Histogram sum

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#1

Hi guys,

I have an histo h giving the energy distribution in a given material. On the x axis I have the energy value and on the Y axis the corresponding number of occurrence. If I want to get the total energy, how should I do? Should I take the integral, namely h->Integral()?

Thanks

#2

I used
h->IntegralAndError(first_bin,last_bin,error,“width”));

with:
int first_bin = hist->FindFirstBinAbove(E_threshold,1); //1 for x axis
int last_bin = hist->FindLastBinAbove(E_threshold,1);

Is it correct?

#3

Try (sensitive to user’s changes to the current x-axis range):
std::cout << h->GetMean() * h->Integral() << "\n";
and/or (valid only for the “entire” x-axis range):
std::cout << h->GetMean() * h->GetSumOfWeights() << "\n";

#4

Hi @Wile_E_Coyote,

Why should I do GetMean()? And what do you mean by *?

#5

Do you think what I did is wrong?

#6

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