virtual bool get_entry(size_t r, size_t c, ring_elem &result) const
// Returns false if (r,c) is out of range or if result is 0. No error
// is returned. result <-- this(r,c), and is set to zero if false is returned.
{
if (r >= 0 && r < n_rows() && c >= 0 && c < n_cols())
{
elem a;
mat.get_CoeffRing()->set_zero(a);
if (mat.get_entry(r,c,a))
{
mat.get_CoeffRing()->to_ring_elem(result,a);
return true;
}
}
result = mat.get_ring()->zero();
return false;
}
// Make a zero matrix, using the same ring and density taken from 'mat'.
MutableMat* makeZeroMatrix(size_t nrows, size_t ncols) const {
return zero_matrix(mat.get_ring(), &mat.ring(), nrows, ncols);
}
virtual const Ring * get_ring() const { return mat.get_ring(); }
