COMPUTATIONAL-3 phrase or PACKED-DECIMAL phrase

Syntax rules

1. The COMPUTATIONAL-3 and PACKED-DECIMAL phrases are identical in meaning.

2. The phrases indicate that the data item is stored in internal decimal format (i.e. in packed form).

3. The PICTURE clause of a COMPUTATIONAL-3 or PACKED-DECIMAL item may contain no characters other than 9s, the operation sign S, the assumed decimal point V, and one or more Ps (see section "PICTURE clause").

General rule

1. Internal decimal data items are represented by 2 digits per byte; the sign is contained in the four low-order bits of the low-value byte.

   For internal decimal data items whose PICTURE clause contains no S, the represen-tation of the absolute value corresponds to the number.

For examples of the COMPUTATIONAL-3 or PACKED-DECIMAL table 17.

Format	PICTURE clause	USAGE and SIGN phrase	Value in external representation	Value in internal representation 4)	Bytes required	Conversion for arithmetic operation Alignment	Alignment if SYNC is specified
External decimal (zoned)	9999	DISPLAY	1234	F1F2F3F4	1 byte/digit	Yes, in order to conform to format of other operands or COMP-3 or PACKED-DECIMAL
	S9999		+1234	F1F2F3C41)2)
	S9999		-1234	F1F2F3D41)2)
	S9999	DISPLAY SIGN TRAILING	1234+	F1F2F3C4
			1234-	F1F2F3D4
	S9999	DISPLAY SIGN TRAILING SEPARATE	1234+	F1F2F3F44E	+ 1 byte for sign
			1234-	F1F2F3F460
	S9999	DISPLAY SIGN LEADING	+1234	C1F2F3F4
			-1234	D1F2F3F4
	S9999	DISPLAY SIGN LEADING SEPARATE	+1234	4EF1F2F3F4	+ 1 byte for sign
			-1234	60F1F2F3F4
Internal decimal (packed)	9999	COMP-3 or PACKED-DECIMAL	+1234	01234F2)	2 digits per byte, except for low-order byte which contains a digit and the sign	No, except when other operand is binary and conversion to binary would be more advantageous.	None
	9999		-1234	01234F2)
	S9999		+1234	01234C2)
	S9999		-1234	01234D2)
Binary	S9999	BINARY or COMP or COMP-5	+1234	04D2	2 bytes for 1-4 digits	No, except when used in mixed-form computations to maintain common formats, or if COMP-3 or PACKED-DECIMAL would be more advantageous.	Halfword
					4 bytes for 5-9 digits		Word
					8 bytes for 10-18digits		Word
					16 bytes for 19-31digits		Word
	S9999		-1234	FB2E	2		Halfword3)
Ext. floating point	+99.99E-99	DISPLAY	+12.34E+2	4EF1F26BF3F4C540 F0F2	1 byte per character	Yes. To internal floating-point	None
Int. floating point	None allowed	COMP-1	+12.34E+2	434D2000	4	No	Word
	None allowed	COMP-2	-12.34E-2	C01F972474538EF3	8	No	Doubleword

Table 17: Internal representation of internal data items

¹⁾ One byte per digit, except for the low-order byte which contains the sign in the first halfbyte and the last digit in the second halfbyte.

²⁾ Mode of sign representation:

F = non-printable plus sign (treated as an absolute value)
C = internal equivalent of plus sign
D = internal equivalent of minus sign.

³⁾ See rules for binary data items.

⁴⁾ Each character (letter/digit) represents a half byte.