Exemple #1
0
def RotateEvent(lep, jets, met_phi, phi):
    """Takes in LorentzVector lep, jets and rotates each along the Z axis by
    an angle phi
    @==========================================================
    @ Parameters
    lep: LorentzVector containing lepton information
    jets: Array of LorentzVectors containing jet information
    phi: Angle between 0 and 2 pi
    @==========================================================
    @ Return
    A rotated LorentzVector
    """
    # Missing Azimuthal Energy
    met_phi = TVector2.Phi_mpi_pi(met_phi + phi)

    # Lepton
    lep_new = TLorentzVector(lep)
    lep_new.RotateZ(phi)

    # Jets
    jets_new = []
    for j in jets:
        jets_new += [TLorentzVector(j)]
        j_new = jets_new[-1]
        j_new.btag = j.btag
        j_new.RotateZ(phi)

    return lep_new, jets_new, met_phi
Exemple #2
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def jet_processing(jet):
    # Find the jet (eta, phi)
    center=jet.sum(axis=0)
    v_jet=TLorentzVector(center[1], center[2], center[3], center[0])
    # Centering parameters
    phi=v_jet.Phi()
    bv = v_jet.BoostVector()
    bv.SetPerp(0)
    for n in np.arange(len(jet)):
        if np.sum(jet[n,:]) != 0:
            v = TLorentzVector(jet[n,1], jet[n,2], jet[n,3], jet[n,0])
            v.RotateZ(-phi)
            v.Boost(-bv)
            jet[n,:] = v[3], v[0], v[1], v[2] #(E,Px,Py,Pz)
    # Rotating parameters
    weighted_phi=0
    weighted_eta=0
    for n in np.arange(len(jet)):
        if np.sum(jet[n,:]) != 0:
            v = TLorentzVector(jet[n,1], jet[n,2], jet[n,3], jet[n,0])
            r = np.sqrt(v.Phi()**2 + v.Eta()**2)
            if r != 0: #in case there is only one component
                weighted_phi += v.Phi() * v.E()/r
                weighted_eta += v.Eta() * v.E()/r
    #alpha = np.arctan2(weighted_phi, weighted_eta) #approximately align at eta
    alpha = np.arctan2(weighted_eta, weighted_phi) #approximately align at phi
    for n in np.arange(len(jet)):
        if np.sum(jet[n,:]) != 0:
            v = TLorentzVector(jet[n,1], jet[n,2], jet[n,3], jet[n,0])
            #v.rotate_x(alpha) #approximately align at eta
            v.RotateX(-alpha) #approximately align at phi
            jet[n,:] = v[3], v[0], v[1], v[2] #(E,Px,Py,Pz)
    return jet