all(FLERR,"Invalid fix halt attribute");

  if (strcmp(arg[5],"<") == 0) operation = LT;

  else if (strcmp(arg[5],"<=") == 0) operation = LE;

  else if (strcmp(arg[5],">") == 0) operation = GT;

  else if (strcmp(arg[5],">=") == 0) operation = GE;

  else if (strcmp(arg[5],"==") == 0) operation = EQ;

  else if (strcmp(arg[5],"!=") == 0) operation = NEQ;

  else if (strcmp(arg[5],"|^") == 0) operation = XOR;

  else error->all(FLERR,"Invalid fix halt operator");

  value = force->numeric(FLERR,arg[6]);

  // parse optional args

  eflag = SOFT;

  int iarg = 7;

  while (iarg < narg) {

    if (strcmp(arg[iarg],"error") == 0) {

      if (iarg+2 > narg) error->all(FLERR,"Illegal fix halt command");

      if (strcmp(arg[iarg+1],"hard") == 0) eflag = HARD;

      else if (strcmp(arg[iarg+1],"soft") == 0) eflag = SOFT;

      else if (strcmp(arg[iarg+1],"continue") == 0) eflag = CONTINUE;

      else error->all(FLERR,"Illegal fix halt command");

      iarg += 2;

    } else error->all(FLERR,"Illegal fix halt command");

  }

  // add nfirst to all computes that store invocation times

  // since don't know a priori which are invoked via variables by this fix

  // once in end_of_step() can set timestep for ones actually invoked

  if (attribute == VARIABLE) {

    const bigint nfirst = (update->ntimestep/nevery)*nevery + nevery;

    modify->addstep_compute_all(nfirst);

  }

}

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

FixHalt::~FixHalt()

{

  delete [] idvar;

}

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

int FixHalt::setmask()

{

  int mask = 0;

  mask |= END_OF_STEP;

  mask |= POST_RUN;

  return mask;

}

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

void FixHalt::init()

{

  // set ivar from current variable list

  if (attribute == VARIABLE) {

    ivar = input->variable->find(idvar);

    if (ivar < 0) error->all(FLERR,"Could not find fix halt variable name");

    if (input->variable->equalstyle(ivar) == 0)

      error->all(FLERR,"Fix halt variable is not equal-style variable");

  }

}

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

void FixHalt::end_of_step()

{

  // variable evaluation may invoke computes so wrap with clear/add

  double attvalue;

  if (attribute == BONDMAX) attvalue = bondmax();

  else {

    modify->clearstep_compute();

    attvalue = input->variable->compute_equal(ivar);

    modify->addstep_compute(update->ntimestep + nevery);

  }

  // check if halt is triggered, else just return

  if (operation == LT) {

    if (attvalue >= value) return;

  } else if (operation == LE) {

    if (attvalue > value) return;

  } else if (operation == GT) {

    if (attvalue <= value) return;

  } else if (operation == GE) {

    if (attvalue < value) return;

  } else if (operation == EQ) {

    if (attvalue != value) return;

  } else if (operation == NEQ) {

    if (attvalue == value) return;

  } else if (operation == XOR) {

    if ((attvalue == 0.0 && value == 0.0) || 

        (attvalue != 0.0 && value != 0.0)) return;

  }

  // hard halt -> exit LAMMPS

  // soft/continue halt -> trigger timer to break from run loop

  // print message with ID of fix halt in case multiple instances

  char str[128];

  sprintf(str,"Fix halt %s condition met on step %ld with value %g",

          id,update->ntimestep,attvalue);

  if (eflag == HARD) error->all(FLERR,str);

  else if (eflag == SOFT || eflag == CONTINUE) {

    if (comm->me == 0) error->message(FLERR,str);

    timer->force_timeout();

  }

}

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

   reset expired timer setting to original value, if requested

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

void FixHalt::post_run()

{

  // continue halt -> subsequent runs are allowd

  if (eflag == CONTINUE) timer->reset_timeout();

}

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

   compute max length of any bond using Neighbor bondlist for each proc

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

double FixHalt::bondmax()

{

  double **x = atom->x;

  double **f = atom->f;

  int **bondlist = neighbor->bondlist;

  int nbondlist = neighbor->nbondlist;

  int nlocal = atom->nlocal;

  int i1,i2;

  double delx,dely,delz,rsq;

  double maxone = 0.0;

  for (int n = 0; n < nbondlist; n++) {

    i1 = bondlist[n][0];

    i2 = bondlist[n][1];

    delx = x[i1][0] - x[i2][0];

    dely = x[i1][1] - x[i2][1];

    delz = x[i1][2] - x[i2][2];

    rsq = delx*delx + dely*dely + delz*delz;

    maxone = MAX(rsq,maxone);

  }

  double maxall;

  MPI_Allreduce(&maxone,&maxall,1,MPI_DOUBLE,MPI_MAX,world);

  return sqrt(maxall);

}

/* -*- 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(halt,FixHalt)

#else

#ifndef LMP_FIX_HALT_H

#define LMP_FIX_HALT_H

#include <stdio.h>

#include "fix.h"

namespace LAMMPS_NS {

class FixHalt : public Fix {

 public:

  FixHalt(class LAMMPS *, int, char **);

  ~FixHalt();

  int setmask();

  void init();

  void end_of_step();

  void post_run();

 private:

  int attribute,operation,eflag,ivar;

  double attvalue,value;

  char *idvar;

  double bondmax();

};

}

#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: Cannot open fix print file %s

The output file generated by the fix print command cannot be opened

*/