INTERFACE SPPolyFunction;

(* Polynomial functions on the sphere *)

IMPORT Wr, Rd, SPFunction;

TYPE
  LONG = LONGREAL;

TYPE
  T <: PublicT;

  PublicT = SPFunction.T OBJECT
      deg: CARDINAL;  (* Degree of polynomials *)
      c0: REF Coeffs; (* Coeffs of homog. polynomial of degree "deg" *)
      c1: REF Coeffs; (* Coeffs of homog. polynomial of degree "deg-1" *)
    METHODS
      write(wr: Wr.T); 
        (* 
          Writes the function to "wr". *)
          
      read(rd: Rd.T);  
        (*
          Reads the function from "rd", in the format
          created by "write". *)
    END;

TYPE
  Coeffs = ARRAY OF LONGREAL;
    (*
      A variable "c" of type "Coeffs" defines a homogeneous polynomial over "x",
      "y", and "z" with terms os total degree "d", for some "d" specified
      independently.  The order of the terms is defined in SPHomoLabel.i3. *)
  
END SPPolyFunction.