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Newbie question about universe selection

when defining universe what is the difference between using "and" and "&" when using multiple constraints? Neither cause an error but result in a different selection.

thanks!

1 response

You must use the operators & , | or ~ to combine filters. The keywords and , or and not are not supported when combining pipeline filters. Unfortunately using the later (eg and) does not cause an error. The results however will not be as intended. This is why you are seeing the difference.

Stick to using just the single symbol operands. There's a little more on this in the documentation https://www.quantopian.com/docs/user-guide/tools/pipeline/#combining-filters.

Good catch and good luck.

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