The ISLOGICAL function is one of the information functions. It is used to check for a logical value (TRUE or FALSE). If the cell contains a logical value, the function returns TRUE, otherwise the function returns FALSE.
Syntax
ISLOGICAL(value)
The ISLOGICAL function has the following argument:
Argument
Description
value
The value that you want to test. The value can be an empty cell, error, logical value, text, number, reference value, or a name referring to any of these.