diff --git a/src/sage/modular/quasimodform/element.py b/src/sage/modular/quasimodform/element.py index c1edff5a0b6..de8b13e2373 100644 --- a/src/sage/modular/quasimodform/element.py +++ b/src/sage/modular/quasimodform/element.py @@ -96,7 +96,6 @@ def __init__(self, parent, polynomial): raise ValueError("at least one coefficient is not a 'GradedModularFormElement'") self._polynomial = polynomial self._coefficients = polynomial.coefficients(sparse=False) - self.__base_ring = parent.base_ring() ModuleElement.__init__(self, parent) def q_expansion(self, prec=6): @@ -114,7 +113,7 @@ def q_expansion(self, prec=6): sage: E2.q_expansion(prec=10) 1 - 24*q - 72*q^2 - 96*q^3 - 168*q^4 - 144*q^5 - 288*q^6 - 192*q^7 - 360*q^8 - 312*q^9 + O(q^10) """ - E2 = eisenstein_series_qexp(2, prec=prec, K=self.__base_ring, normalization='constant') #normalization -> to force integer coefficients + E2 = eisenstein_series_qexp(2, prec=prec, K=self.base_ring(), normalization='constant') #normalization -> to force integer coefficients return sum(f.q_expansion(prec=prec)*E2**idx for idx, f in enumerate(self._coefficients)) qexp = q_expansion # alias @@ -318,7 +317,4 @@ def is_modular_form(self): sage: (QM.1 + QM.2).is_modular_form() # mixed weight components False """ - if not self._polynomial.degree(): - return self._polynomial[0].is_modular_form() - else: - return False + return not self._polynomial.degree() and self._polynomial[0].is_modular_form() diff --git a/src/sage/modular/quasimodform/ring.py b/src/sage/modular/quasimodform/ring.py index e6841a9b8c1..0e75f3811a2 100644 --- a/src/sage/modular/quasimodform/ring.py +++ b/src/sage/modular/quasimodform/ring.py @@ -164,7 +164,6 @@ def __init__(self, group=1, base_ring=QQ, name='E2'): raise NotImplementedError("base ring other than Q are not yet supported for quasimodular forms ring") self.__group = group - self.__base_ring = base_ring self.__modular_forms_subring = ModularFormsRing(group, base_ring) self.__polynomial_subring = self.__modular_forms_subring[name] Parent.__init__(self, base=base_ring, category=GradedAlgebras(base_ring)) @@ -191,21 +190,6 @@ def group(self): """ return self.__group - def base_ring(self): - r""" - Return the coefficient ring of this quasimodular forms ring. - - EXAMPLES:: - - sage: QuasiModularForms(1).base_ring() - Rational Field - sage: QuasiModularForms(1, GF(5)) - Traceback (most recent call last): - ... - NotImplementedError: base ring other than Q are not yet supported for quasimodular forms ring - """ - return self.__base_ring - def modular_forms_subring(self): r""" Return the subring of modular forms of this ring of quasimodular forms.