kshaw
February 11, 2008, 10:50am
1
Hi there

I am wanting to find the value for x on my histogram for which y = largest value.

So to find the maximum value for y (the peak of the histogram) I have

const Double_t MaxY = myHisto->GetMaximum();

but how do I then determine what the corresponding value on the x-axis is?

Many thanks
kate

tpochep
February 11, 2008, 11:11am
2
[quote]Hi there

I am wanting to find the value for x on my histogram for which y = largest value.

So to find the maximum value for y (the peak of the histogram) I have

const Double_t MaxY = myHisto->GetMaximum();

but how do I then determine what the corresponding value on the x-axis is?

Many thanks
kate[/quote]

What about int maxBin = hist->GetMaximumBin()? And hist->GetXaxis()->GetBinCenter(maxBin) ?

Or hist->GetBinCenter(maxBin)?

kshaw
February 11, 2008, 11:52am
3
Great

maxBin = hist->GetMaximumBin()
gets the bin I want (which correspondes to maximum Y value), then I multiply it by the bin size and got the value for x.

Thanks very much!
Kate