Hello,
[adding JB in cc]

we are using a copy of the code used for the HZZ analysis and the 
corresponding training.
Can you expand a bit on your worries about the round-off error ?

Thanks
Florian

On 17/12/13 10:49 AM, Lindsey Gray wrote:
> In RecoEgamma/EgammaElectronAlgos/src/RegressionHelper.cc:
>
>> +    elClass = -1;
>> +
>> +
>> +  bool isEcalDriven = ele.ecalDriven();
>> +  bool isTrackerDriven =  ele.trackerDrivenSeed();
>> +  bool isEB = ele.isEB();
>> +
>> +  // compute relative errors and ratio of errors
>> +  float energyRelError = energyError / energy;
>> +  float momentumRelError = momentumError / momentum;
>> +  float errorRatio = energyRelError / momentumRelError;
>> +
>> +  // calculate E/p and corresponding error
>> +  float eOverP = energy / momentum;
>> +  float eOverPerror = sqrt(
>> +			   (energyError/momentum)*(energyError/momentum) +
>
> Since we are being picky... @beaudett <https://github.com/beaudett> is
> this the same formula used in the training?
> I hope the MVA doesn't pick up on round-off error, otherwise I will
> apply a patch.
>
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