if elt.parent().superalgebra() == self:
return elt.superalgebra_element()
- if hasattr(elt, 'column'):
- # Convert a vector into a column-matrix...
+ if hasattr(elt, 'sparse_vector'):
+ # Convert a vector into a column-matrix. We check for
+ # "sparse_vector" and not "column" because matrices also
+ # have a "column" method.
elt = elt.column()
if elt not in self.matrix_space():
# corresponding to trivial spaces (e.g. it returns only the
# eigenspace corresponding to lambda=1 if you take the
# decomposition relative to the identity element).
- trivial = self.subalgebra(())
+ trivial = self.subalgebra((), check_axioms=False)
J0 = trivial # eigenvalue zero
J5 = VectorSpace(self.base_ring(), 0) # eigenvalue one-half
J1 = trivial # eigenvalue one