Hi,
if you wish to run this code in a macro called Analyzer.C you should pass a parameter to it (the run number)
root -b -q 'Analyzer.C(123456)'
see root.cern.ch/root/htmldoc/guide … ot-session .
If not, at the prompt, the usual syntax will do the job:
root[0] .L Analyzer.C
root[1] Analyzer(123456)
Cheers,
D