A complex function designator specifies a function that returns a complex value: a value with a real part and an imaginary part.

<complex function designator>

──┬─<procedure identifier>─────────┬─┬─────────────────────────┬───────┤
  ├─<complex intrinsic name>───────┤ └─<actual parameter part>─┘
  └─<procedure reference variable>─┘

The procedure specified by the procedure identifier or the procedure reference variable must be of type COMPLEX.