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

 angle-in-degrees

    OpenVMS usage:floating_point
    type:         F_floating, D_floating, G_floating
    access:       read only
    mechanism:    by reference

    Angle (in degrees). The angle-in-degrees argument is the address
    of a floating-point number that is this angle. For MTH$SIND,
    angle-in-degrees specifies an F-floating number. For MTH$DSIND,
    angle-in-degrees specifies a D-floating number. For MTH$GSIND,
    angle-in-degrees specifies a G-floating number.