cgal/Algebraic_kernel_d/include/CGAL/RS/compare_1.h

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// Copyright (c) 2006-2008 Inria Lorraine (France). All rights reserved.
//
// This file is part of CGAL (www.cgal.org); you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public License as
// published by the Free Software Foundation; either version 3 of the License,
// or (at your option) any later version.
//
// Licensees holding a valid commercial license may use this file in
// accordance with the commercial license agreement provided with the software.
//
// This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
// WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
//
// $URL$
// $Id$
//
// Author: Luis Peñaranda <luis.penaranda@gmx.com>
#ifndef CGAL_RS_COMPARE_1_H
#define CGAL_RS_COMPARE_1_H
#include <mpfr.h>
#include <CGAL/RS/polynomial_1.h>
#include <CGAL/RS/algebraic_1.h>
#include <CGAL/RS/polynomial_1_utils.h>
#include <CGAL/RS/sign_1.h>
#include <CGAL/RS/refine_1_rs.h>
// default refinement and sign functions
#define CGALRS_REFINE_N(A,N) RS3::refine_1(A,N)
#define CGALRS_REFSTEPS 4
#define CGALRS_SIGNAT(P,M) RSSign::signat(P,M)
namespace CGAL{
namespace RS_COMPARE{
// compare two algebraic numbers, knowing they are not equal
//template <class _Gcd_policy>
Comparison_result
compare_1_unequal(const Algebraic_1 &r1,const Algebraic_1 &r2){
/*typedef _Gcd_policy Gcd;
mp_prec_t prec1=r1.get_prec();
mp_prec_t prec2=r2.get_prec();*/
CGALRS_REFINE_N(r1,CGALRS_REFSTEPS);
CGALRS_REFINE_N(r2,CGALRS_REFSTEPS);
while(r1.overlaps(r2)){
/*if(prec1<prec2 || r2.lefteval()==ZERO){
CGALRS_REFINE_N(r1,CGALRS_REFSTEPS);
prec1=r1.get_prec();
}else{
CGALRS_REFINE_N(r2,CGALRS_REFSTEPS);
prec2=r2.get_prec();
}
*/
CGALRS_REFINE_N(r1,CGALRS_REFSTEPS);
CGALRS_REFINE_N(r2,CGALRS_REFSTEPS);
}
return(mpfr_less_p(r1.right(),r2.left())?SMALLER:LARGER);
}
template <class _Gcd_policy>
Comparison_result
compare_1(const Algebraic_1 &r1,const Algebraic_1 &r2){
typedef _Gcd_policy Gcd;
/*if(r1.pol()==r2.pol())
return(r1.nr()!=r2.nr()?(r1.nr()<r2.nr()?SMALLER:LARGER):EQUAL);
*/
if(mpfr_lessequal_p(r1.left(),r2.left())){
if(mpfr_less_p(r1.right(),r2.left()))
return SMALLER;
}else{
if(mpfr_less_p(r2.right(),r1.left()))
return LARGER;
}
RS_polynomial_1 gcd=Gcd()(r1.pol(),r2.pol());
if(!gcd.get_degree())
return RS_COMPARE::compare_1_unequal/*<Gcd>*/(r1,r2);
Sign sleft,sright;
if(mpfr_greater_p(r1.left(),r2.left()))
sleft=CGALRS_SIGNAT(gcd,r1.left());
else
sleft=CGALRS_SIGNAT(gcd,r2.left());
if(sleft==ZERO)
return EQUAL;
if(mpfr_less_p(r1.right(),r2.right()))
sright=CGALRS_SIGNAT(gcd,r1.right());
else
sright=CGALRS_SIGNAT(gcd,r2.right());
if(sleft!=sright)
return EQUAL;
else
return RS_COMPARE::compare_1_unequal/*<Gcd>*/(r1,r2);
}
} // namespace RS_COMPARE
} // namespace CGAL
#undef CGALRS_REFINE_N
#undef CGALRS_REFSTEPS
#undef CGALRS_SIGNAT
#endif // CGAL_RS_COMPARE_1_H