Some question

ROOT
1

hello,

When I open a file and list its contents, the output is like this:

[color=red]root [1] TFile f=new TFile(“N12cross.025.root”)
root [2] f.ls()
TFile* N12cross.025.root
TFile* N12cross.025.root
KEY: TTree T;3 lijiaxing
KEY: TTree T;2 lijiaxing
root [3][/color]

I have two questions:

  1. the means of “[color=red]TFile** N12cross.025.root[/color]” and “[color=red]TFile* N12cross.025.root[/color]”
  2. to make the start 2, not 1, what shall I do?

Thanks !
foolfish

2

Hi,

On represent the file, the other represent the top directory (which happens to be the file)

[quote] 2. to make the start 2, not 1, what shall I do? [/quote]When storing the object there is an option that will let you keep all the cycle (aka version) of your object in the file. By default we keep only the last 2.

Cheers,
Philippe.