introduced a pseudo-random sign of the phi shift

cms-sw · Jun 13, 2015 · 2c753b3 · 2c753b3
1 parent a88380d
commit 2c753b3
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Showing 2 changed files with 4 additions and 2 deletions.
diff --git a/DataFormats/PatCandidates/src/PackedCandidate.cc b/DataFormats/PatCandidates/src/PackedCandidate.cc
@@ -63,7 +63,8 @@ void pat::PackedCandidate::packVtx(bool unpackAfterwards) {
 void pat::PackedCandidate::unpack() const {
     float pt = MiniFloatConverter::float16to32(packedPt_);
     double shift = (pt<1. ? 0.1*pt : 0.1/pt); // shift particle phi to break degeneracies in angular separations
-    double phi = int16_t(packedPhi_)*3.2f/std::numeric_limits<int16_t>::max() + shift*3.2/std::numeric_limits<int16_t>::max();
+    double sign = ( ( int(pt*10) % 2 == 0 ) ? 1 : -1 ); // introduce a pseudo-random sign of the shift
+    double phi = int16_t(packedPhi_)*3.2f/std::numeric_limits<int16_t>::max() + sign*shift*3.2/std::numeric_limits<int16_t>::max();
     p4_ = PolarLorentzVector(pt,
                              int16_t(packedEta_)*6.0f/std::numeric_limits<int16_t>::max(),
                              phi,

diff --git a/DataFormats/PatCandidates/src/PackedGenParticle.cc b/DataFormats/PatCandidates/src/PackedGenParticle.cc
@@ -20,7 +20,8 @@ void pat::PackedGenParticle::unpack() const {
     float pz = std::tanh(y)*std::sqrt((m*m+pt*pt)/(1.-std::tanh(y)*std::tanh(y)));
     float eta = std::asinh(pz/pt);
     double shift = (pt<1. ? 0.1*pt : 0.1/pt); // shift particle phi to break degeneracies in angular separations
-    double phi = int16_t(packedPhi_)*3.2f/std::numeric_limits<int16_t>::max() + shift*3.2/std::numeric_limits<int16_t>::max();
+    double sign = ( ( int(pt*10) % 2 == 0 ) ? 1 : -1 ); // introduce a pseudo-random sign of the shift
+    double phi = int16_t(packedPhi_)*3.2f/std::numeric_limits<int16_t>::max() + sign*shift*3.2/std::numeric_limits<int16_t>::max();
     p4_ = PolarLorentzVector(pt,eta,phi,m);
     p4c_ = p4_;
     unpacked_ = true;