Move nan check from DriftModifierUNR to TWF

src/QMCDrivers/GreenFunctionModifiers/DriftModifierUNR.cpp

@@ -21,28 +21,12 @@ void DriftModifierUNR::getDrift(RealType tau, const GradType& qf, PosType& drift
 {
   // convert the complex WF gradient to real
   convertToReal(qf, drift);
-#ifndef NDEBUG
-  PosType debug_drift = drift;
-#endif
   RealType vsq = dot(drift, drift);
   RealType sc  = vsq < std::numeric_limits<RealType>::epsilon()
       ? tau
       : ((-1.0 + std::sqrt(1.0 + 2.0 * a_ * tau * vsq)) / (a_ * vsq));
   //Apply the umrigar scaling to drift.
   drift *= sc;
-  if (qmcplusplus::isnan(vsq))
-  {
-    std::ostringstream error_message;
-    for (int i = 0; i < drift.size(); ++i)
-    {
-      if (qmcplusplus::isnan(drift[i]))
-      {
-        error_message << "drift[" << i << "] is nan, vsq (" << vsq << ") sc (" << sc << ")\n";
-        break;
-      }
-    }
-    throw std::runtime_error(error_message.str());
-  }
 }
 
 void DriftModifierUNR::getDrift(RealType tau, const ComplexType& qf, ParticleSet::Scalar_t& drift) const
@@ -55,37 +39,20 @@ void DriftModifierUNR::getDrift(RealType tau, const ComplexType& qf, ParticleSet
       : ((-1.0 + std::sqrt(1.0 + 2.0 * a_ * tau * vsq)) / (a_ * vsq));
   //Apply the umrigar scaling to drift.
   drift *= sc;
-  if (qmcplusplus::isnan(vsq))
-  {
-    std::ostringstream error_message;
-    if (qmcplusplus::isnan(drift))
-    {
-      error_message << "drift is nan, vsq (" << vsq << ") sc (" << sc << ")\n";
-    }
-    else
-    {
-      error_message << "vsq is nan but drift is " << drift << ", unexpected, investigate.\n";
-    }
-    throw std::runtime_error(error_message.str());
-  }
 }
 
 void DriftModifierUNR::getDrifts(RealType tau, const std::vector<GradType>& qf, std::vector<PosType>& drift) const
 {
   for (int i = 0; i < qf.size(); ++i)
-  {
     getDrift(tau, qf[i], drift[i]);
-  }
 }
 
 void DriftModifierUNR::getDrifts(RealType tau,
                                  const std::vector<ComplexType>& qf,
                                  std::vector<ParticleSet::Scalar_t>& drift) const
 {
   for (int i = 0; i < qf.size(); ++i)
-  {
     getDrift(tau, qf[i], drift[i]);
-  }
 }
 
 bool DriftModifierUNR::parseXML(xmlNodePtr cur)

src/QMCDrivers/QMCDriverNew.h

@@ -433,12 +433,6 @@ class QMCDriverNew : public QMCDriverInterface, public MPIObjectBase
   ///a list of mcwalkerset element
   std::vector<xmlNodePtr> mcwalkerNodePtr;
 
-  ///temporary storage for drift
-  ParticleSet::ParticlePos drift;
-
-  ///temporary storage for random displacement
-  ParticleSet::ParticlePos deltaR;
-
   // ///alternate method of setting QMC run parameters
   // IndexType nStepsBetweenSamples;
   // ///samples per thread

src/QMCWaveFunctions/TrialWaveFunction.cpp

@@ -514,6 +514,7 @@ TrialWaveFunction::GradType TrialWaveFunction::evalGrad(ParticleSet& P, int iat)
     ScopedTimer z_timer(WFC_timers_[VGL_TIMER + TIMER_SKIP * i]);
     grad_iat += Z[i]->evalGrad(P, iat);
   }
+  checkOneParticleGradientsNaN(iat, grad_iat, "TWF::evalGrad");
   return grad_iat;
 }
 
@@ -527,6 +528,7 @@ TrialWaveFunction::GradType TrialWaveFunction::evalGradWithSpin(ParticleSet& P,
     ScopedTimer z_timer(WFC_timers_[VGL_TIMER + TIMER_SKIP * i]);
     grad_iat += Z[i]->evalGradWithSpin(P, iat, spingrad);
   }
+  checkOneParticleGradientsNaN(iat, grad_iat, "TWF::evalGradWithSpin");
   return grad_iat;
 }
 
@@ -553,6 +555,9 @@ void TrialWaveFunction::mw_evalGrad(const RefVectorWithLeader<TrialWaveFunction>
     wavefunction_components[i]->mw_evalGrad(wfc_list, p_list, iat, grads_z);
     grads += grads_z;
   }
+
+  for (const GradType& grads : grads.grads_positions)
+    checkOneParticleGradientsNaN(iat, grads, "TWF::mw_evalGrad");
 }
 
 // Evaluates the gradient w.r.t. to the source of the Laplacian
@@ -612,6 +617,8 @@ TrialWaveFunction::ValueType TrialWaveFunction::calcRatioGrad(ParticleSet& P, in
       ScopedTimer z_timer(WFC_timers_[VGL_TIMER + TIMER_SKIP * i]);
       r *= Z[i]->ratioGrad(P, iat, grad_iat);
     }
+
+  checkOneParticleGradientsNaN(iat, grad_iat, "TWF::calcRatioGrad");
   LogValueType logratio = convertValueToLog(r);
   PhaseDiff             = std::imag(logratio);
   return static_cast<ValueType>(r);
@@ -632,6 +639,7 @@ TrialWaveFunction::ValueType TrialWaveFunction::calcRatioGradWithSpin(ParticleSe
     r *= Z[i]->ratioGradWithSpin(P, iat, grad_iat, spingrad_iat);
   }
 
+  checkOneParticleGradientsNaN(iat, grad_iat, "TWF::calcRatioGradWithSpin");
   LogValueType logratio = convertValueToLog(r);
   PhaseDiff             = std::imag(logratio);
   return static_cast<ValueType>(r);
@@ -687,6 +695,9 @@ void TrialWaveFunction::mw_calcRatioGrad(const RefVectorWithLeader<TrialWaveFunc
   }
   for (int iw = 0; iw < wf_list.size(); iw++)
     wf_list[iw].PhaseDiff = std::imag(std::arg(ratios[iw]));
+
+  for (const GradType& grads : grad_new.grads_positions)
+    checkOneParticleGradientsNaN(iat, grads, "TWF::mw_calcRatioGrad");
 }
 
 void TrialWaveFunction::printGL(ParticleSet::ParticleGradient& G, ParticleSet::ParticleLaplacian& L, std::string tag)
@@ -1183,6 +1194,19 @@ void TrialWaveFunction::releaseResource(ResourceCollection& collection,
   }
 }
 
+void TrialWaveFunction::checkOneParticleGradientsNaN(int iel, const GradType& grads, const std::string_view location)
+{
+  if (qmcplusplus::isnan(std::norm(dot(grads, grads))))
+  {
+    std::ostringstream error_message;
+    error_message << "NaN check in " << location << " found" << std::endl;
+    for (int i = 0; i < grads.size(); ++i)
+      if (qmcplusplus::isnan(std::norm(grads[i])))
+        error_message << "  particle " << iel << " grads[" << i << "] is NaN." << std::endl;
+    throw std::runtime_error(error_message.str());
+  }
+}
+
 RefVectorWithLeader<WaveFunctionComponent> TrialWaveFunction::extractWFCRefList(
     const RefVectorWithLeader<TrialWaveFunction>& wf_list,
     int id)

src/QMCWaveFunctions/TrialWaveFunction.h

@@ -551,6 +551,13 @@ class TrialWaveFunction
   std::vector<std::reference_wrapper<NewTimer>> WFC_timers_;
   std::vector<RealType> myTwist;
 
+  /** check if any gradient component (x,y,z) is NaN and throw an error if yes.
+   * @param iel particle index
+   * @param grads gradients to be checked
+   * @param location usually put function name to indicate where the check is being called.
+   */
+  static void checkOneParticleGradientsNaN(int iel, const GradType& grads, const std::string_view location);
+
   /** @{
    *  @brief helper function for extracting a list of WaveFunctionComponent from a list of TrialWaveFunction
    */