anaUltraScurve RuntimeWarning in ROOT 6 (Python 2.7.5 & Numpy 1.14.0)

[BenjaminRS]

Brief summary of issue

When testing PR #70 the output of running the scurve analyser produced a couple warnings in ROOT 6 with Python 2.7.5 & Numpy 1.14.0 which were not present in ROOT 5 with Python 2.6.6 & Numpy 1.11.3:

/afs/cern.ch/user/b/benjamin/gemdaq/gem-plotting-tools/anaUltraScurve.py:287: RuntimeWarning: invalid value encountered in greater
  reason[effectivePedestals[vfat] > 50] |= MaskReason.HighEffPed
/afs/cern.ch/user/b/benjamin/gemdaq/gem-plotting-tools/anaUltraScurve.py:295: RuntimeWarning: invalid value encountered in greater
  np.count_nonzero(effectivePedestals[vfat] > 50))

Types of issue

• Bug report (report an issue with the code)
• Feature request (request for change which adds functionality)

Expected Behavior

That the warnings do not appear

Current Behavior

Warnings appear - however the final output looks to be ok.

Steps to Reproduce (for bugs)

1. Use ROOT 6, eg on gem904qc8daq
2. Run:
   anaUltraScurve.py -i /afs/cern.ch/user/b/benjamin/public/GEM/Data/SCurveTestFile.root --type=short -f
3. Watch the text output

Possible Solution (for bugs)

Context (for feature requests)

Your Environment

• Version used: ROOT 6 (Python 2.7.5 & Numpy 1.14.0) on gem904qc8daq
• Shell used: bash