The operator with the highest precedence in an expression is
    evaluated first. Following this, the next highest operator is
    evaluated, and so on. Operators with the same precedence are
    evaluated from left to right, as they appear in the expression.

       Operator  Precedence Description

       *         6          Arithmetic multiplication
       /         6          Arithmetic division
       +         5          Arithmetic plus
       -         5          Arithmetic minus
       .EQ.      4          Arithmetic equal
       .GE.      4          Arithmetic greater than or equal
       .GT.      4          Arithmetic greater than
       .LE.      4          Arithmetic less than or equal
       .LT.      4          Arithmetic less than
       .NE.      4          Arithmetic not equal
       .NOT.     3          Logical NOT
       .AND.     2          Logical AND
       .OR.      1          Logical OR