File indexing completed on 2024-04-06 12:18:23
0001 #ifndef JET_JETUTIL_H
0002 #define JET_JETUTIL_H 1
0003
0004 #include <cmath>
0005 #include <algorithm>
0006
0007 class PtGreater {
0008 public:
0009 template <typename T>
0010 bool operator()(const T& i, const T& j) {
0011 return (i.pt() > j.pt());
0012 }
0013 };
0014
0015 class EtGreater {
0016 public:
0017 template <typename T>
0018 bool operator()(const T& i, const T& j) {
0019 return (i.et() > j.et());
0020 }
0021 };
0022
0023 class JetUtil {
0024 public:
0025 static double Phi_0_2pi(double x) {
0026 while (x >= 2 * M_PI)
0027 x -= 2 * M_PI;
0028 while (x < 0.)
0029 x += 2 * M_PI;
0030 return x;
0031 }
0032
0033 static double Phi_mpi_pi(double x) {
0034 while (x >= M_PI)
0035 x -= 2 * M_PI;
0036 while (x < -M_PI)
0037 x += 2 * M_PI;
0038 return x;
0039 }
0040
0041 static double dPhi(double phi1, double phi2) {
0042 phi1 = Phi_0_2pi(phi1);
0043 phi2 = Phi_0_2pi(phi2);
0044 return Phi_mpi_pi(phi1 - phi2);
0045 }
0046
0047 static double radius(double eta1, double phi1, double eta2, double phi2) {
0048 const double TWOPI = 2.0 * M_PI;
0049
0050 phi1 = Phi_0_2pi(phi1);
0051 phi2 = Phi_0_2pi(phi2);
0052
0053 double dphi = Phi_0_2pi(phi1 - phi2);
0054 dphi = std::min(dphi, TWOPI - dphi);
0055 double deta = eta1 - eta2;
0056
0057 return sqrt(deta * deta + dphi * dphi);
0058 }
0059
0060 template <typename T1, typename T2>
0061 static double radius(const T1& t1, const T2& t2) {
0062 return radius(t1->eta(), t1->phi(), t2->eta(), t2->phi());
0063 }
0064 };
0065 #endif
