/cvmfs/atlas.cern.ch/repo/sw/ASG/AnalysisBase/2.4.31/CaloGeoHelpers/CaloGeoHelpers/proxim.h

#ifndef CALOGEOHELPER_PROXIM
#define CALOGEOHELPER_PROXIM

// inline function for handling two phi angles, to avoid 2PI wrap around. 
//

#include <math.h> 
#include "CxxUtils/AthUnlikelyMacros.h"

inline double proxim(double b,double a)
{
  const double aplus = a + M_PI;
  const double aminus = a - M_PI;
  if (ATH_UNLIKELY(b > aplus)) {
    do {
      b -= 2*M_PI;
    } while(b > aplus);
  }
  else if (ATH_UNLIKELY(b < aminus)) {
    do {
      b += 2*M_PI;
    } while(b < aminus);
  }
  return b;
}


#endif

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