PackedTrack now preserves sign of q/p when converting to q times p

Event/EventPacker/src/lib/PackedTrack.cpp

@@ -103,8 +103,10 @@ void TrackPacker::convertState( const LHCb::State& state, PackedDataVector& ptra
   newState.z    = StandardPacker::position( state.z() );
   newState.tx   = StandardPacker::slope( state.tx() );
   newState.ty   = StandardPacker::slope( state.ty() );
-  const auto qp = std::abs( state.qOverP() ) < TrackParameters::lowTolerance ? 0. : 1. / state.qOverP();
-  newState.p    = StandardPacker::energy( qp );
+  const auto qp = std::isfinite( 1. / state.qOverP() )
+                      ? 1. / state.qOverP()
+                      : std::copysign( std::numeric_limits<double>::max(), state.qOverP() );
+  newState.p = StandardPacker::energy( qp );
   //== Get the coded value in case of saturation, to code properly the error later
   const auto p = StandardPacker::energy( newState.p );