CRPRSO ( centre, axis, radius, nsides, height, prism, ifail )
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  Create prismatic solid

Receives:
  KI_vec_position           centre         --- centre of prism
  KI_vec_axis               axis           --- axis of prism
  KI_dbl_radius            *radius         --- radius of enclosing cylinder
  int                      *nsides         --- number of sides
 <KI_dbl_distance>         *height         --- height of prism

Returns:
  KI_tag_body              *prism          --- prism
  KI_cod_error             *ifail          --- failure indicator

Specific errors:
  KI_lt_3_sides             Number of sides is less than 3

Description:
  If 'height' is positive, a body is created that is a right regular prism of
  'nsides' sides. One of the end faces (regular polygons of 'nsides' sides) is
  centred at 'centre', and the prism extends a distance 'height' in the
  direction of 'axis'. The prism is inscribed in a cylinder of radius 'radius'.

  If 'height' is zero, a sheet body is created whose face is a regular polygon
  of 'nsides' sides. The polygon is centred at 'centre', and the normal to the
  its plane face is parallel to 'axis'. Its circumscribing circle has radius
  'radius'.

  In either case, if 'axis' is parallel to the Z-axis (0,0,1) then one side
  (face or edge) will be perpendicular to the Y-axis, on the positive-Y side of
  'centre'. If 'axis' is not parallel to the Z-axis, the orientation of the body
  about 'axis' is undefined.