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Rule Expression Operators and Descriptions

A numeric or string operator is one of the symbols listed in the following table:

The Boolean operators .AND. and .OR. evaluate to either a decimal 1.0 for true or a 0 for false. The operands are treated as true if their values equal decimal 1.0, and anything else as false. Valid components of rule expressions are defined as follows:

• A decimal value is a rational number.
• A literal symbol is a symbol previously defined by the literal construct.
• A tally data cell is a data cell (see the Data Cell Types and Use section).
• Parentheses can be used to denote precedence.
• A numeric data cell is a data cell (see the Data Cell Types and Use section).
• An index specifier data cell is a data cell (see the Data Cell Types and Use section).
• A Boolean data cell is a data cell (see the Data Cell Types and Use section).
• A scan routine data cell is a data cell (see the Data Cell Types and Use section).
• A string item is either a string data cell (see the Data Cell Types and Use section) or a string literal, where the literal string is enclosed in quotation marks.
• A string operator is either the .EQS. or .NES. operator.
• A numeric binary operator is one of the operators in the previous table.