Merge pull request #1716 from akohlmey/topology-interaction-check

Add topology interaction check to Force::init()

doc/src/Errors_warnings.txt

@@ -47,6 +47,11 @@ too far away. :dd
 
 Self-explanatory. :dd
 
+{Angles are defined but no angle style is set} :dt
+
+The topology contains angles, but there are no angle forces computed
+since there was no angle_style command. :dd
+
 {Atom style in data file differs from currently defined atom style} :dt
 
 Self-explanatory. :dd
@@ -73,6 +78,11 @@ short or the bond has blown apart and an atom is too far away. :dd
 
 Self-explanatory. :dd
 
+{Bonds are defined but no bond style is set} :dt
+
+The topology contains bonds, but there are no bond forces computed
+since there was no bond_style command. :dd
+
 {Bond/angle/dihedral extent > half of periodic box length} :dt
 
 This is a restriction because LAMMPS can be confused about which image
@@ -186,6 +196,11 @@ to check your simulation geometry. :dd
 
 Self-explanatory. :dd
 
+{Dihedrals are defined but no dihedral style is set} :dt
+
+The topology contains dihedrals, but there are no dihedral forces computed
+since there was no dihedral_style command. :dd
+
 {Dump dcd/xtc timestamp may be wrong with fix dt/reset} :dt
 
 If the fix changes the timestep, the dump dcd file will not
@@ -352,6 +367,11 @@ to check your simulation geometry. :dd
 
 Self-explanatory. :dd
 
+{Impropers are defined but no improper style is set} :dt
+
+The topology contains impropers, but there are no improper forces computed
+since there was no improper_style command. :dd
+
 {Inconsistent image flags} :dt
 
 The image flags for a pair on bonded atoms appear to be inconsistent.
@@ -407,6 +427,30 @@ This library function cannot be used if atom IDs are not defined or
 are not consecutively numbered, or if no atom map is defined.  See the
 atom_modify command for details about atom maps. :dd
 
+{Likewise 1-2 special neighbor interactions != 1.0} :dt
+
+The topology contains bonds, but there is no bond style defined
+and a 1-2 special neighbor scaling factor was not 1.0. This
+means that pair style interactions may have scaled or missing
+pairs in the neighbor list in expectation of interactions for
+those pairs being computed from the bond style. :dd
+
+{Likewise 1-3 special neighbor interactions != 1.0} :dt
+
+The topology contains angles, but there is no angle style defined
+and a 1-3 special neighbor scaling factor was not 1.0. This
+means that pair style interactions may have scaled or missing
+pairs in the neighbor list in expectation of interactions for
+those pairs being computed from the angle style. :dd
+
+{Likewise 1-4 special neighbor interactions != 1.0} :dt
+
+The topology contains dihedrals, but there is no dihedral style defined
+and a 1-4 special neighbor scaling factor was not 1.0. This
+means that pair style interactions may have scaled or missing
+pairs in the neighbor list in expectation of interactions for
+those pairs being computed from the dihedral style. :dd
+
 {Lost atoms via change_box: original %ld current %ld} :dt
 
 The command options you have used caused atoms to be lost. :dd

doc/src/min_spin.txt

@@ -17,8 +17,8 @@ min_style spin/lbfgs :pre
 
 [Examples:]
 
-min_style 	spin/lbfgs 
-min_modify      line spin_cubic discrete_factor 10.0 :pre
+min_style  spin/lbfgs
+min_modify line spin_cubic discrete_factor 10.0 :pre
 
 [Description:]
 

src/force.cpp

@@ -196,6 +196,28 @@ void Force::init()
   if (angle) angle->init();
   if (dihedral) dihedral->init();
   if (improper) improper->init();
+
+  // print warnings if topology and force field are inconsistent
+
+  if (comm->me == 0) {
+    if (!bond && (atom->nbonds > 0)) {
+      error->warning(FLERR,"Bonds are defined but no bond style is set");
+      if ((special_lj[1] != 1.0) || (special_coul[1] != 1.0))
+	error->warning(FLERR,"Likewise 1-2 special neighbor interactions != 1.0");
+    }
+    if (!angle && (atom->nangles > 0)) {
+      error->warning(FLERR,"Angles are defined but no angle style is set");
+      if ((special_lj[2] != 1.0) || (special_coul[2] != 1.0))
+	error->warning(FLERR,"Likewise 1-3 special neighbor interactions != 1.0");
+    }
+    if (!dihedral && (atom->ndihedrals > 0)) {
+      error->warning(FLERR,"Dihedrals are defined but no dihedral style is set");
+      if ((special_lj[3] != 1.0) || (special_coul[3] != 1.0))
+	error->warning(FLERR,"Likewise 1-4 special neighbor interactions != 1.0");
+    }
+    if (!improper && (atom->nimpropers > 0))
+      error->warning(FLERR,"Impropers are defined but no improper style is set");
+  }
 }
 
 /* ---------------------------------------------------------------------- */

src/force.h

@@ -226,4 +226,48 @@ A command with an argument that specifies an integer or range of
 integers is using a value that is less than 1 or greater than the
 maximum allowed limit.
 
+W: Bonds are defined but no bond style is set
+
+The topology contains bonds, but there are no bond forces computed
+since there was no bond_style command.
+
+W: Angles are defined but no angle style is set
+
+The topology contains angles, but there are no angle forces computed
+since there was no angle_style command.
+
+W: Dihedrals are defined but no dihedral style is set
+
+The topology contains dihedrals, but there are no dihedral forces computed
+since there was no dihedral_style command.
+
+W: Impropers are defined but no improper style is set
+
+The topology contains impropers, but there are no improper forces computed
+since there was no improper_style command.
+
+W: Likewise 1-2 special neighbor interactions != 1.0
+
+The topology contains bonds, but there is no bond style defined
+and a 1-2 special neighbor scaling factor was not 1.0. This
+means that pair style interactions may have scaled or missing
+pairs in the neighbor list in expectation of interactions for
+those pairs being computed from the bond style.
+
+W: Likewise 1-3 special neighbor interactions != 1.0
+
+The topology contains angles, but there is no angle style defined
+and a 1-3 special neighbor scaling factor was not 1.0. This
+means that pair style interactions may have scaled or missing
+pairs in the neighbor list in expectation of interactions for
+those pairs being computed from the angle style.
+
+W: Likewise 1-4 special neighbor interactions != 1.0
+
+The topology contains dihedrals, but there is no dihedral style defined
+and a 1-4 special neighbor scaling factor was not 1.0. This
+means that pair style interactions may have scaled or missing
+pairs in the neighbor list in expectation of interactions for
+those pairs being computed from the dihedral style.
+
 */