Hi Max,
You can test for a NaN with:
Double_t r = tt->FindLeaf("jetdata.ijet_phi")->GetValue(1431)
if (TMath::IsNaN(r)) {...
Rene Brun
On Wed, 9
Jul 2003 mbrustke@purdue.edu wrote:
> I've read about some similar problems in the digest, but most of them seemed to
> involve histogramming, while mine simply involves accessing the values of
> leaves of a tree. I setup a tree using the following syntax:
> afile = new TFile("mc.root")
> TTree *tt = afile.Get("t")
> Unfortunately, my MC files are around 60 megs each, so I can't attach one. I
> am working on creating a smaller file with a few good events and one or two bad
> ones, but I'm still a novice with root. The problem happens with different
> instances of different variables, but the first one on which I noticed it was
> event #1431 of a variable called jetdata.ijet_phi. When I call
> tt->Scan("jetdata.ijet_phi")
> all values display properly, but if I call
> tt->FindLeaf("jetdata.ijet_phi")->GetValue(1431)
> I get:
> Error: Symbol nan is not defined in current scope FILE: LINE:0
> (const Double_t)nan
> *** Interpreter error recovered ***
> I have experienced this under versions 3.03/07, 3.03/09, and 3.05/03., all
> under various versions of Linux. As I said, tt->Scan displays reasonable
> looking values for the offending variables, and I can histogram them without
> error, but accessing certain ones individually results in nan. Even if there
> is no way to fix this, is there some way I can detect nan entries and simply
> skip them when I am looping over the entire dataset?
>
> Thanks,
> Max Brustkern
>
This archive was generated by hypermail 2b29 : Thu Jan 01 2004 - 17:50:13 MET