safeLogRatio.h File Reference

#include <cmath>
#include "xAODJet/Jet.h"
#include "xAODBTagging/BTagging.h"

Include dependency graph for safeLogRatio.h:

This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Functions
float	safeLogRatio (float num, float denom)
const xAOD::Jet *	getJetFromBTagLink (const SG::AuxElement &btag)

Function Documentation

getJetFromBTagLink()

const xAOD::Jet * getJetFromBTagLink

(

const SG::AuxElement &

btag

)

safeLogRatio()

float safeLogRatio	(	float	num,
		float	denom )

Definition at line 10 of file safeLogRatio.cxx.

                                           {
  // ep(silon) is the smallest non-subnormal number
  // the recyprocal of this should not overflow
  float ep = std::numeric_limits<float>::min();
  float ratio = (std::abs(denom) < ep ? INFINITY : num / denom);
  return std::abs(ratio) < ep ? -INFINITY : std::log( ratio );
}