Weslley S. Pereira, University of Colorado Denver, U.S.

!>
!> Tests:
!>
!> (a) Inf inputs:
!>    (1) y = ( Inf + 0   * I)
!>    (2) y = (-Inf + 0   * I)
!>    (3) y = ( 0   + Inf * I)
!>    (4) y = ( 0   - Inf * I)
!>    (5) y = ( Inf + Inf * I)
!> Tests:
!>    (a) 0 * y is NaN.
!>    (b) 1 * y is y is either y or NaN.
!>    (c) y * y is either  Inf or NaN (cases 1 and 3),
!>                 either -Inf or NaN (cases 2 and 4),
!>                 NaN (case 5).
!>
!> (b) NaN inputs:
!>    (1) y = (NaN + 0   * I)
!>    (2) y = (0   + NaN * I)
!>    (3) y = (NaN + NaN * I)
!> Tests:
!>    (a) 0 * y is NaN.
!>    (b) 1 * y is NaN.
!>    (c) y * y is NaN.
!>
!>