code: def sphcyl(radius, colat, slon):
      
      radius = ctypes.c_double(radius)
      colat = ctypes.c_double(colat)
      slon = ctypes.c_double(slon)
      r = ctypes.c_double()
      lon = ctypes.c_double()
      z = ctypes.c_double()
      libspice.sphcyl_c(radius, colat, slon, ctypes.byref(r), ctypes.byref(lon),
                        ctypes.byref(z))
      return r.value, lon.value, z.value
docs: This routine converts from spherical coordinates to cylindrical
      coordinates.
  
      http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/sphcyl_c.html
  
      :param radius: Distance of point from origin.
      :type radius: float
      :param colat: Polar angle (co-latitude in radians) of point.
      :type colat: float
      :param slon: Azimuthal angle (longitude) of point (radians).
      :type slon: float
      :return:
              Distance of point from z axis,
              angle (radians) of point from XZ plane,
              Height of point above XY plane.
      :rtype: tuple