Overview of $Date functions

All $DATE functions--$DATE, $DATEJ, $DATEP--accept two input arguments.

Syntax

$DATE(year-format,fill-character)

Where

• The year-format argument controls the format of the year based on the following input values:

Year-format input	Return format	Example: Year 2013 displayed as...
0	YY	13
1	YYYY	2013
2	CYY	113 (The first digit represents the century since 1900)

CYY represents the century-year format. The first digit represents the century since 1900. The CYY format can be manipulated using the CUSTOM parameter. Please consult the Rocket Model 204 Parameter and Command Reference Manual for a discussion of the CUSTOM parameter.

• The fill-character argument indicates a 1-byte fill character to place between the date components, as in the following examples:.

Code example	Return format	Example: July 11, 2013
$DATE(2,' ')	'CYY MM DD'	113 07 11
$DATE(0,'Z')	'YYzMMzDD'	13z07z11
$DATEJ(1,'-')	'YYYY-DDD'	2013-192
$DATEJ(1,)	'YYYYDDD'	2013192

Usage

$DATECHG, $DATECHK, $DATECNV, and $DATEDIF recognize a format of CYY as representing the century-year format as returned from the $DATE function. Conversion to and from the CYY format is fully supported.

In addition, if CUSTOM=1 is added to the User 0 CCAIN stream or set later using the RESET command, the following occurs: If a CYY date format is specified for conversion and only a YY input is supplied, the conversion is successfully completed by using the CENTSPLT and BASECENT parameters. For further details see Rocket Model 204 Parameter and Command Reference Manual for details regarding the BASECENT, CENTSPLT, and CUSTOM parameters.

Examples

• IF CUSTOM=1, BASECENT=19, and CENTSPLT=95, then:

Print command	Results
PRINT $DATECNV('CYYDDD','YYYYMMDD','96001')	19960101
PRINT $DATECNV('CYYDDD','YYYYMMDD','196001')	20960101
PRINT $DATECNV('CYYDDD','YYYYMMDD','95001')	19950101
PRINT $DATECNV('CYYDDD','YYYYMMDD','095001')	19950101

• If CUSTOM=1 is omitted, BASECENT=19, and CENTSPLT=95, then:

Print command	Results
PRINT $DATECNV('CYYDDD','YYYYMMDD','96001')	******
PRINT $DATECNV('CYYDDD','YYYYMMDD','196001')	20960101
PRINT $DATECNV('CYYDDD','YYYYMMDD','95001')	******
PRINT $DATECNV('CYYDDD','YYYYMMDD','095001')	19950101

• If CUSTOM=2 is added to the User 0 CCAIN stream or set later using the RESET command, the following occurs: If a CYY-format is specified for output conversion and the C indicator is zero, then C is eliminated. This is true for all $DATE function calls. For example:

If CUSTOM=2 then: PRINT $DATEJ(2) prints 97.001.

But if CUSTOM =2 is omitted, then PRINT $DATEJ(2) prints 097.001.

Julian dates

The Julian date is a 4-byte, packed decimal formatted as follows:

0CYYDDDF

where:

• 0 is a reserved filler
• C represents the century since 1900. For example:

C=0 represents years 1900-1999

C=1 represents years 2000-2099

• YY is 2-byte year
• DDD is 3-byte day
• F is positive sign nibble for packed decimal

Routines available for user-written date $functions

CCALL entry points have been added: DATE, DATE3, and DATE4. All routines must be called with T1 pointing to a 26-byte answer area. Technical Support recommends that you allocate the answer area using the VARS=(name, len) pushdown list variable of the ENTER macro. (See the Rocket Model 204 System Manager's Guide chapter on customizing function and translation tables for more information on the ENTER macro.)

The current date and time are stored in the area with this format:

Code entry point	Format used for storing...
DATE	'YY.DDD MON DD HH.MM.SS'
DATE3	'CYY.DDD MON DD HH.MM.SS'
DATE4	'YYYY.DDD MON DD HH.MM.SS'

All registers are returned intact with the exception of the DATE call. The DATE call changes only the T4 register, returning the number representing the current month (1-12).