import ROOT, glob, math, sys, os
from ROOT import std
from array import array

outf = "./testdev.root"
paramf = "/nfs/hicran/project/panda/SIM/bergerm/fopiroot/tpc/FOPI/par/tpc.run3888.par"
rBin = -1 # -1 for calculating all r bins. rBin>0 calculate rbin rBin
mom = 3.672

nbinsr = 5
nbinsz = 10

ROOT.gROOT.ProcessLine(".x rootlogon.C") 
fRun = ROOT.FairRunSim()
fRun.SetBeamMom(mom)

efield = ROOT.TpcEFieldCyl("/nfs/hicran/project/panda/SIM/bergerm/fopiroot/macro/tpc/FOPI/mberger/last_strip/tpcfield.txt")
bfield = ROOT.PndMultiField("FULL") #use FOPI fieldmap
#bfield = ROOT.PndConstField();
#bfield.SetField(0.,0.,6.);
#bfield.SetFieldRegion(-50,50,-50,50,-2000,2000);
bfield.Init()

#the actual calculation
drifter = ROOT.TpcInhFieldDrifter(efield, bfield,
                                  outf, paramf, nbinsr, nbinsz,
                                  rBin )
print "Starting the drifter...."
print "Writing Deviation Map output to",outf

drifter.run()