[Rivet] Merging aida files

[Gavin Hesketh]

Hi Frank,
take the same histogram from (say) 3 aida files, weight each one, then 
add the histograms together (ie sum the contents of bin X over the three 
files) to get the new aida file.

I'm trying to run alpgen (sorry!), and have to generate eg Z+0lp, Z+1lp, 
Z+2lp separately, then add the results after the pythia step. The Xlp 
samples should be weighted to correspond to the same luminosity, but you 
don't know the cross section or number of events until after the pythia 
step. So, then only way I can think to do this is to merge the aida 
files with individual weights somehow.

But maybe there is a better way to run alpgen with rivet?

cheers,
	Gavin


On 08/12/10 18:55, Frank Siegert wrote:
> Hi Gavin,
>
> On 08/12/10 19:32, Gavin Hesketh wrote:
>> I was looking for a way to merge aida files from different runs into
>> one. The way I can up with is:
>>
>> aida2root XX.adia
>> merge the root files, adding histograms & normalising each as needed
>> root2flat XX.root
>> flat2aida XX.dat
>
> Do you mean merge as in "average" (combine statistics), or as in "add
> the bin contents"?
>
> Frank