ZeroDivisionError: float division by zero

[Sebastian Vetter]

Re: anaylzer-vwr may have something error

Traceback (most recent call last):
  File "/home/svetter/.local/lib/python3.6/site-packages/django_extensions/management/commands/runjob.py", line 35, in runjob
    job().execute()
  File "/home/svetter/zenvest/analysis/jobs/daily/backtest_technical_analysis.py", line 325, in execute
    result = cerebro.run()
  File "/home/svetter/.local/lib/python3.6/site-packages/backtrader/cerebro.py", line 1127, in run
    runstrat = self.runstrategies(iterstrat)
  File "/home/svetter/.local/lib/python3.6/site-packages/backtrader/cerebro.py", line 1301, in runstrategies
    strat._stop()
  File "/home/svetter/.local/lib/python3.6/site-packages/backtrader/strategy.py", line 486, in _stop
    analyzer._stop()
  File "/home/svetter/.local/lib/python3.6/site-packages/backtrader/analyzer.py", line 200, in _stop
    self.stop()
  File "/home/svetter/.local/lib/python3.6/site-packages/backtrader/analyzers/vwr.py", line 154, in stop
    dt = pn / (pi * math.exp(ravg * n)) - 1.0
ZeroDivisionError: float division by zero

I just had my script run through a few iterations and actually ran into the same issue. I'm not quite sure how

(pi * math.exp(ravg*n) - 1.0

can be zero? with the exponential value of pi * (ravg*n) being exactly 1.0?

Did anyone else run into this? @backtrader what do you think about the suggestion made by the original author to add another check and potentially fill in NaN?

# add a more assert 
if pi * math.exp(ravg * n)!=0:
    dt = pn / (pi * math.exp(ravg * n)) - 1.0
else:
    dt = np.NaN