std::vector<std::pair<GaloisFieldDict, integer_class>>
GaloisFieldDict::gf_ddf_zassenhaus() const
{
unsigned i = 1;
GaloisFieldDict f(*this);
GaloisFieldDict g = GaloisFieldDict::from_vec({0_z, 1_z}, modulo_);
GaloisFieldDict to_sub(g);
std::vector<std::pair<GaloisFieldDict, integer_class>> factors;
auto b = f.gf_frobenius_monomial_base();
while (2 * i <= f.degree()) {
g = g.gf_frobenius_map(f, b);
GaloisFieldDict h = f.gf_gcd(g - to_sub);
if (not h.is_one()) {
factors.push_back({h, integer_class(i)});
f /= h;
g %= f;
b = f.gf_frobenius_monomial_base();
}
i += 1;
}
if (not(f.is_one() || f.empty())) {
factors.push_back({f, integer_class(f.degree())});
}
return factors;
}
std::vector<std::pair<GaloisFieldDict, integer_class>>
GaloisFieldDict::gf_sqf_list() const
{
std::vector<std::pair<GaloisFieldDict, integer_class>> vec_out;
if (degree() < 1)
return vec_out;
integer_class n = integer_class(1);
unsigned r = mp_get_si(modulo_);
bool sqf = false;
integer_class LC;
GaloisFieldDict f;
gf_monic(LC, outArg(f));
while (true) {
GaloisFieldDict F = f.gf_diff();
if (not F.dict_.empty()) {
GaloisFieldDict g = f.gf_gcd(F);
GaloisFieldDict h = f / g;
integer_class i = integer_class(1);
while (not h.is_one()) {
GaloisFieldDict G = h.gf_gcd(g);
GaloisFieldDict H = h / G;
if (H.degree() > 0)
vec_out.push_back({H, i * n});
i += integer_class(1);
g /= G;
h = G;
}
if (g.is_one())
sqf = true;
else
f = g;
}
if (not sqf) {
unsigned int deg = f.degree();
unsigned int d = deg / r;
GaloisFieldDict temp = f;
for (unsigned int i = 0; i <= d; i++) {
f.dict_[d - i] = temp.dict_[deg - i * r];
}
n *= r;
f.dict_.resize(d + 1);
f.gf_istrip();
} else
break;
}
return vec_out;
}
GaloisFieldDict GaloisFieldDict::gf_diff() const
{
auto df = degree();
GaloisFieldDict out = GaloisFieldDict({}, modulo_);
out.dict_.resize(df, integer_class(0));
for (unsigned i = 1; i <= df; i++) {
if (dict_[i] != integer_class(0)) {
out.dict_[i - 1] = i * dict_[i];
mp_fdiv_r(out.dict_[i - 1], out.dict_[i - 1], modulo_);
}
}
out.gf_istrip();
return out;
}
vec_basic GaloisField::get_args() const
{
vec_basic args;
if (poly_.dict_.empty())
args.push_back(zero);
else {
for (unsigned i = 0; i < poly_.dict_.size(); i++) {
if (poly_.dict_[i] == integer_class(0))
continue;
if (i == 0) {
args.push_back(integer(poly_.dict_[i]));
} else if (i == 1) {
if (poly_.dict_[i] == 1) {
args.push_back(var_);
} else {
args.push_back(
Mul::from_dict(integer(poly_.dict_[i]), {{var_, one}}));
}
} else {
if (poly_.dict_[i] == 1) {
args.push_back(pow(var_, integer(i)));
} else {
args.push_back(Mul::from_dict(integer(poly_.dict_[i]),
{{var_, integer(i)}}));
}
}
}
}
return args;
}
RCP<const UIntPolyFlint> UIntPolyFlint::from_vec(const RCP<const Symbol> &var,
const vec_integer_class &v)
{
// benchmark this against vec->str->fmpz_polyxx
unsigned int deg = v.size() - 1;
while (v[deg] == integer_class(0))
deg--;
fp_t f(deg + 1);
for (unsigned int i = 0; i <= deg; i++) {
if (v[i] != integer_class(0)) {
fz_t r(get_mpz_t(v[i]));
f.set_coeff(i, r);
}
}
return make_rcp<const UIntPolyFlint>(var, std::move(f));
}
void GaloisFieldDict::gf_monic(integer_class &res,
const Ptr<GaloisFieldDict> &monic) const
{
*monic = static_cast<GaloisFieldDict>(*this);
if (dict_.empty()) {
res = integer_class(0);
} else {
res = *dict_.rbegin();
if (res != integer_class(1)) {
integer_class inv, temp;
mp_invert(inv, res, modulo_);
for (auto &iter : monic->dict_) {
temp = inv;
temp *= iter;
mp_fdiv_r(iter, temp, modulo_);
}
}
}
}
GaloisFieldDict GaloisFieldDict::gf_lshift(const integer_class n) const
{
std::vector<integer_class> dict_out;
auto to_ret = GaloisFieldDict::from_vec(dict_out, modulo_);
if (!dict_.empty()) {
unsigned n_val = mp_get_si(n);
to_ret.dict_.resize(n_val, integer_class(0));
to_ret.dict_.insert(to_ret.dict_.end(), dict_.begin(), dict_.end());
}
return to_ret;
}
GaloisFieldDict GaloisFieldDict::gf_pow(const integer_class n) const
{
if (n == 0) {
return GaloisFieldDict({integer_class(1)}, modulo_);
}
if (n == 1)
return static_cast<GaloisFieldDict>(*this);
if (n == 2)
return gf_sqr();
long num = mp_get_si(n);
GaloisFieldDict to_sq = static_cast<GaloisFieldDict>(*this);
GaloisFieldDict to_ret = GaloisFieldDict({integer_class(1)}, modulo_);
while (1) {
if (num & 1) {
to_ret *= to_sq;
}
num >>= 1;
if (num == 0)
return to_ret;
to_sq = to_sq.gf_sqr();
}
}
RCP<const Number> Integer::pow_negint(const Integer &other) const
{
RCP<const Number> tmp = powint(*other.neg());
if (is_a<Integer>(*tmp)) {
const integer_class &j = down_cast<const Integer &>(*tmp).i;
#if SYMENGINE_INTEGER_CLASS == SYMENGINE_BOOSTMP
// boost::multiprecision::cpp_rational lacks an (int, cpp_int)
// constructor. must use cpp_rational(cpp_int,cpp_int)
rational_class q(integer_class(mp_sign(j)), mp_abs(j));
#else
rational_class q(mp_sign(j), mp_abs(j));
#endif
return Rational::from_mpq(std::move(q));
} else {
throw SymEngineException("powint returned non-integer");
}
}
RCP<const UnivariateIntPolynomial>
UnivariateIntPolynomial::from_dict(const RCP<const Symbol> &var,
map_uint_mpz &&d)
{
auto itter = d.begin();
while (itter != d.end()) {
if (integer_class(0) == itter->second) {
auto toErase = itter;
itter++;
d.erase(toErase);
} else {
itter++;
}
}
unsigned int degree = 0;
if (!d.empty())
degree = (--(d.end()))->first;
return make_rcp<const UnivariateIntPolynomial>(var, degree, std::move(d));
}
