bool SchurRing2::initialize_SchurRing2()
{
initialize_ring(coefficientRing->characteristic());
zeroV = from_long(0);
oneV = from_long(1);
minus_oneV = from_long(-1);
SMinitialize(nvars,0);
return true;
}
bool RingZZ::initialize_ZZ(const PolynomialRing *deg_ring)
{
initialize_ring(0);
zeroV = from_long(0);
oneV = from_long(1);
minus_oneV = from_long(-1);
degree_ring = deg_ring;
coeffR = new M2::ARingZZGMP;
return true;
}
ring_elem RingZZ::invert(const ring_elem f) const
{
if (is_unit(f))
return copy(f);
else
return from_long(0);
}
bool Z_mod::initialize_Z_mod(int p)
{
initialize_ring(p);
P = p;
declare_field();
int i,j,q,n;
if (P==2)
_minus_one = 0;
else
_minus_one = (P-1)/2;
if (P==2)
_prim_root = 1;
else
{
j=1;
for (i=2; (i<P && j<P-1); i++)
for (q=i,j=1; (q!=1 && j<P); q=(q*i)%P,j++);
_prim_root = i-1;
}
// cerr << "z_mod_p: creating table for P = " << P << endl;
_log_table = newarray_atomic(int,P);
_exp_table = newarray_atomic(int,P);
for (i=0, n=1; i<P-1; i++, n=(n*_prim_root)%P)
{
_log_table[n] = i; // i = log_(base _prim_root)(n)
_exp_table[i] = n; // n = (_prim_root)^i
}
_ZERO = P-1;
_exp_table[_ZERO] = 0;
_log_table[0] = _ZERO;
_P1 = P-1;
zeroV = from_long(0);
oneV = from_long(1);
minus_oneV = from_long(-1);
coeffR = new CoefficientRingZZp(P,_log_table, _exp_table);
aringZZp = new M2::ARingZZp(P); // WARNING: this uses that the primitive element is the SAME as computed above!!
// Remove this warning once Z_mod is not in existence any longer.
return true;
}
v8::Handle<v8::Value> Session::onData(const v8::Arguments& args) {
fd_set fdset;
struct timeval timeout;
int block = 1;
int numfds = 0;
UNWRAP(Session, wrap, args.This());
SwapScope scope(wrap, args);
if(0 == wrap->session_) {
return ThrowError("Session hasn't opened.");
}
if(2 != args.Length()) {
return ThrowError("Must pass the msg and rinfo arguments to onData.");
}
FD_ZERO(&fdset);
/**
* block input: set to 1 if input timeout value is undefined
* set to 0 if input timeout value is defined
* block output: set to 1 if output timeout value is undefined
* set to 0 if output rimeout vlaue id defined
*/
if(1 != snmp_sess_select_info(wrap->session_, &numfds, &fdset,
&timeout, &block)) {
return v8::Undefined();
}
if(-1 == snmp_sess_read(wrap->session_, &fdset)) {
return ThrowError(snmp_api_errstring(wrap->arguments_.s_snmp_errno));
}
if(0 == block) {
v8::Handle<v8::Object> ret = v8::Object::New();
v8::Handle<v8::Object> timeout_v8 = v8::Object::New();
timeout_v8->Set(tv_sec_symbol, from_long(timeout.tv_sec));
timeout_v8->Set(tv_usec_symbol, from_long(timeout.tv_usec));
ret->Set(timeout_symbol, timeout_v8);
return scope.Close(ret);
} else {
return v8::Undefined();
}
}
bool GF::promote(const Ring *Rf, const ring_elem f, ring_elem &result) const
{
// Rf = Z/p[x]/F(x) ---> GF(p,n)
// promotion: need to be able to know the value of 'x'.
// lift: need to compute (primite_element)^e
if (Rf != _originalR) return false;
result = from_long(0);
int exp[1];
for (Nterm *t = f; t != NULL; t = t->next)
{
std::pair<bool,long> b = _originalR->getCoefficients()->coerceToLongInteger(t->coeff);
M2_ASSERT(b.first);
ring_elem coef = from_long(b.second);
_originalR->getMonoid()->to_expvector(t->monom, exp);
// exp[0] is the variable we want. Notice that since the ring is a quotient,
// this degree is < n (where Q_ = P^n).
ring_elem g = power(_x_exponent, exp[0]);
g = mult(g, coef);
internal_add_to(result, g);
}
return true;
}
bool GF::initialize_GF(const RingElement *prim)
{
// set the GF ring tables. Returns false if there is an error.
_primitive_element = prim;
_originalR = prim->get_ring()->cast_to_PolynomialRing();
initialize_ring(_originalR->characteristic(),
PolyRing::get_trivial_poly_ring());
declare_field();
int i,j;
if (_originalR->n_quotients() != 1)
{
ERROR("rawGaloisField expected an element of a quotient ring of the form ZZ/p[x]/(f)");
return false;
}
ring_elem f = _originalR->quotient_element(0);
Nterm *t = f;
int n = _originalR->getMonoid()->primary_degree(t->monom);
Q_ = static_cast<int>(characteristic());
for (i=1; i<n; i++) Q_ *= static_cast<int>(characteristic());
Qexp_ = n;
Q1_ = Q_-1;
_ZERO = 0;
_ONE = Q1_;
_MINUS_ONE = (characteristic() == 2 ? _ONE : Q1_/2);
// Get ready to create the 'one_table'
array<ring_elem> polys;
polys.append(_originalR->from_long(0));
ring_elem primelem = prim->get_value();
polys.append(_originalR->copy(primelem));
ring_elem oneR = _originalR->one();
_x_exponent = -1;
ring_elem x = _originalR->var(0);
if (_originalR->is_equal(primelem, x))
_x_exponent = 1;
for (i=2; i<Q_; i++)
{
ring_elem g = _originalR->mult(polys[i-1], primelem);
polys.append(g);
if (_originalR->is_equal(g, oneR)) break;
if (_originalR->is_equal(g, x))
_x_exponent = i;
}
if (polys.length() != Q_)
{
ERROR("GF: primitive element expected");
return false;
}
assert(_x_exponent >= 0);
// Set 'one_table'.
_one_table = newarray_atomic(int,Q_);
_one_table[0] = Q_-1;
for (i=1; i<=Q_-1; i++)
{
if (system_interrupted())
return false;
ring_elem f1 = _originalR->add(polys[i], oneR);
for (j=1; j<=Q_-1; j++)
if (_originalR->is_equal(f1, polys[j]))
break;
_one_table[i] = j;
}
// Create the Z/P ---> GF(Q) inclusion map
_from_int_table = newarray_atomic(int,characteristic());
int a = _ONE;
_from_int_table[0] = _ZERO;
for (i=1; i<characteristic(); i++)
{
_from_int_table[i] = a;
a = _one_table[a];
}
zeroV = from_long(0);
oneV = from_long(1);
minus_oneV = from_long(-1);
// M2::GaloisFieldTable G(*_originalR, primelem);
// G.display(std::cout);
return true;
}
ring_elem RingZZ::preferred_associate(ring_elem f) const
{
mpz_srcptr a = f.get_mpz();
if (mpz_sgn(a) >= 0) return from_long(1);
return from_long(-1);
}
