#### 8.2.44 NaC ¶

Function: `out =` NaC `()` ¶
Function: `out =` NaC `(sz)` ¶

  “Not-a-Categorical". Creates missing-valued categorical arrays.

  Returns a new `categorical` array of all missing values of the given size. If no input sz is given, the result is a scalar missing categorical.

  `NaC` is the `categorical` equivalent of `NaN` or `NaT`. It represents a missing, invalid, or null value. `NaC` values never compare equal to any value, including other `NaC`s.

  `NaC` is a convenience function which is strictly a wrapper around `categorical.undefined` and returns the same results, but may be more convenient to type and/or more readable, especially in array expressions with several values.

  See also: categorical.undefined