static
void RecEDF(vec_GF2X& factors, const GF2X& f, long d)
{
if (deg(f) == d) {
append(factors, f);
return;
}
GF2X f1, f2;
EDFSplit(f1, f2, f, d);
RecEDF(factors, f1, d);
RecEDF(factors, f2, d);
}
void EDF(vec_GF2X& factors, const GF2X& ff, long d, long verbose)
{
GF2X f = ff;
if (IsZero(f)) Error("EDF: bad args");
long n = deg(f);
long r = n/d;
if (r == 0) {
factors.SetLength(0);
return;
}
if (r == 1) {
factors.SetLength(1);
factors[0] = f;
return;
}
if (d == 1) {
// factors are X and X+1
factors.SetLength(2);
SetX(factors[0]);
SetX(factors[1]);
SetCoeff(factors[1], 0);
return;
}
double t;
if (verbose) {
cerr << "computing EDF(" << d << "," << r << ")...";
t = GetTime();
}
factors.SetLength(0);
RecEDF(factors, f, d);
if (verbose) cerr << (GetTime()-t) << "\n";
}
void EDF(vec_ZZ_pEX& factors, const ZZ_pEX& ff, const ZZ_pEX& bb,
long d, long verbose)
{
ZZ_pEX f = ff;
ZZ_pEX b = bb;
if (!IsOne(LeadCoeff(f)))
LogicError("EDF: bad args");
long n = deg(f);
long r = n/d;
if (r == 0) {
factors.SetLength(0);
return;
}
if (r == 1) {
factors.SetLength(1);
factors[0] = f;
return;
}
if (d == 1) {
RootEDF(factors, f, verbose);
return;
}
double t;
if (verbose) {
cerr << "computing EDF(" << d << "," << r << ")...";
t = GetTime();
}
factors.SetLength(0);
RecEDF(factors, f, b, d, verbose);
if (verbose) cerr << (GetTime()-t) << "\n";
}
void RecEDF(vec_ZZ_pEX& factors, const ZZ_pEX& f, const ZZ_pEX& b, long d,
long verbose)
{
vec_ZZ_pEX v;
long i;
ZZ_pEX bb;
if (verbose) cerr << "+";
EDFSplit(v, f, b, d);
for (i = 0; i < v.length(); i++) {
if (deg(v[i]) == d) {
append(factors, v[i]);
}
else {
ZZ_pEX bb;
rem(bb, b, v[i]);
RecEDF(factors, v[i], bb, d, verbose);
}
}
}
