Example #1
0
// calculator
void CoordinationBase::calculate()
{

 double ncoord=0.;
 Tensor virial;
 vector<Vector> deriv(getNumberOfAtoms());
// deriv.resize(getPositions().size());

 if(nl->getStride()>0 && invalidateList){
   nl->update(getPositions());
 }

 unsigned stride=comm.Get_size();
 unsigned rank=comm.Get_rank();
 if(serial){
   stride=1;
   rank=0;
 }else{
   stride=comm.Get_size();
   rank=comm.Get_rank();
 }

 for(unsigned int i=rank;i<nl->size();i+=stride) {                   // sum over close pairs
 
  Vector distance;
  unsigned i0=nl->getClosePair(i).first;
  unsigned i1=nl->getClosePair(i).second;

  if(getAbsoluteIndex(i0)==getAbsoluteIndex(i1)) continue;

  if(pbc){
   distance=pbcDistance(getPosition(i0),getPosition(i1));
  } else {
   distance=delta(getPosition(i0),getPosition(i1));
  }

  double dfunc=0.;
  ncoord += pairing(distance.modulo2(), dfunc,i0,i1);

  deriv[i0] = deriv[i0] + (-dfunc)*distance ;
  deriv[i1] = deriv[i1] + dfunc*distance ;
  virial=virial+(-dfunc)*Tensor(distance,distance);
 }

 if(!serial){
   comm.Sum(ncoord);
   if(!deriv.empty()) comm.Sum(&deriv[0][0],3*deriv.size());
   comm.Sum(virial);
 }

 for(unsigned i=0;i<deriv.size();++i) setAtomsDerivatives(i,deriv[i]);
 setValue           (ncoord);
 setBoxDerivatives  (virial);

}
Example #2
0
// calculator
void CoordinationBase::calculate()
{

  double ncoord=0.;
  Tensor virial;
  vector<Vector> deriv(getNumberOfAtoms());
// deriv.resize(getPositions().size());

  if(nl->getStride()>0 && invalidateList) {
    nl->update(getPositions());
  }

  unsigned stride=comm.Get_size();
  unsigned rank=comm.Get_rank();
  if(serial) {
    stride=1;
    rank=0;
  } else {
    stride=comm.Get_size();
    rank=comm.Get_rank();
  }

  unsigned nt=OpenMP::getNumThreads();

  const unsigned nn=nl->size();

  if(nt*stride*10>nn) nt=nn/stride/10;
  if(nt==0)nt=1;

  #pragma omp parallel num_threads(nt)
  {
    std::vector<Vector> omp_deriv(getPositions().size());
    Tensor omp_virial;

    #pragma omp for reduction(+:ncoord) nowait
    for(unsigned int i=rank; i<nn; i+=stride) {

      Vector distance;
      unsigned i0=nl->getClosePair(i).first;
      unsigned i1=nl->getClosePair(i).second;

      if(getAbsoluteIndex(i0)==getAbsoluteIndex(i1)) continue;

      if(pbc) {
        distance=pbcDistance(getPosition(i0),getPosition(i1));
      } else {
        distance=delta(getPosition(i0),getPosition(i1));
      }

      double dfunc=0.;
      ncoord += pairing(distance.modulo2(), dfunc,i0,i1);

      Vector dd(dfunc*distance);
      Tensor vv(dd,distance);
      if(nt>1) {
        omp_deriv[i0]-=dd;
        omp_deriv[i1]+=dd;
        omp_virial-=vv;
      } else {
        deriv[i0]-=dd;
        deriv[i1]+=dd;
        virial-=vv;
      }

    }
    #pragma omp critical
    if(nt>1) {
      for(int i=0; i<getPositions().size(); i++) deriv[i]+=omp_deriv[i];
      virial+=omp_virial;
    }
  }

  if(!serial) {
    comm.Sum(ncoord);
    if(!deriv.empty()) comm.Sum(&deriv[0][0],3*deriv.size());
    comm.Sum(virial);
  }

  for(unsigned i=0; i<deriv.size(); ++i) setAtomsDerivatives(i,deriv[i]);
  setValue           (ncoord);
  setBoxDerivatives  (virial);

}
Example #3
0
void PathMSDBase::calculate(){

  if(neigh_size>0 && getExchangeStep()) error("Neighbor lists for this collective variable are not compatible with replica exchange, sorry for that!");

  //log.printf("NOW CALCULATE! \n");


  // resize the list to full
  if(imgVec.empty()){ // this is the signal that means: recalculate all 
      imgVec.resize(nframes);  
      for(unsigned i=0;i<nframes;i++){
          imgVec[i].property=indexvec[i];
          imgVec[i].index=i;
      }
  }

// THIS IS THE HEAVY PART (RMSD STUFF)
  unsigned stride=comm.Get_size();
  unsigned rank=comm.Get_rank();
  unsigned nat=pdbv[0].size();
  plumed_assert(nat>0);
  plumed_assert(nframes>0);
  plumed_assert(imgVec.size()>0);

  std::vector<double> tmp_distances(imgVec.size(),0.0);
  std::vector<Vector> tmp_derivs;
// this array is a merge of all tmp_derivs, so as to allow a single comm.Sum below
  std::vector<Vector> tmp_derivs2(imgVec.size()*nat);

// if imgVec.size() is less than nframes, it means that only some msd will be calculated
  for(unsigned i=rank;i<imgVec.size();i+=stride){
// store temporary local results
    tmp_distances[i]=msdv[imgVec[i].index].calculate(getPositions(),tmp_derivs,true);
    plumed_assert(tmp_derivs.size()==nat);
    for(unsigned j=0;j<nat;j++) tmp_derivs2[i*nat+j]=tmp_derivs[j];
  }
// reduce over all processors
  comm.Sum(tmp_distances);
  comm.Sum(tmp_derivs2);
// assign imgVec[i].distance and imgVec[i].distder
  for(unsigned i=0;i<imgVec.size();i++){
    imgVec[i].distance=tmp_distances[i];
    imgVec[i].distder.assign(&tmp_derivs2[i*nat],nat+&tmp_derivs2[i*nat]);
  }

// END OF THE HEAVY PART

  vector<Value*> val_s_path;
  if(labels.size()>0){
    for(unsigned i=0;i<labels.size();i++){ val_s_path.push_back(getPntrToComponent(labels[i].c_str()));}
  }else{
     val_s_path.push_back(getPntrToComponent("sss"));
  } 
  Value* val_z_path=getPntrToComponent("zzz");

  vector<double> s_path(val_s_path.size());for(unsigned i=0;i<s_path.size();i++)s_path[i]=0.;
  double partition=0.;
  double tmp;

  // clean vector
  for(unsigned i=0;i< derivs_z.size();i++){derivs_z[i].zero();}

  typedef  vector< class ImagePath  >::iterator imgiter;
  for(imgiter it=imgVec.begin();it!=imgVec.end();++it){ 
    (*it).similarity=exp(-lambda*((*it).distance));
    //log<<"DISTANCE "<<(*it).distance<<"\n";
    for(unsigned i=0;i<s_path.size();i++){
   	 s_path[i]+=((*it).property[i])*(*it).similarity;
    }
    partition+=(*it).similarity;
  }
  for(unsigned i=0;i<s_path.size();i++){ s_path[i]/=partition;  val_s_path[i]->set(s_path[i]) ;}
  val_z_path->set(-(1./lambda)*std::log(partition));
  for(unsigned j=0;j<s_path.size();j++){
    // clean up
    for(unsigned i=0;i< derivs_s.size();i++){derivs_s[i].zero();}
    // do the derivative 
    for(imgiter it=imgVec.begin();it!=imgVec.end();++it){ 
       double expval=(*it).similarity;
       tmp=lambda*expval*(s_path[j]-(*it).property[j])/partition;
       for(unsigned i=0;i< derivs_s.size();i++){ derivs_s[i]+=tmp*(*it).distder[i] ;} 
       if(j==0){for(unsigned i=0;i< derivs_z.size();i++){ derivs_z[i]+=(*it).distder[i]*expval/partition;}} 
    }
    for(unsigned i=0;i< derivs_s.size();i++){
          setAtomsDerivatives (val_s_path[j],i,derivs_s[i]); 
          if(j==0){setAtomsDerivatives (val_z_path,i,derivs_z[i]);} 
    }
  }
  for(unsigned i=0;i<val_s_path.size();++i) setBoxDerivativesNoPbc(val_s_path[i]);
  setBoxDerivativesNoPbc(val_z_path);
  //
  //  here set next round neighbors
  //
  if (neigh_size>0){
	//if( int(getStep())%int(neigh_stride/getTimeStep())==0 ){
	// enforce consistency: the stride is in time steps
	if( int(getStep())%int(neigh_stride)==0 ){

		// next round do it all:empty the vector	
		imgVec.clear();
        }
        // time to analyze the results: 
        if(imgVec.size()==nframes){
            //sort by msd
            sort(imgVec.begin(), imgVec.end(), imgOrderByDist()); 
            //resize
            imgVec.resize(neigh_size);
        } 
  }
  //log.printf("CALCULATION DONE! \n");
}