Quantopian's community platform is shutting down. Please read this post for more information and download your code.
Back to Community
Details on pre-startup "algo verification" phase, prior to debugger running, prior to fundamentals running
Simon Thornington
posted

Apologies if this is mentioned somewhere already, but I am getting these odd "runtime errors" which appear to be caused by some pre-execution checking phase, but they seem most often to be spurious errors, since they occur before any data has been acquired and so things that should never be empty are empty, and so forth.

Does such a phase exist? Can we disable it? It's very annoying to have to add runtime checks for conditions that cannot occur, except in some bizarre Python version of pre-runtime validation.

3 responses
Alisa Deychman

Simon, what are the details of the "odd runtime errors"? And can you share the code that's triggering the error messages? If you don't want to share it publicly, you can add me as a collaborator in the IDE ([email protected]). This will help give a more concrete answer!

Disclaimer

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 Quantopian. In addition, the material offers no opinion with respect to the suitability of any security or specific investment. No information contained herein should be regarded as a suggestion to engage in or refrain from any investment-related course of action as none of Quantopian nor any of its affiliates is undertaking to provide investment advice, act as an adviser to any plan or entity subject to the Employee Retirement Income Security Act of 1974, as amended, individual retirement account or individual retirement annuity, or give advice in a fiduciary capacity with respect to the materials presented herein. If you are an individual retirement or other investor, contact your financial advisor or other fiduciary unrelated to Quantopian about whether any given investment idea, strategy, product or service described herein may be appropriate for your circumstances. All investments involve risk, including loss of principal. Quantopian 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.

Simon Thornington

So far they are errors that are caused when something is empty or missing. However, they should be impossible, if all the functions are called in the usual order.

They happen prior to the debugger being started, so one cannot set a breakpoint at the error to see how it could be empty. Thus I assumed it was some pre-run validation phase that called handle_data with empty data, to catch errors before starting a backtest. Of course, that's not very helpful in python.

Anyway, tonight I'll try to make a replicable example.

Grant Kiehne

Alisa,

I've seen these build errors, too, and I agree that they can be challenging to debug. I recall Jonathan Kamens giving me a hand once; maybe he can provide a description of the process that you can post to the help page.

Here's another example:

https://www.quantopian.com/posts/build-error-help

Grant

About Quantopian
Careers
Community
Events
Documentation
Academia
Lectures
Status
Facebook
Twitter
LinkedIn
YouTube
Terms of Use
Privacy Policy

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 Quantopian.

In addition, the material offers no opinion with respect to the suitability of any security or specific investment. No information contained herein should be regarded as a suggestion to engage in or refrain from any investment-related course of action as none of Quantopian nor any of its affiliates is undertaking to provide investment advice, act as an adviser to any plan or entity subject to the Employee Retirement Income Security Act of 1974, as amended, individual retirement account or individual retirement annuity, or give advice in a fiduciary capacity with respect to the materials presented herein. If you are an individual retirement or other investor, contact your financial advisor or other fiduciary unrelated to Quantopian about whether any given investment idea, strategy, product or service described herein may be appropriate for your circumstances. All investments involve risk, including loss of principal. Quantopian 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.