double Qjets::ComputeNormalization(double dmin){
double norm(0.);
for(list<jet_distance>::iterator it = _distances.begin(); it != _distances.end(); )
if(JetsUnmerged(*it)){
double inc = 0.;
/*
We need to be careful about dmin == 0 which happens for collinear jets.
(Thanks go to Nhan V Tran for finding this bug)
*/
if(dmin == 0.){
if((*it).dij == 0.)
inc = 1.;
else
inc = 0.;
} else
inc = exp(-_rigidity*((*it).dij-dmin)/dmin);
assert(inc <= 1. && !isnan((float) inc));
norm += inc;
it++;
} else
it = _distances.erase(it);
return norm;
}
jet_distance Qjets::GetNextDistance(){
vector< pair<jet_distance, double> > popped_distances;
double norm(0.);
jet_distance ret;
ret.j1 = -1;
ret.j2 = -1;
ret.dij = -1.;
bool dmin_set(false);
double dmin(0.);
while(!_distances.empty()){
jet_distance dist = _distances.top();
_distances.pop();
if(JetsUnmerged(dist)){
if(!dmin_set){
dmin = dist.dij;
dmin_set = true;
}
double weight = exp(-_rigidity * (dist.dij-dmin) /dmin);
popped_distances.push_back(make_pair(dist,weight));
norm += weight;
if(weight/norm < _truncation_fctr)
break;
}
}
double rand(Rand()), tot_weight(0.);
for(vector<pair<jet_distance, double> >::iterator it = popped_distances.begin(); it != popped_distances.end(); it++){
tot_weight += (*it).second/norm;
if(tot_weight >= rand){
ret = (*it).first;
break;
}
}
// repopulate in reverse (maybe quicker?)
for(vector<pair<jet_distance, double> >::reverse_iterator it = popped_distances.rbegin(); it != popped_distances.rend(); it++)
if(JetsUnmerged((*it).first))
_distances.push((*it).first);
return ret;
}
double Qjets::ComputeMinimumDistance(){
double dmin(-1.);
for(list<jet_distance>::iterator it = _distances.begin(); it != _distances.end(); )
if(JetsUnmerged(*it)){
if(dmin == -1. || (*it).dij < dmin)
dmin = (*it).dij;
it++;
} else
it = _distances.erase(it);
return dmin;
}
double Qjets::ComputeNormalization(double dmin) {
double norm(0.);
for(list<jet_distance>::iterator it = _distances.begin(); it != _distances.end(); )
if(JetsUnmerged(*it)) {
double inc = exp(-_rigidity*((*it).dij-dmin)/dmin);
// assert(inc <= 1. && !std::isnan(inc));
// assert(inc <= 1);
if (!( inc <= 1.)) {
std::cout << "_rigidity: " << _rigidity << std::endl;
std::cout << "(*it).dij: " << (*it).dij << std::endl;
std::cout << "dmin: " << dmin << std::endl;
std::cout << "-_rigidity*((*it).dij-dmin)/dmin: " << -_rigidity*((*it).dij-dmin)/dmin << std::endl;
std::cout << "exp(-_rigidity*((*it).dij-dmin)/dmin): " << exp(-_rigidity*((*it).dij-dmin)/dmin) << std::endl;
assert(inc <= 1.);
}
assert(!std::isnan(inc));
norm += inc;
it++;
} else
it = _distances.erase(it);
return norm;
}