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What troubleshooting steps should I take when it comes to figuring out why the results differ when I try running a local backtest or local optimize on an Algo vs doing lean cloud backtest <Algo name> or via the web console?
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Fred Painchaud
Hi Axist,
I'd say the prime reason for different results for a locally run algo vs the same algo run in the cloud is differing data. I would first make 100% sure that both runs use the exact exact same data. When that's the case and still I see differences I would look at the LEAN versions I am using, are they the same. Then I would make sure I use the exact same “software stack”, like the same Python version (assuming your algo is in Python), same .NET, etc, etc. If they are, then I would simply deep dive into debugging, targeting the code that generates the first difference and see what happens locally. I would then use the cloud debugger to try to see differences.
Fred
Axist
The material on this website is provided for informational purposes only and does not constitute an offer to sell, a solicitation to buy, or a recommendation or endorsement for any security or strategy, nor does it constitute an offer to provide investment advisory services by QuantConnect. In addition, the material offers no opinion with respect to the suitability of any security or specific investment. QuantConnect makes no guarantees as to the accuracy or completeness of the views expressed in the website. The views are subject to change, and may have become unreliable for various reasons, including changes in market conditions or economic circumstances. All investments involve risk, including loss of principal. You should consult with an investment professional before making any investment decisions.
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