[Rivet] Validation & tuning phone meeting, Monday 29th Sept, 4pm (UK)

[Lars Sonnenschein]

On Fri, 10 Oct 2008, Andy Buckley wrote:

> Lars Sonnenschein wrote:
> > If you mean that I have to implement into RivetAIDA.hh a function 
> > integral(), where also the normalization() function has been implemented
> > then yes I can extract it.
> 
> Yes, or just call the AIDA objects directly. This sort of interface
> stuff will have to change when we replace AIDA.
> 
> > Somehow the bins of the Rivet divided histo have to be 
> > multiplied by the bin widths (x2GeV for the first bins and larger values 
> > for the later bins.) to get it close to flat, but I'm just guessing.
> 
> The bin width factors should be canceled out in the division, but it's
> possible that LWH's implementation of the histogram division gets this
> wrong and includes the width factor when creating the DataPointSet.
> That's worth checking (and fixing if it's the case).

I checked already the division code. It looks fine.

Now, how could the histogram which has been produced by the division of 
two other histograms possibly know that it should be treated differently 
from the other histograms when converted to DataPointSet?

I looked into the DataPointSetFactory. Indeed, it is divided by the bin 
width.
 
The histo would need e.g. a variable which could be set by the 
division function and the when converting to datapoint sets it could be 
checked if this variable is set, but it would need to be a publically 
accessible variable like the histo axis() and bin information variables.

Any concrete suggestions?

	Lars