RE: histograms embedded in TCanvas

He-he.
1. are you sure, you read canvas from file with this syntax?
2. how do you know, that TCanvas in a file contains something?
________________________________________
From: Adrian Sevcenco
Sent: 13 February 2012 21:25
To: Timur Pocheptsov; roottalk_at_root.cern.ch
Subject: Re: [ROOT] histograms embedded in TCanvas

On 02/13/12 21:47, Timur Pocheptsov wrote:
> Hi Adrian.
Hi Timur!!

> Read your canvas and ask it for a list of primitives?
>
> TCanvas * c = (TCanvas *)f->Get(.....);
> if (c) {
> ....
>   TList *primitives = c->GetListOfPrimitives();
well i have this code :

TFile *f = new TFile("spectra_kaon_minus.root"); if (!f) return;

f->ls();

TCanvas *c = new TCanvas ("f:cCanvas_kaon_minus");
TList *p = c->GetListOfPrimitives();
p->Print();

and this is the output

root [0]
Processing test.C...
TFile**         spectra_kaon_minus.root
 TFile*         spectra_kaon_minus.root
  KEY: TCanvas  cCanvas_kaon_minus;1
Collection name='TList', class='TList', size=0

is there other way to investigate contents of the canvas?

Большое спасибо :),
Adrian


>
>   ///iterate on this list.
>
> }
> ________________________________________
> From: owner-roottalk_at_root.cern.ch [owner-roottalk_at_root.cern.ch] on behalf of Adrian Sevcenco [Adrian.Sevcenco_at_cern.ch]
> Sent: 13 February 2012 20:24
> To: roottalk_at_root.cern.ch
> Subject: [ROOT] histograms embedded in TCanvas
>
> Hi! I have an root file that have an TCanvas saved inside.
> Inside in that TCanvas somehow there are a few histograms.
> How can i list and handle (access) those histograms?
>
> Thank you,
> Adrian