[Rivet] HepMC in human readable format

[Andy Buckley]

Hi Hannes,

I may have been incredulous about the *expectation* that Rivet would
contain such a function, but I do see the usefulness of one. It won't be
high priority, but I'll look into providing a one-liner way to do it in
a future release. ATLAS has some fairly nice pretty-printing code that I
can probably "borrow" :-)

I did think that this would be as simple as

inline void printEvent(const GenEvent& evt) {
    HepMC::IO_AsciiParticles ascii_io(std::cout);
    ascii_io.write_event(&evt);
}

but unfortunately IO_AsciiParticles does not work the same way re.
stream constructors as does IO_GenEvent. If only HepMC were better...
but we're stuck with it now!

Cheers,
Andy


On 09/08/12 08:50, Hannes Jung wrote:
> Hi Andy
> 
> to print to HepMC in a readable format is very essential
> for people trying to learn what the MC is doing and to understand
> how to do a selection for the analysis, also using Rivet just for
> MC studies.
> 
> We have now several summerstudents, who use Rivet as an interface
> to the MCs and to perform different studies. For this an understanding of
> the event record is important.
> 
> Anyway, as I send yesterday in my mail, we have now managed to print
> the HepMC record in a readable format in Rivet, so this is fine now.
> Maybe it could be of help also for others to have this option available.
> 
> Cheers
> 
> Hannes
> 
> 
> 
> 
> On 09.08.2012, at 09:26, Andy Buckley wrote:
> 
>> Hi Hannes,
>>
>> Why on earth would Rivet have a "print event like PYTHIA" function? The
>> access to the GenEvent object with all the structure is one function
>> call away from Rivet::Event -- is that really "complicated and
>> difficult"?!
>>
>> We've tried to provide nicer ways than HepMC itself to access event
>> details -- iterating over particles, for example, is far easier than in
>> native HepMC. But our emphasis is on the histogrammed output more than
>> what's printed out to the terminal... and far more on the final state
>> and hadron relationships than the internal HepMC structure.
>>
>> Other than the HepMC print and IO_AsciiParticles functions (and reading
>> the ASCII format), there are also a few graphical visualisation tools,
>> e.g. mcviz, that might be of interest.
>>
>> Cheers,
>> Andy
>>
>>
>> On 07/08/12 21:27, Hannes Jung wrote:
>>> Dear Andy et al
>>>
>>> thanks a lot for your reply.
>>>
>>> It's really fascinating, how complicated and difficult very trivial
>>> things are in Rivet.
>>> It must be a MUST, that one can print out the HEPMC record in a
>>> readable format...
>>> but it seems I can only get it via
>>> event.genEvent().print()
>>> but then the format is cryptic.
>>>
>>> How do you people check, if selections etc are correct, if there is
>>> no way to printout
>>> what comes from the MC ?
>>>
>>> It would be really very good if this could be provided.... I tried to
>>> do it, but failed
>>> due to my ignorance in the Rivet structure... so if anyone can help
>>> there, I would
>>> be really, really very happy....
>>>
>>> I try to promote Rivet for our summer-students.... so.........
>>>
>>> Thanks a lot
>>>
>>> cheers
>>> Hannes
>>>
>>> On 07.08.2012, at 17:07, Andy Buckley wrote:
>>>
>>>> It's really a HepMC thing: Rivet doesn't include any special printout
>>>> formatting for GenEvents. The best I can think of offhand is, if you
>>>> have a Particle p, to use p.genParticle().print(). Any other HepMC
>>>> library function can also be used on the p.genEvent() reference.
>>>>
>>>> Hope that helps,
>>>> Andy
>>>>
>>>>
>>>> On 07/08/12 15:18, Hannes Jung wrote:
>>>>> Dear Rivet developers
>>>>>
>>>>> I was wondering, whether there is an easy way to print out the HepMC
>>>>> record in human readable format within Rivet, so that one can see
>>>>> directly the event one is analyzing ?
>>>>>
>>>>> Probably I have just not found the proper place, where this is
>>>>> described... any hint would be great...
>>>>>
>>>>> thanks a lot
>>>>>
>>>>> cheers
>>>>> Hannes
>>>>>
>>>>>
>>>>> ***********************************************************************
>>>>> Hannes Jung
>>>>> Email: Hannes.Jung at desy.de <mailto:Hannes.Jung at desy.de>
>>>>> <mailto:Hannes.Jung at desy.de>
>>>>> mobile :+49 40 8998 93741
>>>>> http://www.desy.de/~jung                                           
>>>>> Tel: +49 (0) 40 8998 3741         
>>>>> Fax: +49 (0) 40 8998 3093
>>>>> DESY, CMS 01B/02.213
>>>>> Notkestr.85, 22603 Hamburg, FRG   
>>>>> ***********************************************************************
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> _______________________________________________
>>>>> Rivet mailing list
>>>>> Rivet at projects.hepforge.org <mailto:Rivet at projects.hepforge.org>
>>>>> http://www.hepforge.org/lists/listinfo/rivet
>>>>>
>>>>
>>>>
>>>> -- 
>>>> Dr Andy Buckley, SUPA Advanced Research Fellow
>>>> Particle Physics Expt Group, University of Edinburgh
>>>>
>>>> The University of Edinburgh is a charitable body, registered in
>>>> Scotland, with registration number SC005336.
>>>>
>>>
>>> ***********************************************************************
>>> Hannes Jung
>>> Email: Hannes.Jung at desy.de <mailto:Hannes.Jung at desy.de>
>>> mobile :+49 40 8998 93741
>>> http://www.desy.de/~jung                                           
>>> Tel: +49 (0) 40 8998 3741         
>>> Fax: +49 (0) 40 8998 3093
>>> DESY, CMS 01B/02.213
>>> Notkestr.85, 22603 Hamburg, FRG   
>>> ***********************************************************************
>>>
>>>
>>>
>>>
>>>
>>
>>
>> -- 
>> Dr Andy Buckley, SUPA Advanced Research Fellow
>> Particle Physics Expt Group, University of Edinburgh
>>
>> The University of Edinburgh is a charitable body, registered in
>> Scotland, with registration number SC005336.
>>
> 
> ***********************************************************************
> Hannes Jung 
> Email: Hannes.Jung at desy.de <mailto:Hannes.Jung at desy.de> 
> mobile :+49 40 8998 93741
> http://www.desy.de/~jung                                           
> Tel: +49 (0) 40 8998 3741         
> Fax: +49 (0) 40 8998 3093 
> DESY, CMS 01B/02.213
> Notkestr.85, 22603 Hamburg, FRG   
> ***********************************************************************
> 
> 
> 
> 


-- 
Dr Andy Buckley, SUPA Advanced Research Fellow
Particle Physics Expt Group, University of Edinburgh

The University of Edinburgh is a charitable body, registered in
Scotland, with registration number SC005336.