UnboundLocalError: local variable 'sumOfSquares' referenced before assignment

[Rob Smith]

http://graphite/render/?target=stdev(*.natasha.memory.active,100)&format=json

Traceback (most recent call last):
  File "/usr/lib64/python2.6/site-packages/django/core/handlers/base.py", line 111, in get_response
    response = callback(request, *callback_args, **callback_kwargs)
  File "/opt/graphite/webapp/graphite/render/views.py", line 105, in renderView
    seriesList = evaluateTarget(requestContext, target)
  File "/opt/graphite/webapp/graphite/render/evaluator.py", line 10, in evaluateTarget
    result = evaluateTokens(requestContext, tokens)
  File "/opt/graphite/webapp/graphite/render/evaluator.py", line 21, in evaluateTokens
    return evaluateTokens(requestContext, tokens.expression)
  File "/opt/graphite/webapp/graphite/render/evaluator.py", line 29, in evaluateTokens
    return func(requestContext, *args)
  File "/opt/graphite/webapp/graphite/render/functions.py", line 1069, in stdev
    (sd, sumOfSquares) = doStdDev(sumOfSquares, toDrop, series[index+time], time, avg)
UnboundLocalError: local variable 'sumOfSquares' referenced before assignment

[Michael Leinartas (mleinartas)]

This is due to the series having missing points. The specific stacktrace here was fixed sometime after 0.9.9 but missing data now triggers this instead:

Traceback (most recent call last):
  File "/usr/lib/python2.6/site-packages/django/core/handlers/base.py", line 100, in get_response
    response = callback(request, *callback_args, **callback_kwargs)
  File "/usr/lib/python2.6/site-packages/graphite/render/views.py", line 105, in renderView
    seriesList = evaluateTarget(requestContext, target)
  File "/usr/lib/python2.6/site-packages/graphite/render/evaluator.py", line 10, in evaluateTarget
    result = evaluateTokens(requestContext, tokens)
  File "/usr/lib/python2.6/site-packages/graphite/render/evaluator.py", line 21, in evaluateTokens
    return evaluateTokens(requestContext, tokens.expression)
  File "/usr/lib/python2.6/site-packages/graphite/render/evaluator.py", line 29, in evaluateTokens
    return func(requestContext, *args)
  File "/usr/lib/python2.6/site-packages/graphite/render/functions.py", line 1310, in stdev
    (sd, sumOfSquares) = doStdDev(sumOfSquares, toDrop, series[index+time], time, avg)
  File "/usr/lib/python2.6/site-packages/graphite/render/functions.py", line 1268, in doStdDev
    return (math.sqrt((newSumOfSquares / float(n)) - (avg * avg)), newSumOfSquares)
ValueError: math domain error

[Michael Leinartas (mleinartas)]

I have a proposed fix to this, looking for comments: https://code.launchpad.net/~mleinartas/graphite/stdev/+merge/94248

[Michael Leinartas (mleinartas)]

Committed in r715