[Rivet] multipying two histos?

[Andy Buckley]

Hi Lars,

I guess you haven't had a chance to address this yet, but I thought you
should know that I just updated the source for your CDF 1994 and D0 2004
analyses while fixing some uses of the deprecated TotalVisibleMomentum
projection.

I noticed that in these analyses there is an identical (copy-and-pasted,
I guess) block of code in the init method which sets up a vetoed final
state to exclude low pT muons... this then isn't used anywhere. Can you
check whether this should be being used by the CalMET projection, or if
it can be safely removed entirely? I've marked these in the code with a
@todo as usual.

Cheers,
Andy


On 06/05/10 11:56, Andy Buckley wrote:
> On 01/05/10 13:31, Lars Sonnenschein wrote:
>> Hello Andy, (all),
>> I have now implemented and filled with sense the histos with the 
>> CDSsim/Idealsim correction factors into the CDF_1994_S2952106 analysis. 
>> But when I try to multiply it seems not to work, the output histos don't 
>> change. I use:
>>
>>  AIDA::IHistogramFactory& hf = histogramFactory();
>>  hf.multiply("/_histJet3eta", *_histJet3eta, *_histEta3Corr);
>>  
>> where the _histEta3Corr is the histo which contains the correction 
>> factors. I have written them out to check that they are filled reasonably.
>> What I want to do is:
>> _histJet3eta = _histJet3eta * _histEta3Corr;
>>
>> I have tried a couple of other things, unfortunatey without success.
>> If somebody has an idea how to get this working.
> 
> Hi Lars,
> 
> You should check the AIDA/LWH classes for info on how the
> HistogramFactory works. Of course it produces output in the AIDA path
> specified as the first argument string, so if you were expecting
> "/_histJet3eta" to somehow be translated into the variable _histJet3eta,
> that certainly won't work. Possibly you need to make a temporary
> histogram and then write the result of the multiplication into the
> correct output path. My guess is that your current AIDA output contains
> an extra histogram called "/_histJet3eta", with the correct values in it.
> 
> Cheers,
> Andy
> 


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