cgal/Polynomial/test/Polynomial/resultant.cpp

129 lines
3.7 KiB
C++

// currently using modular arithmetic is far to slow,
// that is, we use interpolation for multivariate resultants
// but no modular arithmetic.
// These are the defaults
//#define CGAL_RESULTANT_USE_MODULAR_ARITHMETIC 0
//#define CGAL_RESULTANT_USE_DECOMPOSE 1
#include <cassert>
#include <iostream>
#include <CGAL/Polynomial/resultant.h>
#include <CGAL/Arithmetic_kernel.h>
#include <CGAL/Residue.h>
#include <CGAL/Sqrt_extension.h>
#include <CGAL/Polynomial.h>
#include <CGAL/Polynomial_traits_d.h>
#include <CGAL/Random.h>
#include <CGAL/Timer.h>
#include <CGAL/gen_sparse_polynomial.h>
static CGAL::Random my_rnd(346); // some seed
template<class Polynomial_d>
void test_resultant(){
typedef typename CGAL::Polynomial_traits_d<Polynomial_d> PT;
typedef typename PT::Coefficient_type Coeff;
typename PT::Resultant resultant;
{
Polynomial_d A(0);
Polynomial_d B(0);
assert(resultant(A,B)==Coeff(0));
}{
Polynomial_d A(4);
Polynomial_d B(8);
assert(resultant(A,B)==Coeff(1));
}{
Polynomial_d A(4);
Polynomial_d B(Coeff(3), Coeff(5), Coeff(7));
assert(resultant(A,B)==Coeff(16)); // lcoeff(A)^degree(B)
}{
Polynomial_d f(Coeff(2),Coeff(7),Coeff(1),Coeff(8),Coeff(1),Coeff(8));
Polynomial_d g(Coeff(3),Coeff(1),Coeff(4),Coeff(1),Coeff(5),Coeff(9));
assert(resultant(f,g) == Coeff(230664271L)); // Maple
Polynomial_d h(Coeff(3),Coeff(4),Coeff(7),Coeff(7));
Polynomial_d fh(f*h);
Polynomial_d gh(g*h);
assert(resultant(fh,gh) == Coeff(0) );
}
for (int k = 0; k < 1; k++){
Polynomial_d F2 =
CGAL::generate_sparse_random_polynomial<Polynomial_d>(my_rnd,5);
Polynomial_d F1 =
CGAL::generate_sparse_random_polynomial<Polynomial_d>(my_rnd,5);
Coeff F = resultant(F1,F2); (void) F;
}
//std::cout << "end resultant: " << PT::d << std::endl;
}
#if CGAL_HAS_DEFAULT_ARITHMETIC_KERNEL
int main(){
// Set wrong rounding mode to test modular arithmetic
CGAL::Protect_FPU_rounding<true> pfr(CGAL_FE_UPWARD);
CGAL::IO::set_pretty_mode(std::cout);
typedef CGAL::Arithmetic_kernel AK;
typedef AK::Integer Integer;
typedef CGAL::Polynomial<Integer> Polynomial_1;
typedef CGAL::Polynomial<Polynomial_1> Polynomial_2;
typedef CGAL::Polynomial<Polynomial_2> Polynomial_3;
test_resultant<Polynomial_1>();
test_resultant<Polynomial_2>();
test_resultant<Polynomial_3>();
typedef CGAL::Polynomial<AK::Rational> RPolynomial_1;
typedef CGAL::Polynomial<RPolynomial_1> RPolynomial_2;
typedef CGAL::Polynomial<RPolynomial_2> RPolynomial_3;
test_resultant<RPolynomial_1>();
test_resultant<RPolynomial_2>();
test_resultant<RPolynomial_3>();
typedef CGAL::Sqrt_extension<AK::Integer, AK::Integer> EXT;
typedef CGAL::Polynomial<EXT> EPolynomial_1;
typedef CGAL::Polynomial<EPolynomial_1> EPolynomial_2;
typedef CGAL::Polynomial<EPolynomial_2> EPolynomial_3;
test_resultant<EPolynomial_1>();
test_resultant<EPolynomial_2>();
test_resultant<EPolynomial_3>();
typedef CGAL::Sqrt_extension<EXT, AK::Integer> EXT2;
typedef CGAL::Polynomial<EXT2> E2Polynomial_1;
test_resultant<E2Polynomial_1>();
// Enforce IEEE double precision and to nearest before using modular arithmetic
CGAL::Protect_FPU_rounding<true> pfr2(CGAL_FE_TONEAREST);
typedef CGAL::Polynomial<CGAL::Residue> MPolynomial_1;
typedef CGAL::Polynomial<MPolynomial_1> MPolynomial_2;
typedef CGAL::Polynomial<MPolynomial_2> MPolynomial_3;
test_resultant<MPolynomial_1>();
test_resultant<MPolynomial_2>();
test_resultant<MPolynomial_3>();
}
#else
int main(){
std::cout << " Test needs a default arithmetic kernel " << std::endl;
return 0;
}
#endif // CGAL_HAS_DEFAULT_ARITHMETIC_KERNEL