/sys$common/syshlp/helplib.hlb RTL Routines, MTH$, MTH$HATANH, Arguments  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 h-atanh

    OpenVMS usage:floating_point
    type:         H_floating
    access:       write only
    mechanism:    by reference

    Hyperbolic arc tangent of the hyperbolic tangent specified by
    hyperbolic-tangent. The h-atanh argument is the address of an H-
    floating number that is this hyperbolic arc tangent. MTH$HATANH
    writes the address of the hyperbolic arc tangent into h-atanh.

 hyperbolic-tangent

    OpenVMS usage:floating_point
    type:         H_floating
    access:       read only
    mechanism:    by reference

    Hyperbolic tangent of an angle. The hyperbolic-tangent argument
    is the address of a floating-point number that is this hyperbolic
    tangent. For MTH$HATANH, hyperbolic-tangent specifies an H-
    floating number.