library: add comm->procgrid to extract_global

python/lammps/core.py

@@ -891,7 +891,7 @@ class lammps(object):
     # set length of vector for items that are not a scalar
     vec_dict = { 'boxlo':3, 'boxhi':3, 'sublo':3, 'subhi':3,
                  'sublo_lambda':3, 'subhi_lambda':3, 'periodicity':3,
-                 'special_lj':4, 'special_coul':4 }
+                 'special_lj':4, 'special_coul':4, 'proc_grid':3 }
     if name in vec_dict:
       veclen = vec_dict[name]
     elif name == 'respa_dt':

python/lammps/pylammps.py

@@ -796,6 +796,7 @@ class PyLammps(object):
     comm = {}
     comm['nprocs'] = self.lmp.extract_setting("world_size")
     comm['nthreads'] = self.lmp.extract_setting("nthreads")
+    comm['proc_grid'] = self.lmp.extract_global("proc_grid")
 
     for line in output:
       if line.startswith("MPI library"):
@@ -804,8 +805,6 @@ class PyLammps(object):
         parts = self._split_values(line)
         comm['comm_style'] = self._get_pair(parts[0])[1]
         comm['comm_layout'] = self._get_pair(parts[1])[1]
-      elif line.startswith("Processor grid"):
-        comm['proc_grid'] = [int(x) for x in self._get_pair(line)[1].split('x')]
       elif line.startswith("Communicate velocities for ghost atoms"):
         comm['ghost_velocity'] = (self._get_pair(line)[1] == "yes")
     return comm

src/library.cpp

@@ -1386,6 +1386,7 @@ int lammps_extract_global_datatype(void * /*handle*/, const char *name)
   if (strcmp(name,"xy") == 0) return LAMMPS_DOUBLE;
   if (strcmp(name,"xz") == 0) return LAMMPS_DOUBLE;
   if (strcmp(name,"yz") == 0) return LAMMPS_DOUBLE;
+  if (strcmp(name,"proc_grid") == 0) return LAMMPS_INT;
 
   if (strcmp(name,"natoms") == 0) return LAMMPS_BIGINT;
   if (strcmp(name,"nbonds") == 0) return LAMMPS_BIGINT;
@@ -1604,6 +1605,10 @@ report the "native" data type.  The following tables are provided:
      - double
      - 1
      - triclinic tilt factor. See :doc:`Howto_triclinic`.
+   * - proc_grid
+     - int
+     - 3
+     - processor count assigned to each dimension of 3d grid. See :doc:`processors`.
 
 .. _extract_system_settings:
 
@@ -1861,6 +1866,10 @@ void *lammps_extract_global(void *handle, const char *name)
   if (strcmp(name,"xy") == 0) return (void *) &lmp->domain->xy;
   if (strcmp(name,"xz") == 0) return (void *) &lmp->domain->xz;
   if (strcmp(name,"yz") == 0) return (void *) &lmp->domain->yz;
+  if ((lmp->comm->layout == Comm::LAYOUT_UNIFORM ||
+       lmp->comm->layout == Comm::LAYOUT_NONUNIFORM) &&
+     (strcmp(name,"proc_grid") == 0))
+    return (void *) &lmp->comm->procgrid;
 
   if (strcmp(name,"natoms") == 0) return (void *) &lmp->atom->natoms;
   if (strcmp(name,"ntypes") == 0) return (void *) &lmp->atom->ntypes;