The logical operators work on truth (Boolean) values and deliver well-formed boolean values. A non-zero value is considered true, and a zero value is considered false. All logical operators return well-formed truth values of either zero or one.

Operator | Syntax | Description
LNOT .LNOT. !! | LNOT expression .LNOT. expression !! expression | Logical negation. See LNOT and !! operators.
LAND .LAND. && | expression 1 LAND expression 2 expression 1 .LAND. expression 2 expression 1 && expression 2 | Logical conjunction. See LAND and && operators.
LOR .LOR. || | expression 1 LOR expression 2 expression 1 .LOR. expression 2 expression 1 || expression 2 | Logical disjunction. See LOR and || operators.