## How does the ISLOGICAL function (DAX) work?

ISLOGICAL function (DAX) checks if a value (TRUE or FALSE) is a rational value and returns TRUE or FALSE. It is part of a group of functions called the IS functions, usually used to evaluate the outcome of error formulas.

## ISLOGICAL Formula Syntax

``ISINSCOPE (<columnName>)``

## How do you use the ISLOGICAL function?

ISLOGICAL function returns TRUE when a cell contains the logical values TRUE or FALSE, and returns FALSE for cells that contain any other value, including empty cells.

## Considerations when using the ISLOGICAL function

ISLOGICAL is part of a group of functions called the IS functions, which are often used to test the result of formulas for errors.

Use the ISLOGICAL function to check if a value is logical. ISLOGICAL will return TRUE when a value is TRUE or FALSE.

## Formula examples using the ISLOGICAL function

``````//RETURNS: Is Boolean type or Logical
=IF(ISLOGICAL(true), "Is Boolean type or Logical", "Is different type")

//RETURNS: Is Boolean type or Logical
=IF(ISLOGICAL(false), "Is Boolean type or Logical", "Is different type")

//RETURNS: Is different type
=IF(ISLOGICAL(25), "Is Boolean type or Logical", "Is different type")
``````

## Related Course Modules 