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Dynamic values for symbol, symbols, and sid functions

Is there a good reason why the parameters for these functions can't be dynamic? Has anyone come up with a workaround for this?

1 response

Simply put, this was a design decision from the early stages of the platform. The securities are statically initialized, and the backtest can quickly fetch the needed data from our database, returning it to your window. If it's dynamic, this is done on the fly and is slower.

Quantopian now supports dynamic trading universes, so this design isn't as relevant, but it's deeply embedded within the architecture. There isn't a workaround available, but if you're looking for dynamic values, I would suggest to use set_universe or fundamentals to select your stocks. Those universes get updated automatically based on the criteria. And we are working to add other dynamic universe selections.

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