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  • Committer: Chris Davis
  • Date: 2011-04-02 19:59:53 UTC
  • Revision ID: chrismd@gmail.com-20110402195953-9wq4n3hvqjni8ujf
attempt to fix Bug #697010

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Lines of Context:
webapp/graphite/render/functions.py
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   return (math.sqrt((newSumOfSquares / float(n)) - (avg * avg)), newSumOfSquares)
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def stdev(requestContext, seriesList,time):
 
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def stdev(requestContext, seriesList, time):
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  count = 0
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  for series in seriesList:
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    stddevs = TimeSeries("stddev(%s,%.1f)" % (series.name, float(time)), series.start, series.end, series.step, [])
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    stddevs.pathExpression = "stddev(%s,%.1f)" % (series.name, float(time))
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    avg = safeDiv(safeSum(series[:time]), time)
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    sumOfSquares = sum(map(lambda(x): x * x, [v for v in series[:time] if v is not None]))
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    (sd, sumOfSquares) = doStdDev(sumOfSquares, 0, 0, time, avg)
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    stddevs.append(sd)
 
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    if avg is not None:
 
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      sumOfSquares = sum(map(lambda(x): x * x, [v for v in series[:time] if v is not None]))
 
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      (sd, sumOfSquares) = doStdDev(sumOfSquares, 0, 0, time, avg)
 
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      stddevs.append(sd)
 
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    else:
 
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      stddevs.append(None)
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    for (index, el) in enumerate(series[time:]):
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      if el is None:
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      s = safeSum([safeMul(time, avg), el, -toDrop])
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      avg = safeDiv(s, time)
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      (sd, sumOfSquares) = doStdDev(sumOfSquares, toDrop, series[index+time], time, avg)
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      stddevs.append(sd)
 
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      if avg is not None:
 
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        (sd, sumOfSquares) = doStdDev(sumOfSquares, toDrop, series[index+time], time, avg)
 
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        stddevs.append(sd)
 
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      else:
 
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        stddevs.append(None)
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    for i in range(0, time-1):
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      stddevs.insert(0, None)