FreeModule *value() {
if (symm1_result == 0)
{
symm1_result = F->get_ring()->make_FreeModule();
if (n >= 0)
{
symm1_deg = D->make_one();
symm1(0, n);
D->remove(symm1_deg);
}
}
return symm1_result;
}
SchreyerOrder *value() {
if (symm1_result == 0)
{
symm1_result = SchreyerOrder::create(M);
if (n >= 0)
{
symm1_base = M->make_one();
symm1(0, n);
M->remove(symm1_base);
}
}
return symm1_result;
}
void symm1(int lastn, // can use lastn..rank()-1 in product
int pow) const // remaining power to take
{
if (pow == 0)
symm1_result->append(symm1_deg);
else
{
for (int i=lastn; i<F->rank(); i++)
{
// increase symm1_deg, with e_i
D->mult(symm1_deg, F->degree(i), symm1_deg);
symm1(i, pow-1);
// decrease symm1_deg back
D->divide(symm1_deg, F->degree(i), symm1_deg);
}
}
}
void symm1(int lastn, // can use lastn..rank()-1 in product
int pow) // remaining power to take
{
if (pow == 0)
symm1_result->append(symm1_next++, symm1_base);
else
{
for (int i=lastn; i<S->rank(); i++)
{
// increase symm1_base with e_i
M->mult(symm1_base, S->base_monom(i), symm1_base);
symm1(i, pow-1);
// decrease symm1_base back
M->divide(symm1_base, S->base_monom(i), symm1_base);
}
}
}
