-- File:        Jacobi.cdl
-- Created:     Tue May 14 18:21:21 1991
-- Author:      Laurent PAINNOT
--              <lpa@topsn3>
---Copyright:    Matra Datavision 1991, 1992



class Jacobi from math
    	---Purpose:
      	-- This class implements the Jacobi method to find the eigenvalues and
      	-- the eigenvectors of a real symmetric square matrix.
      	-- A sort of eigenvalues is done.

uses Vector from math, 
     Matrix from math,
     OStream from Standard

raises NotDone from StdFail

is

      Create(A: Matrix)
      	---Purpose:
      	-- Given a Real n X n matrix A, this constructor computes all its
      	-- eigenvalues and eigenvectors using the Jacobi method.
      	-- The exception NotSquare is raised if the matrix is not square.
      	-- No verification that the matrix A is really symmetric is done.
      
      returns Jacobi;
      

    IsDone(me)
    	---Purpose: Returns true if the computations are successful, otherwise returns false.
        ---C++: inline
    returns Boolean
    is static;
    

    Values(me)
    	---Purpose: Returns the eigenvalues vector.
        -- Exception NotDone is raised if calculation is not done successfully.
    	---C++: inline
    	---C++: return const&
    returns Vector
    raises NotDone
    is static;
    
    
    Value(me; Num: Integer)
    	---Purpose: returns the eigenvalue number Num.
        -- Eigenvalues are in the range (1..n).
        -- Exception NotDone is raised if calculation is not done successfully.
        ---C++: inline
    returns Real
    raises NotDone
    is static;
    
    
    Vectors(me)
    	---Purpose: returns the eigenvectors matrix.
        -- Exception NotDone is raised if calculation is not done successfully.
    	---C++: inline
    	---C++: return const&
    returns Matrix
    raises NotDone
    is static;
    
    
    Vector(me; Num: Integer; V : out Vector)
    	---Purpose: Returns the eigenvector V of number Num.
        -- Eigenvectors are in the range (1..n).    
        -- Exception NotDone is raised if calculation is not done successfully.
    	---C++: inline
    raises NotDone
    is static;



    Dump(me; o: in out OStream)
    	---Purpose: Prints information on the current state of the object.
    	--          Is used to redefine the operator <<.

    is static;


fields

Done:         Boolean;
AA:           Matrix;
NbRotations:  Integer;
EigenValues:  Vector;
EigenVectors: Matrix;

end Jacobi;