Around three months ago, all my projects that used to be working fine suddenly start throwing the runtime error:

Cannot convert null to 'bool' because it is a non-nullable value type (Open Stacktrace)

This is really frustrating because nothing was done and yet it changed from working to broken just overnight. I am already reducing my code to the bare minimum but this is still happening. Does anyone have similar experience?

from numpy import sort from numpy import mean from numpy import std from numpy import array from numpy import argpartition from numpy import zeros from scipy.stats import skew from collections import deque class CustomSimpleMovingAverage: def __init__(self, name, period): self.Name = name self.Time = datetime.min self.Value = 0 self.IsReady = False self.queue = deque(maxlen=period) def __repr__(self): return "{0} -> IsReady: {1}. Time: {2}. Value: {3}".format(self.Name, self.IsReady, self.Time, self.Value) # Update method is mandatory def Update(self, input): self.queue.appendleft(input.Close) count = len(self.queue) self.Time = input.EndTime self.Value = sum(self.queue) / count self.IsReady = count == self.queue.maxlen class DebugTest(QCAlgorithm): LookBackLen = 150 tradeSize = 1.0 skewThreshold = 0.1 selectTopN = 3 def Initialize(self): self.SetStartDate(2010, 12, 12) # Set Start Date self.SetCash(13000) # Set Strategy Cash self.AddEquity("XLP", Resolution.Daily) # Indicator self.custom = CustomSimpleMovingAverage('custom', 60) self.RegisterIndicator("XLP", self.custom, Resolution.Daily) self.SetBrokerageModel(BrokerageName.InteractiveBrokersBrokerage, AccountType.Margin) def OnData(self, data): for i in range(self.selectTopN): self.SetHoldings("XLP", 1.0)

 

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