The INTEGER-OF-DAY function converts a date in the Gregorian calendar from Julian date form (`YYYYDDD`) to integer date form. The type of this function is integer.

## Usage

__FUNCTION__ __INTEGER-OF-DAY__ (`argument-1`)

## Parameter

`argument-1` must be an integer of the form

`YYYYDDD`, whose value is obtained from the calculation (

`YYYY` * 1000) +

`DDD`.

`YYYY` represents the year in the Gregorian calendar. It must be an integer greater than 1600.
`DDD` represents the day of the year. It must be a positive integer less than 367 provided that it is valid for the year specified.

## Returned Value

The returned value is an integer that is the number of days the date represented by
`argument-1` succeeds December 31, 1600 in the Gregorian calendar.