Table of Contents

tutorials

useful stuff

teaching and seminars

Code

Sorting a vector based on another vector: http://stackoverflow.com/questions/236172/how-do-i-sort-a-stdvector-by-the-values-of-a-different-stdvector

struct tlvordering {
	bool operator ()(std::pair<size_t, std::vector<TLorentzVector>::const_iterator> const& a, std::pair<size_t, std::vector<TLorentzVector>::const_iterator> const& b) {
		return (*(a.second)).Pt() > (b.second->Pt());
	}
};


template <typename T>
std::vector<T> sort_from_tlvref(
		std::vector<T> const& in,
		std::vector<std::pair<size_t, std::vector<TLorentzVector>::const_iterator> > const& reference
) {
		std::vector<T> ret(in.size());

		size_t const size = in.size();
		for (size_t i = 0; i < size; ++i)
				ret[i] = in[reference[i].first];

		return ret;
}


void sortJetsByPt(std::vector<unsigned int>& selJets, // index vector
					std::vector<TLorentzVector>& selJetsP4,
					std::vector<int>& selJetsSVMassBins,
					std::vector<double>& selJetsSVMassSum,
					std::vector< std::vector<bool> >& selJetsBTags,
					std::vector<JetFlavor::Code>& selJetsFlav) {

	// make a pair of index order and TLorentzVector
	std::vector<std::pair<size_t, std::vector<TLorentzVector>::const_iterator> > order(selJetsP4.size());
	size_t n = 0;
	for (std::vector<TLorentzVector>::const_iterator it = selJetsP4.begin(); it != selJetsP4.end(); ++it, ++n) {
		order[n] = std::make_pair(n, it);
	}
	// sort order pair by jet Pt
	sort(order.begin(), order.end(), tlvordering());
	// user order pair as reference for sorting all vectors
	selJets = sort_from_tlvref(selJets, order);
	selJetsP4 = sort_from_tlvref(selJetsP4, order);
	selJetsSVMassBins = sort_from_tlvref(selJetsSVMassBins, order);
	selJetsSVMassSum = sort_from_tlvref(selJetsSVMassSum, order);
	selJetsBTags = sort_from_tlvref(selJetsBTags, order);
	selJetsFlav = sort_from_tlvref(selJetsFlav, order);

	// loop over jets and change order
//   for (size_t iJ = 0; iJ < selJets.size()-1; ++iJ) {
//     
//     if (selJetsP4[iJ].Pt() < selJetsP4[iJ+1].Pt()) {
//       jetOrder[iJ] = iJ+1
//     }
//   }

}