git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@4905 f3b2605a-c512-4ea7-a41b-209d697bcdaa

src/REPLICA/fix_event.cpp

@@ -0,0 +1,251 @@
+/* ----------------------------------------------------------------------
+   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.
+------------------------------------------------------------------------- */
+
+/* ----------------------------------------------------------------------
+   Contributing author: Mike Brown (SNL)
+------------------------------------------------------------------------- */
+
+#include "stdlib.h"
+#include "string.h"
+#include "fix_event.h"
+#include "atom.h"
+#include "update.h"
+#include "domain.h"
+#include "neighbor.h"
+#include "comm.h"
+#include "universe.h"
+#include "memory.h"
+#include "error.h"
+
+using namespace LAMMPS_NS;
+
+/* ---------------------------------------------------------------------- */
+
+FixEvent::FixEvent(LAMMPS *lmp, int narg, char **arg) :
+  Fix(lmp, narg, arg)
+{
+  if (narg != 3) error->all("Illegal fix event command");
+
+  restart_global = 1;
+
+  // perform initial allocation of atom-based array
+  // register with Atom class
+
+  xevent = NULL;
+  xold = NULL;
+  imageold = NULL;
+  grow_arrays(atom->nmax);
+  atom->add_callback(0);
+
+  event_number = 0;
+  event_timestep = update->ntimestep;
+  clock = 0;
+}
+
+/* ---------------------------------------------------------------------- */
+
+FixEvent::~FixEvent()
+{
+  // unregister callbacks to this fix from Atom class
+ 
+  atom->delete_callback(id,0);
+
+  // delete locally stored array
+
+  memory->destroy_2d_double_array(xevent);
+  memory->destroy_2d_double_array(xold);
+  memory->sfree(imageold);
+}
+
+/* ---------------------------------------------------------------------- */
+
+int FixEvent::setmask()
+{
+  return 0;
+}
+
+/* ----------------------------------------------------------------------
+   save current atom coords as an event
+   called when an event occurs in some replica
+   set event_timestep = when event occurred in a particular replica
+   update clock = elapsed time since last event, across all replicas
+------------------------------------------------------------------------- */
+
+void FixEvent::store_event(int timestep, int delta_clock)
+{
+  double **x = atom->x;
+  int *image = atom->image;
+  int nlocal = atom->nlocal;
+
+  for (int i = 0; i < nlocal; i++) 
+    domain->unmap(x[i],image[i],xevent[i]);
+
+  event_timestep = timestep;
+  clock += delta_clock;
+  event_number++;
+}
+
+/* ----------------------------------------------------------------------
+   store state of all atoms
+   called before quench and subsequent check for event
+   so can later restore pre-quench state if no event occurs
+------------------------------------------------------------------------- */
+
+void FixEvent::store_state()
+{
+  double **x = atom->x;
+  double **f = atom->f;
+  int *image = atom->image;
+  int nlocal = atom->nlocal;
+
+  for (int i = 0; i < nlocal; i++) {
+    xold[i][0] = x[i][0];
+    xold[i][1] = x[i][1];
+    xold[i][2] = x[i][2];
+    imageold[i] = image[i];
+  }
+}
+
+/* ----------------------------------------------------------------------
+   restore state of all atoms to pre-quench state
+   called after no event detected so can continue
+------------------------------------------------------------------------- */
+
+void FixEvent::restore_state()
+{
+  double **x = atom->x;
+  int *image = atom->image;
+  int nlocal = atom->nlocal;
+
+  for (int i = 0; i < nlocal; i++) {
+    x[i][0] = xold[i][0];
+    x[i][1] = xold[i][1];
+    x[i][2] = xold[i][2];
+    image[i] = imageold[i];
+  }
+}
+
+/* ----------------------------------------------------------------------
+   memory usage of local atom-based array
+------------------------------------------------------------------------- */
+
+double FixEvent::memory_usage()
+{
+  double bytes = 6*atom->nmax * sizeof(double);
+  bytes += atom->nmax*sizeof(int);
+  return bytes;
+}
+
+/* ----------------------------------------------------------------------
+   allocate atom-based array
+------------------------------------------------------------------------- */
+
+void FixEvent::grow_arrays(int nmax)
+{
+  xevent = memory->grow_2d_double_array(xevent,nmax,3,"event:xevent");
+  xold = memory->grow_2d_double_array(xold,nmax,3,"event:xold");
+  imageold = (int *) 
+    memory->srealloc(imageold,nmax*sizeof(int),"event:imageold");
+
+  // allow compute event to access stored event coords
+
+  array_atom = xevent;
+}
+
+/* ----------------------------------------------------------------------
+   copy values within local atom-based array
+------------------------------------------------------------------------- */
+
+void FixEvent::copy_arrays(int i, int j)
+{
+  xevent[j][0] = xevent[i][0];
+  xevent[j][1] = xevent[i][1];
+  xevent[j][2] = xevent[i][2];
+  xold[j][0] = xold[i][0];
+  xold[j][1] = xold[i][1];
+  xold[j][2] = xold[i][2];
+  imageold[j] = imageold[i];
+}
+
+/* ----------------------------------------------------------------------
+   pack values in local atom-based array for exchange with another proc
+------------------------------------------------------------------------- */
+
+int FixEvent::pack_exchange(int i, double *buf)
+{
+  buf[0] = xevent[i][0];
+  buf[1] = xevent[i][1];
+  buf[2] = xevent[i][2];
+  buf[3] = xold[i][0];
+  buf[4] = xold[i][1];
+  buf[5] = xold[i][2];
+  buf[6] = imageold[i];
+
+  return 7;
+}
+
+/* ----------------------------------------------------------------------
+   unpack values in local atom-based array from exchange with another proc
+------------------------------------------------------------------------- */
+
+int FixEvent::unpack_exchange(int nlocal, double *buf)
+{
+  xevent[nlocal][0] = buf[0];
+  xevent[nlocal][1] = buf[1];
+  xevent[nlocal][2] = buf[2];
+  xold[nlocal][0] = buf[3];
+  xold[nlocal][1] = buf[4];
+  xold[nlocal][2] = buf[5];
+  imageold[nlocal] = static_cast<int>(buf[6]);
+
+  return 7;
+}
+
+/* ----------------------------------------------------------------------
+   pack entire state of Fix into one write 
+------------------------------------------------------------------------- */
+
+void FixEvent::write_restart(FILE *fp)
+{
+  int n = 0;
+  double list[5];
+  list[n++] = event_number;
+  list[n++] = event_timestep;
+  list[n++] = clock;
+  list[n++] = replica_number;
+  list[n++] = correlated_event;
+  list[n++] = ncoincident;
+
+  if (comm->me == 0) {
+    int size = n * sizeof(double);
+    fwrite(&size,sizeof(int),1,fp);
+    fwrite(list,sizeof(double),n,fp);
+  }
+}
+
+/* ----------------------------------------------------------------------
+   use state info from restart file to restart the Fix 
+------------------------------------------------------------------------- */
+
+void FixEvent::restart(char *buf)
+{
+  int n = 0;
+  double *list = (double *) buf;
+
+  event_number = static_cast<int> (list[n++]);
+  event_timestep = static_cast<int> (list[n++]);
+  clock = static_cast<int> (list[n++]);
+  replica_number = static_cast<int> (list[n++]);
+  correlated_event = static_cast<int> (list[n++]);
+  ncoincident = static_cast<int> (list[n++]);
+}