/***************************************************************************
* SVD.h                                                                    *
*                                                                          *
* Singular Value Decomposition.                                            *
*                                                                          *
*   HISTORY                                                                *
*      Name    Date          Description                                   *
*                                                                          *
*      arvo    08/22/2000    Split off from Matrix.h                       *
*      arvo    06/28/1993    Rewritten from "Numerical Recipes" C-code.    *
*                                                                          *
*--------------------------------------------------------------------------*
* Copyright (C) 2000, James Arvo                                           *
*                                                                          *
* This program is free software; you can redistribute it and/or modify it  *
* under the terms of the GNU General Public License as published by the    *
* Free Software Foundation.  See http://www.fsf.org/copyleft/gpl.html      *
*                                                                          *
* This program is distributed in the hope that it will be useful, but      *
* WITHOUT EXPRESS OR IMPLIED WARRANTY of merchantability or fitness for    *
* any particular purpose.  See the GNU General Public License for more     *
* details.                                                                 *
*                                                                          *
***************************************************************************/
#ifndef __SVD_INCLUDED__
#define __SVD_INCLUDED__

#include <util/Vector.h>
#include <util/Matrix.h>

class SVD {
    public:
        SVD( );
        SVD( const SVD    & );  // Copies the decomposition.
        SVD( const Matrix & );  // Performs the decomposition.
       ~SVD() {};
        const Matrix &Q( double epsilon = 0.0 ) const;
        const Matrix &D( double epsilon = 0.0 ) const;
        const Matrix &R( double epsilon = 0.0 ) const;
        const Matrix &PseudoInverse( double epsilon = 0.0 );
        int   Rank( double epsilon = 0.0 ) const;
        void  operator=( const Matrix & );  // Performs the decomposition.
    private:
        int Decompose( Matrix &Q, Matrix &D, Matrix &R );
        Matrix Q_;
        Matrix D_;
        Matrix R_;
        Matrix P_; // Pseudo inverse.
        int    error;
    };

#endif