tensor()

FreeModule * FreeModule::tensor

(

const FreeModule *

G

)

const

Definition at line 271 of file freemod.cpp.

{
  if (R != G->get_ring())
    {
      ERROR("expected free modules over the same ring");
      return nullptr;
    }
  auto D = R->degree_monoid();
  FreeModule *result = new_free();
  monomial deg = D->make_one();
 
  for (int i = 0; i < rank(); i++)
    for (int j = 0; j < G->rank(); j++)
      {
        D->mult(degree(i), G->degree(j), deg);
        result->append(deg);
      }
 
  D->remove(deg);
  if (schreyer != nullptr && G->schreyer != nullptr)
    result->schreyer = schreyer->tensor(G->schreyer);
  return result;
}

References degree(), ERROR, FreeModule(), G, monomial, new_free(), R, rank(), result(), and schreyer.

Referenced by Matrix::diff(), Matrix::flip(), IM2_FreeModule_tensor(), Matrix::module_tensor(), and Matrix::wedge_product().