Re: Missing events after h2root

Rene Brun (Rene.Brun@cern.ch)
Tue, 15 Dec 1998 18:55:14 +0100

>
> >From news Tue Dec 15 16:30 MET 1998
> Path: cern.ch!claire.desy.de!not-for-mail
> From: Stefan Stonjek <stonjek@mail.desy.de>
> Newsgroups: cern.root
> Subject: Missing events after h2root
> Date: 15 Dec 1998 15:28:22 GMT
> Organization: Deutsches Elektronen-Synchrotron (DESY)
> Lines: 31
> Message-ID: <755v6m$hvc$1@claire.desy.de>
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>
> Hello,
>
> I have a problem when I convert my existing HBOOK NTuple to root.
> When I use h2root, the nuber of events is what I expect:
> ******************************************************************************
> *Tree :h200 : Result *
> *Entries : 1070694 : Total Size = 227934634 bytes File Size = 46696268 *
> * : : Tree compression factor = 4.90 *
> ******************************************************************************
>
> When I open the file with root or with a program linked against the root
> library I get a smaller number of events:
> ******************************************************************************
> *Tree :h200 : Result *
> *Entries : 939942 : Total Size = 200353854 bytes File Size = 41070358 *
> * : : Tree compression factor = 4.90 *
> ******************************************************************************
>
> This deffinitly saves disk space but this is deffinitly not what I want.
>
> This behavior is reproduceble also in different version (2.00/12 and 2.00/13).
> I would like to hear any hints to cure the problem. Thank You!
>
> Tschuess
> Stefan
>

Hi Stefan,
I am convinced that you have used h2root from version 2.00/12.
By default, Root autosaves the Tree header every 100 Mbytes.
In your case, you see the second cycle of the Autosave after 200 Mbytes.
Version 2.00/12 had a problem when more than one cycle of an object was
written to a file. This was fixed in 2.00/13. See release notes.
Please convert your file with h2root from version 2.00/13
and let me know.

Rene Brun