added bondmax method to fix halt

   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 "variable.h"

#include "error.h"

using namespace LAMMPS_NS;

enum{BONDMAX,VARIABLE};

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

enum{SOFT,HARD};

enum{HARD,SOFT,CONTINUE};

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

  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],"soft") == 0) eflag = SOFT;

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

      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");

{

  // 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()

{

  // make a copy of string to work on

  // substitute for $ variables (no printing)

  // append a newline and print final copy

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

  double attvalue;

  }

  // hard halt -> exit LAMMPS

  // also print ID of fix halt in case multiple ?

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

  // continue halt -> trigger time to exit only this 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,"Fix halt condition triggered");

  else { // eflag == SOFT

    if (comm->me == 0) error->message(FLERR,"Fix halt condition triggered");

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

  else if (eflag == SOFT) {

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

    timer->force_timeout();

  } else if (eflag == CONTINUE) {

    // exit this run, but not subsequent ones

  }

}

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

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

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

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

double FixHalt::bondmax()

{

  // could add custom keyword methods

  // e.g. one to compute max bond length, with no sqrt()

  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 0.0;

  return sqrt(maxall);

}