Changeset be729b for src/Dynamics

Timestamp:

Apr 10, 2018, 6:43:30 AM (7 years ago)

Author:

Frederik Heber <frederik.heber@…>

Branches:

AutomationFragmentation_failures, Candidate_v1.6.1, ChemicalSpaceEvaluator, Exclude_Hydrogens_annealWithBondGraph, ForceAnnealing_with_BondGraph, ForceAnnealing_with_BondGraph_contraction-expansion, Gui_displays_atomic_force_velocity, PythonUI_with_named_parameters, StoppableMakroAction, TremoloParser_IncreasedPrecision

Children:

038ccd

Parents:

6458e7

git-author:

Frederik Heber <frederik.heber@…> (06/27/17 21:13:13)

git-committer:

Frederik Heber <frederik.heber@…> (04/10/18 06:43:30)

Message:

ForceAnnealing::anneal() now only once reduces deltat.

• TESTFIX: Marked regression test ForceAnnealing (and redo) as XFAIL as we have removed storing the position update in the atomic velocities.
• TESTFIX: Marked Python tests on ForceAnnealing without bondgraph as XFAIL for the same reason.

File:

• src/Dynamics/ForceAnnealing.hpp (modified) (2 diffs)

src/Dynamics/ForceAnnealing.hpp

@@ -170 +170 @@
       Vector &maxComponents)
   {
+    bool deltat_decreased = false;
     for(typename AtomSetMixin<T>::iterator iter = AtomicForceManipulator<T>::atoms.begin();
         iter != AtomicForceManipulator<T>::atoms.end(); ++iter) {
@@ -193 +194 @@
         maxComponents[i] = std::max(maxComponents[i], fabs(currentGradient[i]));
 
-      // are we in initial step? Then don't check against velocity
-      if ((currentStep > 1) && (!(*iter)->getAtomicVelocity().IsZero()))
-        // update with currentDelta tells us how the current gradient relates to
-        // the last one: If it has become larger, reduce currentDelta
-        if ((PositionUpdate.ScalarProduct((*iter)->getAtomicVelocity()) < 0)
-            && (currentDeltat > MinimumDeltat)) {
-          currentDeltat = .5*currentDeltat;
-          LOG(2, "DEBUG: Upgrade in other direction: " << PositionUpdate.NormSquared()
-              << " > " << (*iter)->getAtomicVelocity().NormSquared()
-              << ", decreasing deltat: " << currentDeltat);
+      // steps may go back and forth again (updates are of same magnitude but
+      // have different sign: Check whether this is the case and one step with
+      // deltat to interrupt this sequence
+      const Vector PositionDifference = currentPosition - oldPosition;
+      if ((currentStep > 1) && (!PositionDifference.IsZero()))
+        if ((PositionUpdate.ScalarProduct(PositionDifference) < 0)
+            && (fabs(PositionUpdate.NormSquared()-PositionDifference.NormSquared()) < 1e-3)) {
+          // for convergence we want a null sequence here, too
+          if (!deltat_decreased) {
+            deltat_decreased = true;
+            currentDeltat = .5*currentDeltat;
+          }
+          LOG(2, "DEBUG: Upgrade in other direction: " << PositionUpdate
+              << " > " << PositionDifference
+              << ", using deltat: " << currentDeltat);
           PositionUpdate = currentDeltat * currentGradient;
       }
+
       // finally set new values
       (*iter)->setPosition(currentPosition + PositionUpdate);
-      (*iter)->setAtomicVelocity(PositionUpdate);
-      //std::cout << "Id of atom is " << (*iter)->getId() << std::endl;
-//        (*iter)->VelocityVerletUpdateU((*iter)->getId(), CurrentTimeStep-1, Deltat, IsAngstroem);
     }
   }