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#include "util.hpp"
#include "polyring.hpp"
#include "ring.hpp"
#include "monoid.hpp"
#include "qring.hpp"
#include "polyquotient.hpp"
#include "matrix.hpp"
#include "matrix-con.hpp"
#include "geopoly.hpp"
PolynomialRing::~PolynomialRing() {}
void PolynomialRing::setQuotientInfo(QRingInfo *qinfo0)
{
qinfo_ = qinfo0;
const PolyRing *numerR = getNumeratorRing(); // might be 'this'
for (int i = 0; i < n_quotients(); i++)
{
if (!numerR->is_homogeneous(quotient_element(i)))
{
setIsGraded(false);
break;
}
}
overZZ_ = (coeff_type_ == Ring::COEFF_ZZ);
}
void PolynomialRing::initialize_PolynomialRing(const Ring *K,
const Monoid *M,
const PolyRing *numeratorR,
const PolynomialRing *ambientR,
const Ring *denomR)
{
nvars_ = M->n_vars();
K_ = K;
M_ = M;
numerR_ = numeratorR;
ambientR_ = ambientR;
denomR_ = denomR;
exp_size = EXPONENT_BYTE_SIZE(nvars_);
if (K->is_QQ() || (K == globalZZ && denomR != 0))
coeff_type_ = Ring::COEFF_QQ;
else if (K == globalZZ && denomR == 0)
coeff_type_ = Ring::COEFF_ZZ;
else
coeff_type_ = Ring::COEFF_BASIC;
is_weyl_ = false;
is_solvable_ = false;
is_skew_ = false;
overZZ_ = false;
qinfo_ = new QRingInfo;
is_ZZ_quotient_ = false;
ZZ_quotient_value_ = ZERO_RINGELEM;
if (numeratorR != this)
{
// We must set the non-commutative settings ourselves at this time
if (numeratorR->cast_to_WeylAlgebra() != 0)
is_weyl_ = true;
else if (numeratorR->cast_to_SolvableAlgebra() != 0)
is_solvable_ = true;
else if (numeratorR->is_skew_commutative())
{
is_skew_ = true;
skew_ = numeratorR->getSkewInfo();
}
}
poly_size_ = 0; // The callee needs to set this later
gb_ring_ = 0; // The callee needs to set this later
// Also: callee should call setIsGraded, and set oneV, minus_oneV, zeroV
}
PolynomialRing *PolynomialRing::create_quotient(const PolynomialRing *R,
VECTOR(Nterm *) & elems)
// Grabs 'elems'. Each element of 'elems' should be in the ring R.
// They should also form a GB.
{
// Here are the cases:
// (1) R is a polynomial ring over a basic field
// (2) R is a polynomial ring over ZZ
// (3) R is a polynomial ring over QQ
// case (1), (2): PolyRingQuotient
// case (3): PolyQQ
PolynomialRing *result = NULL;
Ring::CoefficientType coeff_type = R->coefficient_type();
QRingInfo *qrinfo = NULL;
switch (coeff_type)
{
case COEFF_BASIC:
qrinfo = new QRingInfo_field_basic(R->getNumeratorRing(), elems);
result = new PolyRingQuotient;
break;
case COEFF_QQ:
qrinfo = new QRingInfo_field_QQ(R->getNumeratorRing(), elems);
result = new PolyRingQuotient;
break;
case COEFF_ZZ:
QRingInfo_ZZ *qrinfoZZ = new QRingInfo_ZZ(R->getNumeratorRing(), elems);
qrinfo = qrinfoZZ;
result = new PolyRingQuotient;
result->is_ZZ_quotient_ = qrinfoZZ->is_ZZ_quotient();
result->ZZ_quotient_value_ = qrinfoZZ->ZZ_quotient_value();
break;
}
result->initialize_ring(
R->characteristic(), R->get_degree_ring(), R->get_heft_vector());
result->initialize_PolynomialRing(R->getCoefficients(),
R->getMonoid(),
R->getNumeratorRing(),
R->getAmbientRing(),
R->getDenominatorRing());
result->gb_ring_ = R->get_gb_ring();
result->setQuotientInfo(qrinfo); // Also sets graded-ness
result->zeroV = result->from_long(0);
result->oneV = result->from_long(1);
result->minus_oneV = result->from_long(-1);
return result;
}
PolynomialRing *PolynomialRing::create_quotient(const PolynomialRing *R,
const Matrix *M)
{
if (M->get_ring() != R)
{
ERROR("quotient elements not in the expected polynomial ring");
return 0;
}
VECTOR(Nterm *) elems;
for (int i = 0; i < M->n_cols(); i++)
{
Nterm *f = R->numerator(M->elem(0, i));
elems.push_back(f);
}
for (int i = 0; i < R->n_quotients(); i++)
elems.push_back(R->quotient_element(i));
return create_quotient(R->getAmbientRing(), elems);
}
PolynomialRing *PolynomialRing::create_quotient(const PolynomialRing *R,
const PolynomialRing *B)
// R should be an ambient poly ring
// B should have: ambient of B is the logical coeff ring of R
// i.e. R = A[x], B = A/I
// return A[x]/I.
{
VECTOR(Nterm *) elems;
for (int i = 0; i < B->n_quotients(); i++)
{
ring_elem f;
R->promote(B->getNumeratorRing(), B->quotient_element(i), f);
elems.push_back(f);
}
return create_quotient(R, elems);
}
Matrix *PolynomialRing::getPresentation() const
{
const PolynomialRing *R = getAmbientRing();
MatrixConstructor mat(R->make_FreeModule(1), 0);
for (int i = 0; i < n_quotients(); i++)
// NEED: to make this into a fraction, if R has fractions.
mat.append(R->make_vec(0, quotient_element(i)));
return mat.to_matrix();
}
class SumCollectorPolyHeap : public SumCollector
{
polyheap H;
public:
SumCollectorPolyHeap(const PolynomialRing *R0) : H(R0) {}
~SumCollectorPolyHeap() {}
virtual void add(ring_elem f) { H.add(f); }
virtual ring_elem getValue() { return H.value(); }
};
SumCollector *PolynomialRing::make_SumCollector() const
{
return new SumCollectorPolyHeap(this);
}
unsigned int PolynomialRing::computeHashValue(const ring_elem a) const
{
unsigned int hash = 0;
unsigned int seed1 = 103;
unsigned int seed2 = 347654;
for (const Nterm *t = a.poly_val; t != 0; t = t->next)
{
unsigned int hash1 = getCoefficientRing()->computeHashValue(t->coeff);
unsigned int hash2 = getMonoid()->computeHashValue(t->monom);
hash += seed1 * hash1 + seed2 * hash2;
seed1 += 463633;
seed2 += 7858565;
}
return hash;
}
// Local Variables:
// compile-command: "make -C $M2BUILDDIR/Macaulay2/e "
// indent-tabs-mode: nil
// End:
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