Secondary Vertex Example for BPhysics

[gordonwatts]

• Make sure we can get at the secondary vertex banks located in a typical physics file
• Make sure we can access the decorations (which are used quite heavily) in the file.

From Peter O:

Use this b-physics xAOD file: root://eosatlas.cern.ch//eos/atlas/user/d/daits/mc16_13TeV/DAOD_BPHY4/mc16.999031.P8BEG_23lo_ggX18p4_Upsilon1Smumu_4mu_3pt2.deriv.DAOD_BPHY4.e8304_a875_r10724_r10726_p3712_pUM999999/DAOD_BPHY4.999031._000001.pool.root.1

Some example PyROOT code:

PyROOT code example

for event in xrange(nEntries):
    t.GetEntry(event)

    for BPHY4Quads in t.BPHY4Quads:
        mass = BPHY4Quads.auxdataConst['float']('QUAD_mass')
        mindices = [int() for  in BPHY4Quads.auxdataConst['string']('CombinationCode')]
...
    closevalue = sorted(((_.chiSquared(), ) for  in t.BPHY4Quads if _.auxdataConst['string']('ChargeCode').count('+')==2),
                        )