ISLOGICAL, ISNONTEXT, ISNUMBER, ISTEXT – DAX Guide

ISLOGICAL: Checks whether a value is a logical value (TRUE or FALSE).
https://dax.guide/islogical/

ISNONTEXT: Checks whether a value is not text.
https://dax.guide/isnontext/

ISNUMBER: Checks whether a value is a number.
https://dax.guide/isnumber/

ISTEXT: Checks whether a value is text.
https://dax.guide/istext/

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