#!/usr/bin/env python

import hddm_s
import ROOT

h2 = ROOT.TH2D("h2", "virtual spot, transverse vertex distribution",
               100, -1, 1, 100, -1, 1)
h2.GetXaxis().SetTitle("vertex x (cm)")
h2.GetYaxis().SetTitle("vertex y (cm)")
h1 = ROOT.TH1D("h1", "virtual spot, longitudinal vertex distribution",
               200, 0, 100)

nfiles = 0
for fin in open("samples"):
   for rec in hddm_s.istream(fin.rstrip()):
      origins = rec.getOrigins()
      if len(origins) > 1:
         h2.Fill(origins[1].vx, origins[1].vy)
         h1.Fill(origins[1].vz)
   nfiles += 1
   if nfiles == 10:
      break