isCOBOL Evolve : Language Reference : Data Division : Concept of Classes of Data
Concept of Classes of Data
There are five categories of data items, described by the PICTURE clause. These are grouped into three classes: alphabetic, numeric, and alphanumeric. For alphabetic and numeric, the classes and categories are synonymous. The alphanumeric class includes the categories of alphanumeric edited, numeric edited, and alphanumeric (without editing). Every elementary item belongs to one of the classes and further to one of the categories. The class of a group item is treated as alphanumeric regardless of the class of elementary items subordinate to that group item. The following table depicts the relationship of the class and categories of data items.
Level of item
Class
Category
Alphabetic
Alphabetic
Numeric
Numeric
Alphanumeric
Numeric edited
Alphanumeric edited
Alphanumeric
Alphanumeric
Alphabetic
Numeric
Numeric edited
Alphanumeric edited
Alphanumeric