OpenVMS usage:complex_number
    type:         F_floating complex, D_floating complex, G_floating
                  complex, IEEE S_floating complex, IEEE T_floating
                  complex
    access:       write only
    mechanism:    by value

    Complex result of raising a complex base to an integer exponent.
    OTS$POWCJ returns an F-floating complex number. OTS$POWCDJ_R3
    returns a D-floating complex number. OTS$POWCGJ_R3 returns a G-
    floating complex number. OTS$POWCGS_R3 returns an IEEE S-floating
    complex number. OTS$POWCGT_R3 returns an IEEE T-floating complex
    number. In each format, the result and base are of the same data
    type.