Merge pull request #3684 from jrgissing/encode_improper_symmetries

Encode improper symmetries

src/AMOEBA/improper_amoeba.cpp

@@ -36,6 +36,10 @@ using namespace MathConst;
 ImproperAmoeba::ImproperAmoeba(LAMMPS *lmp) : Improper(lmp)
 {
   writedata = 1;
+
+  // the second atom in the quadruplet is the atom of symmetry
+
+  symmatoms[1] = 1;
 }
 
 /* ---------------------------------------------------------------------- */

src/CLASS2/improper_class2.cpp

@@ -39,6 +39,10 @@ using namespace MathConst;
 ImproperClass2::ImproperClass2(LAMMPS *lmp) : Improper(lmp)
 {
   writedata = 1;
+
+  // the second atom in the quadruplet is the atom of symmetry
+
+  symmatoms[1] = 1;
 }
 
 /* ---------------------------------------------------------------------- */

src/EXTRA-MOLECULE/improper_cossq.cpp

@@ -37,7 +37,12 @@ using namespace MathConst;
 
 /* ---------------------------------------------------------------------- */
 
-ImproperCossq::ImproperCossq(LAMMPS *lmp) : Improper(lmp) {}
+ImproperCossq::ImproperCossq(LAMMPS *lmp) : Improper(lmp)
+{
+  // the first atom in the quadruplet is the atom of symmetry
+
+  symmatoms[0] = 1;
+}
 
 /* ---------------------------------------------------------------------- */
 

src/EXTRA-MOLECULE/improper_distance.cpp

@@ -35,7 +35,12 @@ using namespace LAMMPS_NS;
 
 /* ---------------------------------------------------------------------- */
 
-ImproperDistance::ImproperDistance(LAMMPS *lmp) : Improper(lmp) {}
+ImproperDistance::ImproperDistance(LAMMPS *lmp) : Improper(lmp)
+{
+  // the first atom in the quadruplet is the atom of symmetry
+
+  symmatoms[0] = 1;
+}
 
 /* ---------------------------------------------------------------------- */
 

src/EXTRA-MOLECULE/improper_fourier.cpp

@@ -35,7 +35,13 @@ using namespace LAMMPS_NS;
 
 /* ---------------------------------------------------------------------- */
 
-ImproperFourier::ImproperFourier(LAMMPS *lmp) : Improper(lmp) {}
+ImproperFourier::ImproperFourier(LAMMPS *lmp) : Improper(lmp)
+{
+  // the first and fourth atoms in the quadruplet are the atoms of symmetry
+
+  symmatoms[0] = 1;
+  symmatoms[3] = 2;
+}
 
 /* ---------------------------------------------------------------------- */
 

src/EXTRA-MOLECULE/improper_ring.cpp

@@ -59,7 +59,12 @@ using namespace MathSpecial;
 
 /* ---------------------------------------------------------------------- */
 
-ImproperRing::ImproperRing(LAMMPS *lmp) : Improper(lmp) {}
+ImproperRing::ImproperRing(LAMMPS *lmp) : Improper(lmp)
+{
+  // the second atom in the quadruplet is the atom of symmetry
+
+  symmatoms[1] = 1;
+}
 
 /* ---------------------------------------------------------------------- */
 

src/MOFFF/improper_inversion_harmonic.cpp

@@ -43,6 +43,10 @@ using namespace MathConst;
 ImproperInversionHarmonic::ImproperInversionHarmonic(LAMMPS *lmp) : Improper(lmp)
 {
   writedata = 1;
+
+  // the first atom in the quadruplet is the atom of symmetry
+
+  symmatoms[0] = 1;
 }
 
 /* ---------------------------------------------------------------------- */

src/MOLECULE/improper_cvff.cpp

@@ -32,6 +32,10 @@ static constexpr double SMALL = 0.001;
 ImproperCvff::ImproperCvff(LAMMPS *_lmp) : Improper(_lmp)
 {
   writedata = 1;
+
+  // the first atom in the quadruplet is the atom of symmetry
+
+  symmatoms[0] = 1;
 }
 
 /* ---------------------------------------------------------------------- */

src/MOLECULE/improper_harmonic.cpp

@@ -35,6 +35,10 @@ static constexpr double SMALL = 0.001;
 ImproperHarmonic::ImproperHarmonic(LAMMPS *_lmp) : Improper(_lmp)
 {
   writedata = 1;
+
+  // the first atom in the quadruplet is the atom of symmetry
+
+  symmatoms[0] = 1;
 }
 
 /* ---------------------------------------------------------------------- */

src/MOLECULE/improper_umbrella.cpp

@@ -39,6 +39,11 @@ static constexpr double SMALL = 0.001;
 ImproperUmbrella::ImproperUmbrella(LAMMPS *_lmp) : Improper(_lmp)
 {
   writedata = 1;
+
+  // the first and fourth atoms in the quadruplet are the atoms of symmetry
+
+  symmatoms[0] = 1;
+  symmatoms[3] = 2;
 }
 
 /* ---------------------------------------------------------------------- */

src/YAFF/improper_distharm.cpp

@@ -36,7 +36,12 @@ using namespace LAMMPS_NS;
 
 /* ---------------------------------------------------------------------- */
 
-ImproperDistHarm::ImproperDistHarm(LAMMPS *lmp) : Improper(lmp) {}
+ImproperDistHarm::ImproperDistHarm(LAMMPS *lmp) : Improper(lmp)
+{
+  // the fourth atom in the quadruplet is the atom of symmetry
+
+  symmatoms[3] = 1;
+}
 
 /* ---------------------------------------------------------------------- */
 

src/YAFF/improper_sqdistharm.cpp

@@ -36,7 +36,12 @@ using namespace LAMMPS_NS;
 
 /* ---------------------------------------------------------------------- */
 
-ImproperSQDistHarm::ImproperSQDistHarm(LAMMPS *lmp) : Improper(lmp) {}
+ImproperSQDistHarm::ImproperSQDistHarm(LAMMPS *lmp) : Improper(lmp)
+{
+  // the fourth atom in the quadruplet is the atom of symmetry
+
+  symmatoms[3] = 1;
+}
 
 /* ---------------------------------------------------------------------- */
 

src/improper.cpp

@@ -30,6 +30,7 @@ Improper::Improper(LAMMPS *_lmp) : Pointers(_lmp)
 {
   energy = 0.0;
   writedata = 0;
+  for (int i = 0; i < 4; i++) symmatoms[i] = 0;
 
   allocated = 0;
   suffix_flag = Suffix::NONE;

src/improper.h

@@ -36,6 +36,11 @@ class Improper : protected Pointers {
                              // CENTROID_SAME = same as two-body stress
                              // CENTROID_AVAIL = different and implemented
                              // CENTROID_NOTAVAIL = different, not yet implemented
+                             
+  int symmatoms[4];          // symmetry atom(s) of improper style
+                             // value of 0: interchangable atoms
+                             // value of 1: central atom
+                             // values >1: additional atoms of symmetry                             
 
   // KOKKOS host/device flag and data masks