COBOL Manual for TNS/E Programs (H06.08+, J06.03+)

When the SEPARATE phrase is present, the sign is maintained as a separate character to be
considered in the size of the item. A plus (+) for a positive value or a minus (-) for a negative
value is placed at the beginning or end of the item’s value, depending on the presence of
LEADING or TRAILING. If the sign character position contains a value other than plus (+) or
minus (-), any operation that uses the item as a numeric sending item has undefined results.
If the SEPARATE phrase is absent, negative values are represented by a modification of the
high-order bit of the high-order or low-order digit of the stored number (depending on the
presence of LEADING or TRAILING). The sign is not considered in the size of the item. For
positive values of the data item, the value of the sign bit is 0; for negative values, the value
of the sign bit is 1.
NOTE: If you move a data item with an included sign to another item with a group move,
the character with a negative sign is not a legitimate COBOL character. This can cause
problems. Use an item with an included sign only in operations that expect numeric data.
• Use of SIGN With Elementary or Data Structures
The SIGN clause can appear in the description of an elementary item or a data structure.
When it appears in the description of an elementary item, it specifies the sign attributes for
that item. The SIGN clause never applies to a data structure, whose category is always
alphanumeric. When it appears in the description of a data structure, it specifies the sign
attributes of every signed numeric item belonging to that group, except as noted.
• A Lower-Level SIGN Clause Overrides an Upper-Level One
A SIGN clause appearing in the data description entry of a data structure or a numeric data
item overrides the SIGN clause of any data structure to which that item is subordinate; therefore,
when more than one SIGN clause apparently applies to a data item, the one specified at the
lowest level in the hierarchy takes precedence over the ones specified at a higher level.
• Data Structure With SIGN Clause Must Include DISPLAY Numeric
When the data description entry of a data structure includes the SIGN clause, at least one
subordinate elementary item must be numeric and be described with a PICTURE character-string
containing S. All such items must be USAGE DISPLAY.
• Elementary Item With SIGN Clause Must Be DISPLAY Numeric
When the data description entry of an elementary item includes the SIGN clause, its category
must be numeric, it must be described with a PICTURE character-string containing S, and it
must be USAGE DISPLAY.
• The SIGN clause cannot be used for national data items.
OCCURS Clause for Fixed-Size Tables
The OCCURS clause defines tables (sets of repeated items), eliminating the need for separate item
entries. These tables can contain a fixed number of elements or can vary within given limits. The
OCCURS clause without a DEPENDING phrase defines a fixed-size table.
Descriptions of Records (Levels 01-49) 211