[Rivet] Rivet 2 validation nearly done, and 2.0.0b3 tarball

[Andy Buckley]

Hi all,

Just so you know, I've sorted out all of the AIDA vs. YODA numerical
differences (other than those where AIDA was wrong) except for a few
analyses where divisions were failing because the numerator and
denominator have different binning (often one is a subset of the other,
but we don't have a magic behaviour in divide to handle this. It just
requires a bit of code restructuring and maybe some extra temporary
histograms... not a lot of work. Then we are done, I think... phew.

The JADE_OPAL jet rates analysis also has some differences w.r.t. the
AIDA version, because we changed the definition of which x-values are
used to define the integral upper limit. Hendrik and I looked at this at
Les Houches and what's implemented in the YODA branch is the best
choice, we think. The difference between using bin centers, foci, or
lower edges to define the integral limit is quite substantial, so a
second set of eyes on this analysis code would be very welcome. I
mention it particularly because I think this analysis was used for
shower tuning: David's H++ validation events look worse with the new
definition with the old. Perhaps/hopefully the new version is more
compatible with other data... worth cross-checking.

Also FYI, I added a bool parameter to the bookScatter2D(...) methods, so
that autobooking of points with x-values based on the ref data can be
enabled for those analyses where the x-values aren't derived from
properties of the event themselves -- typically a consequence of HEPDATA
not being aware that there can be data types without binning (or even
the concept of an x-axis).

Finally, I'm giving a talk/tutorial on Rivet at BOOST today. We're not
quite ready for a 2.0.0 release but it should be soon, and I want to be
able to point the audience at an up-to-date tarball: I'll make a 2.0.0b3
tag and tarball now.

Cheers,
Andy

-- 
Dr Andy Buckley, Royal Society University Research Fellow
Particle Physics Expt Group, University of Glasgow / PH Dept, CERN