Re: GetMinimum() and GetMaximum() of events selected from a TTree and stored in a TEventList

Hi Matthias,

Thanks for this remark. I have now implemented support for event lists in TTree::GetMaximum and GetMinimum (SVN trunk).

Rene Brun

Matthias Kirsch wrote:
> Dear ROOT team,
>
> I have a question concerning TTree and TEventList (or TEntryList).
> After making a selection of events from a TTree and storing the result
> in a TEventList, I would like to get the minimum (or the maximum) of a
> variable ("iCount" in the example below).
> Neither TEventList nor TEntryList have a method GetMinimum(const char*
> columnname). If I set the pointer to the TEventList via SetEventList
> and use the GetMinimum(...) method of the TTree, the TEventList
> selection is not taken into account.
>
> TFile* tf = TFile::Open("testfile.root","READ")
> TTree* tt = (TTree*)tf->Get("testtree")
> testtree->GetMinimum("iCount")
> //returns 0
> testtree->Draw(">>elist","iCount > 10")
> TEventList* tel = (TEventList*)gDirectory->Get("elist")
> testtree->SetEventList(tel)
> testtree->GetMinimum("iCount")
> // returns 0 again
>
>
> Is there a way to get the minimum/maximum value of a branch without
> having to loop over the remaining entries in the TEventList, storing
> values in a map,...? (Asking the TLeaf "iCount" for its minimum
> returns the same value: 0.).
>
> I'm using ROOT v5.24 on a linux system.
>
> Cheers,
> Matthias
>
Received on Wed Aug 26 2009 - 13:15:45 CEST