Hi All,

I'm relatively new to quantconnect and object oriented programming. I'm attempting to replace the MACD indicator use in the example MacdAlphaModel.py with a donchian channel. I've followed the structure as closely as possible but have received this error:

Runtime Error: TypeError : No constructor matches given arguments: (, , )  at __init__    self.donchian = DonchianChannel(upperBand in Alpha6.py:line 35 TypeError : No constructor matches given arguments: (, , )

Any help as to how to fix this would be great.

Thankyou!

Code:

class Donchian6(AlphaModel):
   
   def __init__(self, lowerBand = 55, upperBand = 55, resolution = Resolution.Daily):
       self.lowerBand = lowerBand
       self.upperBand = upperBand
       self.resolution = resolution
       
       self.insightPeriod = Time.Multiply(Extensions.ToTimeSpan(resolution), upperBand)
       self.symbolData = {}

       resolutionString = Extensions.GetEnumString(resolution, Resolution)
       self.Name = '{}({},{},{})'.format(self.__class__.__name__, lowerBand, upperBand, resolutionString)
       

   def Update(self, algorithm, data):
       
       insights = []
       
       return insights
       
   def OnSecuritiesChanged(self, algorithm, changes):
       for added in changes.AddedSecurities:
           self.symbolData[added.Symbol] = SymbolData(algorithm, added, self.lowerBand, self.upperBand, self.resolution)
       
       for removed in changes.RemovedSecurities:
           data = self.symbolData.pop(removed.Symbol, None)
           if data is not None:
               algorithm.SubscriptionManager.RemoveConsolidator(removed.Symbol, data.Consolidator)
               
class SymbolData:
   def __init__(self, algorithm, security, lowerBand, upperBand, resolution):
       self.Security = security
       self.donchian = DonchianChannel(upperBand, lowerBand, resolution)
       
       self.Consolidator = algorithm.ResolveConsolidator(security.Symbol, resolution)
       algorithm.RegisterIndicator(security.Symbol, self.donchian, self.Consolidator)

Author