Logical Expressions

Logical expressions result in the value TRUE or FALSE. These are represented as integers where 0 is FALSE and anything else (usually 1) is TRUE. Logical expressions are normally used within IF THEN ELSE instructions and DO loops. They include:

  • Expressions combined with the comparison operators. For example:

    %%x = %%y > %%z

    (%%x will be 1 (TRUE) if %%y is greater than %%z.)

    %%x = %%y = %%z

    (%%x will be 1 (TRUE) if %%y equals %%z)

  • Expressions combined with the logical connectors. The AND and OR connectors combine two expressions, while the NOT connector negates the single expression following it. For example:

    %%x = %%y AND %%z

    (%%x will be 1 (TRUE) if both %%y and %%z are TRUE (not 0)).

  • A logical function. For example:

    %%x = CHANGED(%%y)

    (%%x will be either 1 (TRUE) or 0 (FALSE)).

Enrichment automatically converts string expressions to numeric expressions and vice versa. Therefore, you can use any field variable as a number or use numeric calculations as strings.