Re: TDSet

excuse me....
how to quit this mail group,roottalk ?
Thanks!

Cao Zhongxin(曹中鑫)
School of Physics, PKU, Beijing, China

On Mon, Sep 6, 2010 at 17:46, Marc Escalier <escalier_at_lal.in2p3.fr> wrote:

> thanks Gerardo
>
>
> What do you want to achieve?
>>
>
> i would like, for a given TDSet, know the number of entries
> and do a kind of truncature of the number of entries to a given number
>
> thank you
>
> ============================
>
> On Mon, 6 Sep 2010, Gerardo Ganis wrote:
>
>
>> Hi,
>>
>> On 09/05/2010 07:57 PM, Marc Escalier wrote:
>>
>>> Hello,
>>>
>>> would you know how to do, for a TDSet (which is different to a TChain) :
>>> -change the number of entries
>>> (for a TChain, it is TChain::SetEntries(...)
>>>
>> This does not make sense in TDSet, since you are not filling any tree.
>> What do you want to achieve?
>>
>> -read the number of entries
>>> (for a TChain, it is TChain::GetEntries(...)
>>>
>> This is not available. You have to loop over the elements.
>>
>> Note that TDSet maps the dataset as needed internally by PROOF and is
>> not
>> supposed to be a replacement of TChain.
>>
>> Gerri
>>
>>
>>
>>
>
Received on Mon Sep 06 2010 - 12:49:31 CEST