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The attached backtest runs successfully.
But if I change the start and end dates from:
self.SetStartDate(2010, 1, 1)
self.SetEndDate(2010, 3, 31)to:
self.SetStartDate(2010, 1, 1)
self.SetEndDate(2010, 12, 31)Then the backtest will throw the following runtime error:
Runtime Error: IndexError : list index out of range IndexError : list index out of range
This is the stack trace:
System.Exception: IndexError : list index out of range ---> Python.Runtime.PythonException: IndexError : list index out of range
at Python.Runtime.PyObject.Invoke (Python.Runtime.PyTuple args, Python.Runtime.PyDict kw) [0x00033] in :0
at Python.Runtime.PyObject.InvokeMethod (System.String name, Python.Runtime.PyTuple args, Python.Runtime.PyDict kw) [0x00007] in :0
at Python.Runtime.PyObject.TryInvokeMember (System.Dynamic.InvokeMemberBinder binder, System.Object[] args, System.Object& result) [0x0003e] in :0
at (wrapper dynamic-method) System.Object.CallSite.Target(System.Runtime.CompilerServices.Closure, System.Runtime.CompilerServices.CallSite, object, QuantConnect.Data.UniverseSelection.SecurityChanges)
at QuantConnect.AlgorithmFactory.Python.Wrappers.AlgorithmPythonWrapper.OnFrameworkSecuritiesChanged (QuantConnect.Data.UniverseSelection.SecurityChanges changes) [0x0004f] in <60f7e514d9f742459223002854eb0074>:0
at QuantConnect.Lean.Engine.AlgorithmManager.Run (QuantConnect.Packets.AlgorithmNodePacket job, QuantConnect.Interfaces.IAlgorithm algorithm, QuantConnect.Lean.Engine.DataFeeds.ISynchronizer synchronizer, QuantConnect.Lean.Engine.TransactionHandlers.ITransactionHandler transactions, QuantConnect.Lean.Engine.Results.IResultHandler results, QuantConnect.Lean.Engine.RealTime.IRealTimeHandler realtime, QuantConnect.Lean.Engine.Server.ILeanManager leanManager, QuantConnect.Lean.Engine.Alpha.IAlphaHandler alphas, System.Threading.CancellationToken token) [0x008a6] in Lean.Engine.Alpha.IAlphaHandler alphas, System.Threading.CancellationToken token) [0x008a6] in <07c77997a4904cb4925edfc7c062ccfe>:0
--- End of inner exception stack trace ---
I couldn't figure out what went wrong because I don't know which file and line in my code that is throwing this exception.
Please help.
Shile Wen
Hi Moeh,
The error is caused by the warmup function in alphamodel line 75, because sometimes the history DataFrame is empty. As a fix, I suggest adding the line
if history.empty: returnat the beginning of the warmup function to make sure indexing errors don’t occur. I've also attached a backtest with the fix.For the future, a great way to solve these problems could be through our debugger, and a guide on how to use it can be found here.
Best,
Shile Wen
Moeh12
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