Need help counting Occurrences

Hello ROOTers!

In this histogramm I need to count rates of coincidences. I am using a TTree called “tree” which has several branches called “Adc1”, “Adc2” and so on. The histogram is produced by

tree->draw("Adc1:Adc2","Adc3>>0","")

The usual methods of counting the contents of bins do not work here. Since I am still new to ROOT I really need help with this. Is there an easy way to do this?

Bye,
Twig

Hi,

Do you really mean '“Adc3>>0” which is (as far as I can tell) exactly the same as "“Adc3”?

[quote]The usual methods of counting the contents of bins[/quote]What do you mean?

If you need Draw to create a 2D histogram rather than a graph, you should use:tree->draw("Adc1:Adc2","Adc3>0","histo")

Cheers,
Philippe.