def centralizer_group_card(self, q=None): """ Return the cardinality of the centralizer group of a matrix of type ``self`` in a field of order ``q``. INPUT: ``q`` -- an integer or an indeterminate EXAMPLES:: sage: PT = PrimarySimilarityClassType(1, []) sage: PT.centralizer_group_card() 1 sage: PT = PrimarySimilarityClassType(2, [1, 1]) sage: PT.centralizer_group_card() q^8 - q^6 - q^4 + q^2 """ if q == None: R = FractionField(ZZ["q"]) q = R.gen() return self.statistic(centralizer_group_cardinality, q=q)
def centralizer_group_card(self, q=None): """ Return the cardinality of the centralizer group of a matrix of type ``self`` in a field of order ``q``. INPUT: ``q`` -- an integer or an indeterminate EXAMPLES:: sage: PT = PrimarySimilarityClassType(1, []) sage: PT.centralizer_group_card() 1 sage: PT = PrimarySimilarityClassType(2, [1, 1]) sage: PT.centralizer_group_card() q^8 - q^6 - q^4 + q^2 """ if q == None: R = FractionField(ZZ['q']) q = R.gen() return self.statistic(centralizer_group_cardinality, q=q)
class MFSeriesConstructor(SageObject,UniqueRepresentation): r""" Constructor for the Fourier expansion of some (specific, basic) modular forms. The constructor is used by forms elements in case their Fourier expansion is needed or requested. """ @staticmethod def __classcall__(cls, group = HeckeTriangleGroup(3), base_ring = ZZ, prec=ZZ(10), fix_d=False, set_d=None, d_num_prec=ZZ(53)): r""" Return a (cached) instance with canonical parameters. In particular in case ``fix_d = True`` or if ``set_d`` is set then the ``base_ring`` is replaced by the common parent of ``base_ring`` and the parent of ``set_d`` (resp. the numerical value of ``d`` in case ``fix_d=True``). EXAMPLES:: sage: MFSeriesConstructor() == MFSeriesConstructor(3, ZZ, 10, False, None, 53) True sage: MFSeriesConstructor(base_ring = CC, set_d=CC(1)) == MFSeriesConstructor(set_d=CC(1)) True sage: MFSeriesConstructor(group=4, fix_d=True).base_ring() == QQ True sage: MFSeriesConstructor(group=5, fix_d=True).base_ring() == RR True """ if (group==infinity): group = HeckeTriangleGroup(infinity) else: try: group = HeckeTriangleGroup(ZZ(group)) except TypeError: group = HeckeTriangleGroup(group.n()) prec=ZZ(prec) #if (prec<1): # raise Exception("prec must be an Integer >=1") fix_d = bool(fix_d) if (fix_d): n = group.n() d = group.dvalue() if (group.is_arithmetic()): d_num_prec = None set_d = 1/base_ring(1/d) else: d_num_prec = ZZ(d_num_prec) set_d = group.dvalue().n(d_num_prec) else: d_num_prec = None if (set_d is not None): base_ring=(base_ring(1)*set_d).parent() #elif (not base_ring.is_exact()): # raise NotImplementedError return super(MFSeriesConstructor,cls).__classcall__(cls, group, base_ring, prec, fix_d, set_d, d_num_prec) def __init__(self, group, base_ring, prec, fix_d, set_d, d_num_prec): r""" Constructor for the Fourier expansion of some (specific, basic) modular forms. INPUT: - ``group`` - A Hecke triangle group (default: HeckeTriangleGroup(3)). - ``base_ring`` - The base ring (default: ZZ) - ``prec`` - An integer (default: 10), the default precision used in calculations in the LaurentSeriesRing or PowerSeriesRing. - ``fix_d`` - ``True`` or ``False`` (default: ``False``). If ``fix_d == False`` the base ring of the power series is (the fraction field) of the polynomial ring over the base ring in one formal parameter ``d``. If ``fix_d == True`` the formal parameter ``d`` is replaced by its numerical value with numerical precision at least ``d_num_prec`` (or exact in case n=3, 4, 6). The base ring of the PowerSeriesRing or LaurentSeriesRing is changed to a common parent of ``base_ring`` and the parent of the mentioned value ``d``. - ``set_d`` - A number which replaces the formal parameter ``d``. The base ring of the PowerSeriesRing or LaurentSeriesRing is changed to a common parent of ``base_ring`` and the parent of the specified value for ``d``. Note that in particular ``set_d=1`` will produce rational Fourier expansions. - ``d_num_prec`` - An integer, a lower bound for the precision of the numerical value of ``d``. OUTPUT: The constructor for Fourier expansion with the specified settings. EXAMPLES:: sage: MFC = MFSeriesConstructor() sage: MFC Power series constructor for Hecke modular forms for n=3, base ring=Integer Ring with (basic series) precision 10 with formal parameter d sage: MFC.group() Hecke triangle group for n = 3 sage: MFC.prec() 10 sage: MFC.d().parent() Fraction Field of Univariate Polynomial Ring in d over Integer Ring sage: MFC._ZZseries_ring Power Series Ring in q over Rational Field sage: MFSeriesConstructor(set_d=CC(1)) Power series constructor for Hecke modular forms for n=3, base ring=Complex Field with 53 bits of precision with (basic series) precision 10 with parameter d=1.00000000000000 sage: MFSeriesConstructor(group=4, fix_d=True) Power series constructor for Hecke modular forms for n=4, base ring=Rational Field with (basic series) precision 10 with parameter d=1/256 sage: MFSeriesConstructor(group=5, fix_d=True) Power series constructor for Hecke modular forms for n=5, base ring=Real Field with 53 bits of precision with (basic series) precision 10 with parameter d=0.00705223418128563 """ self._group = group self._base_ring = base_ring self._prec = prec self._fix_d = fix_d self._set_d = set_d self._d_num_prec = d_num_prec if (set_d): self._coeff_ring = FractionField(base_ring) self._d = set_d else: self._coeff_ring = FractionField(PolynomialRing(base_ring,"d")) self._d = self._coeff_ring.gen() self._ZZseries_ring = PowerSeriesRing(QQ,'q',default_prec=self._prec) self._qseries_ring = PowerSeriesRing(self._coeff_ring,'q',default_prec=self._prec) def _repr_(self): r""" Return the string representation of ``self``. EXAMPLES:: sage: MFSeriesConstructor(group=4, fix_d=True) Power series constructor for Hecke modular forms for n=4, base ring=Rational Field with (basic series) precision 10 with parameter d=1/256 sage: MFSeriesConstructor(group=5) Power series constructor for Hecke modular forms for n=5, base ring=Integer Ring with (basic series) precision 10 with formal parameter d """ if (self._set_d): return "Power series constructor for Hecke modular forms for n={}, base ring={} with (basic series) precision {} with parameter d={}".\ format(self._group.n(), self._base_ring, self._prec, self._d) else: return "Power series constructor for Hecke modular forms for n={}, base ring={} with (basic series) precision {} with formal parameter d".\ format(self._group.n(), self._base_ring, self._prec) def group(self): r""" Return the (Hecke triangle) group of ``self``. EXAMPLES:: sage: MFSeriesConstructor(group=4, fix_d=True).group() Hecke triangle group for n = 4 """ return self._group def hecke_n(self): r""" Return the parameter ``n`` of the (Hecke triangle) group of ``self``. EXAMPLES:: sage: MFSeriesConstructor(group=4, fix_d=True).hecke_n() 4 """ return self._group.n() def base_ring(self): r""" Return base ring of ``self``. EXAMPLES:: sage: MFSeriesConstructor(group=5, fix_d=True).base_ring() Real Field with 53 bits of precision sage: MFSeriesConstructor(group=5, fix_d=True, d_num_prec=100).base_ring() Real Field with 100 bits of precision """ return self._base_ring def prec(self): r""" Return the used default precision for the PowerSeriesRing or LaurentSeriesRing. EXAMPLES:: sage: MFSeriesConstructor(group=5, fix_d=True).prec() 10 sage: MFSeriesConstructor(group=5, prec=20).prec() 20 """ return self._prec def fix_d(self): r""" Return whether the numerical value for the parameter ``d`` will be substituted or not. Note: Depending on whether ``set_d`` is ``None`` or not ``d`` might still be substituted despite ``fix_d`` being ``False``. EXAMPLES:: sage: MFSeriesConstructor(group=5, fix_d=True, set_d=1).fix_d() True sage: MFSeriesConstructor(group=5, fix_d=True, set_d=1).set_d() 0.00705223418128563 sage: MFSeriesConstructor(group=5, set_d=1).fix_d() False """ return self._fix_d def set_d(self): r""" Return the numerical value which is substituted for the parameter ``d``. Default: ``None``, meaning the formal parameter ``d`` is used. EXAMPLES:: sage: MFSeriesConstructor(group=5, fix_d=True, set_d=1).set_d() 0.00705223418128563 sage: MFSeriesConstructor(group=5, set_d=1).set_d() 1 sage: MFSeriesConstructor(group=5, set_d=1).set_d().parent() Integer Ring """ return self._set_d def is_exact(self): r""" Return whether used ``base_ring`` is exact. EXAMPLES:: sage: MFSeriesConstructor(group=4, fix_d=True).is_exact() True sage: MFSeriesConstructor(group=5, fix_d=True).is_exact() False sage: MFSeriesConstructor(group=5, set_d=1).is_exact() True """ return self._base_ring.is_exact() def d(self): r""" Return the formal parameter ``d`` respectively its (possibly numerical) value in case ``set_d`` is not ``None``. EXAMPLES:: sage: MFSeriesConstructor(group=4, fix_d=True).d() 1/256 sage: MFSeriesConstructor(group=4).d() d sage: MFSeriesConstructor(group=4).d().parent() Fraction Field of Univariate Polynomial Ring in d over Integer Ring sage: MFSeriesConstructor(group=5, fix_d=True).d() 0.00705223418128563 sage: MFSeriesConstructor(group=5, set_d=1).d() 1 """ return self._d def q(self): r""" Return the generator of the used PowerSeriesRing. EXAMPLES:: sage: MFSeriesConstructor(group=4, fix_d=True).q() q sage: MFSeriesConstructor(group=4, fix_d=True).q().parent() Power Series Ring in q over Rational Field sage: MFSeriesConstructor(group=5, fix_d=True).q().parent() Power Series Ring in q over Real Field with 53 bits of precision """ return self._qseries_ring.gen() def coeff_ring(self): r""" Return coefficient ring of ``self``. EXAMPLES:: sage: MFSeriesConstructor(group=4, fix_d=True).coeff_ring() Rational Field sage: MFSeriesConstructor(group=4).coeff_ring() Fraction Field of Univariate Polynomial Ring in d over Integer Ring sage: MFSeriesConstructor(group=5, fix_d=True).coeff_ring() Real Field with 53 bits of precision sage: MFSeriesConstructor(group=5).coeff_ring() Fraction Field of Univariate Polynomial Ring in d over Integer Ring """ return self._coeff_ring def qseries_ring(self): r""" Return the used PowerSeriesRing. EXAMPLES:: sage: MFSeriesConstructor(group=4, fix_d=True).qseries_ring() Power Series Ring in q over Rational Field sage: MFSeriesConstructor(group=4).qseries_ring() Power Series Ring in q over Fraction Field of Univariate Polynomial Ring in d over Integer Ring sage: MFSeriesConstructor(group=5, fix_d=True).qseries_ring() Power Series Ring in q over Real Field with 53 bits of precision sage: MFSeriesConstructor(group=5).qseries_ring() Power Series Ring in q over Fraction Field of Univariate Polynomial Ring in d over Integer Ring """ return self._qseries_ring @cached_method def J_inv_ZZ(self): r""" Return the rational Fourier expansion of ``J_inv``, where ``d`` is replaced by ``1``. This is the main function used to determine all Fourier expansions! EXAMPLES:: sage: MFSeriesConstructor(prec=3).J_inv_ZZ() q^-1 + 31/72 + 1823/27648*q + O(q^2) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).J_inv_ZZ() q^-1 + 79/200 + 42877/640000*q + O(q^2) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).J_inv_ZZ().parent() Laurent Series Ring in q over Rational Field """ F1 = lambda a,b: self._ZZseries_ring(\ [ ZZ(0) ] + [\ rising_factorial(a,k) * rising_factorial(b,k) / (ZZ(k).factorial())**2 * sum([\ ZZ(1)/(a+j)+ZZ(1)/(b+j)-ZZ(2)/ZZ(1+j) for j in range(ZZ(0),ZZ(k))\ ]) for k in range(ZZ(1),ZZ(self._prec+1)) ], ZZ(self._prec+1)\ ) F = lambda a,b,c: self._ZZseries_ring([\ rising_factorial(a,k) * rising_factorial(b,k) / rising_factorial(c,k) / (ZZ(k).factorial())\ for k in range(ZZ(0),ZZ(self._prec+1))\ ], ZZ(self._prec+1)) a = self._group.alpha() b = self._group.beta() Phi = F1(a,b) / F(a,b,ZZ(1)) q = self._ZZseries_ring.gen() J_inv_ZZ = ZZ(1) / ((q*Phi.exp()).reversion()) return J_inv_ZZ @cached_method def J_inv(self): r""" Return the Fourier expansion of ``J_inv``. EXAMPLES:: sage: MFSeriesConstructor(prec=3, fix_d=True).J_inv() 1/1728*q^-1 + 31/72 + 1823/16*q + O(q^2) sage: MFSeriesConstructor(prec=3).J_inv_ZZ() == MFSeriesConstructor(prec=3, set_d=1).J_inv() True sage: MFSeriesConstructor(group=5, prec=3).J_inv() d*q^-1 + 79/200 + 42877/(640000*d)*q + O(q^2) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).J_inv() 0.00705223418128563*q^-1 + 0.395000000000000 + 9.49987064777062*q + O(q^2) sage: MFSeriesConstructor(group=5, prec=3).J_inv().parent() Laurent Series Ring in q over Fraction Field of Univariate Polynomial Ring in d over Integer Ring sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).J_inv().parent() Laurent Series Ring in q over Real Field with 53 bits of precision """ return self.J_inv_ZZ()(self._qseries_ring.gen()/self._d) @cached_method def F_rho_ZZ(self): r""" Return the rational Fourier expansion of ``F_rho``, where ``d`` is replaced by ``1``. EXAMPLES:: sage: MFSeriesConstructor(prec=3).F_rho_ZZ() 1 + 5/36*q + 5/6912*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).F_rho_ZZ() 1 + 7/100*q + 21/160000*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).F_rho_ZZ().parent() Power Series Ring in q over Rational Field """ q = self._ZZseries_ring.gen() n = self.hecke_n() temp_expr = ((-q*self.J_inv_ZZ().derivative())**2/(self.J_inv_ZZ()*(self.J_inv_ZZ()-1))).power_series() F_rho_ZZ = (temp_expr.log()/(n-2)).exp() return F_rho_ZZ @cached_method def F_rho(self): r""" Return the Fourier expansion of ``F_rho``. EXAMPLES:: sage: MFSeriesConstructor(prec=3, fix_d=True).F_rho() 1 + 240*q + 2160*q^2 + O(q^3) sage: MFSeriesConstructor(prec=3).F_rho_ZZ() == MFSeriesConstructor(prec=3, set_d=1).F_rho() True sage: MFSeriesConstructor(group=5, prec=3).F_rho() 1 + 7/(100*d)*q + 21/(160000*d^2)*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).F_rho() 1.00000000000000 + 9.92593243510795*q + 2.63903932249093*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3).F_rho().parent() Power Series Ring in q over Fraction Field of Univariate Polynomial Ring in d over Integer Ring sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).F_rho().parent() Power Series Ring in q over Real Field with 53 bits of precision """ return self.F_rho_ZZ()(self._qseries_ring.gen()/self._d) @cached_method def F_i_ZZ(self): r""" Return the rational Fourier expansion of ``F_i``, where ``d`` is replaced by ``1``. EXAMPLES:: sage: MFSeriesConstructor(prec=3).F_i_ZZ() 1 - 7/24*q - 77/13824*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).F_i_ZZ() 1 - 13/40*q - 351/64000*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).F_i_ZZ().parent() Power Series Ring in q over Rational Field """ q = self._ZZseries_ring.gen() n = self.hecke_n() temp_expr = ((-q*self.J_inv_ZZ().derivative())**n/(self.J_inv_ZZ()**(n-1)*(self.J_inv_ZZ()-1))).power_series() F_i_ZZ = (temp_expr.log()/(n-2)).exp() return F_i_ZZ @cached_method def F_i(self): r""" Return the Fourier expansion of ``F_i``. EXAMPLES:: sage: MFSeriesConstructor(prec=3, fix_d=True).F_i() 1 - 504*q - 16632*q^2 + O(q^3) sage: MFSeriesConstructor(prec=3).F_i_ZZ() == MFSeriesConstructor(prec=3, set_d=1).F_i() True sage: MFSeriesConstructor(group=5, prec=3).F_i() 1 - 13/(40*d)*q - 351/(64000*d^2)*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).F_i() 1.00000000000000 - 46.0846863058583*q - 110.274143118371*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3).F_i().parent() Power Series Ring in q over Fraction Field of Univariate Polynomial Ring in d over Integer Ring sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).F_i().parent() Power Series Ring in q over Real Field with 53 bits of precision """ return self.F_i_ZZ()(self._qseries_ring.gen()/self._d) @cached_method def F_inf_ZZ(self): r""" Return the rational Fourier expansion of ``F_inf``, where ``d`` is replaced by ``1``. EXAMPLES:: sage: MFSeriesConstructor(prec=3).F_inf_ZZ() q - 1/72*q^2 + 7/82944*q^3 + O(q^4) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).F_inf_ZZ() q - 9/200*q^2 + 279/640000*q^3 + O(q^4) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).F_inf_ZZ().parent() Power Series Ring in q over Rational Field """ q = self._ZZseries_ring.gen() n = self.hecke_n() temp_expr = ((-q*self.J_inv_ZZ().derivative())**(2*n)/(self.J_inv_ZZ()**(2*n-2)*(self.J_inv_ZZ()-1)**n)/q**(n-2)).power_series() F_inf_ZZ = (temp_expr.log()/(n-2)).exp()*q return F_inf_ZZ @cached_method def F_inf(self): r""" Return the Fourier expansion of ``F_inf``. EXAMPLES:: sage: MFSeriesConstructor(prec=3, fix_d=True).F_inf() q - 24*q^2 + 252*q^3 + O(q^4) sage: MFSeriesConstructor(prec=3).F_inf_ZZ() == MFSeriesConstructor(prec=3, set_d=1).F_inf() True sage: MFSeriesConstructor(group=5, prec=3).F_inf() q - 9/(200*d)*q^2 + 279/(640000*d^2)*q^3 + O(q^4) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).F_inf() 0.000000000000000 + 1.00000000000000*q - 6.38095656542654*q^2 + 8.76538060684488*q^3 + O(q^4) sage: MFSeriesConstructor(group=5, prec=3).F_inf().parent() Power Series Ring in q over Fraction Field of Univariate Polynomial Ring in d over Integer Ring sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).F_inf().parent() Power Series Ring in q over Real Field with 53 bits of precision """ return self._d*self.F_inf_ZZ()(self._qseries_ring.gen()/self._d) @cached_method def G_inv_ZZ(self): r""" Return the rational Fourier expansion of ``G_inv``, where ``d`` is replaced by ``1``. EXAMPLES:: sage: MFSeriesConstructor(group=4, prec=3).G_inv_ZZ() q^-1 - 3/32 - 955/16384*q + O(q^2) sage: MFSeriesConstructor(group=8, prec=3, fix_d=True).G_inv_ZZ() q^-1 - 15/128 - 15139/262144*q + O(q^2) sage: MFSeriesConstructor(group=8, prec=3, fix_d=True).G_inv_ZZ().parent() Laurent Series Ring in q over Rational Field """ n = self.hecke_n() if (ZZ(2).divides(n)): return self.F_i_ZZ()*(self.F_rho_ZZ()**(ZZ(n/ZZ(2))))/self.F_inf_ZZ() else: #return self._qseries_ring([]) raise Exception("G_inv doesn't exist for n={}.".format(self.hecke_n())) @cached_method def G_inv(self): r""" Return the Fourier expansion of ``G_inv``. EXAMPLES:: sage: MFSeriesConstructor(group=4, prec=3, fix_d=True).G_inv() 1/16777216*q^-1 - 3/2097152 - 955/4194304*q + O(q^2) sage: MFSeriesConstructor(group=4, prec=3).G_inv_ZZ() == MFSeriesConstructor(group=4, prec=3, set_d=1).G_inv() True sage: MFSeriesConstructor(group=8, prec=3).G_inv() d^3*q^-1 - 15*d^2/128 - 15139*d/262144*q + O(q^2) sage: MFSeriesConstructor(group=8, prec=3, fix_d=True).G_inv() 1.64838830030189e-6*q^-1 - 0.0000163526310530017 - 0.000682197999433738*q + O(q^2) sage: MFSeriesConstructor(group=8, prec=3).G_inv().parent() Laurent Series Ring in q over Fraction Field of Univariate Polynomial Ring in d over Integer Ring sage: MFSeriesConstructor(group=8, prec=3, fix_d=True).G_inv().parent() Laurent Series Ring in q over Real Field with 53 bits of precision """ return (self._d)**2*self.G_inv_ZZ()(self._qseries_ring.gen()/self._d) @cached_method def E4_ZZ(self): r""" Return the rational Fourier expansion of ``E_4``, where ``d`` is replaced by ``1``. EXAMPLES:: sage: MFSeriesConstructor(prec=3).E4_ZZ() 1 + 5/36*q + 5/6912*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).E4_ZZ() 1 + 21/100*q + 483/32000*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).E4_ZZ().parent() Power Series Ring in q over Rational Field """ q = self._ZZseries_ring.gen() E4_ZZ = ((-q*self.J_inv_ZZ().derivative())**2/(self.J_inv_ZZ()*(self.J_inv_ZZ()-1))).power_series() return E4_ZZ @cached_method def E4(self): r""" Return the Fourier expansion of ``E_4``. EXAMPLES:: sage: MFSeriesConstructor(prec=3, fix_d=True).E4() 1 + 240*q + 2160*q^2 + O(q^3) sage: MFSeriesConstructor(prec=3).E4_ZZ() == MFSeriesConstructor(prec=3, set_d=1).E4() True sage: MFSeriesConstructor(group=5, prec=3).E4() 1 + 21/(100*d)*q + 483/(32000*d^2)*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).E4() 1.00000000000000 + 29.7777973053239*q + 303.489522086457*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3).E4().parent() Power Series Ring in q over Fraction Field of Univariate Polynomial Ring in d over Integer Ring sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).E4().parent() Power Series Ring in q over Real Field with 53 bits of precision """ return self.E4_ZZ()(self._qseries_ring.gen()/self._d) @cached_method def E6_ZZ(self): r""" Return the rational Fourier expansion of ``E_6``, where ``d`` is replaced by ``1``. EXAMPLES:: sage: MFSeriesConstructor(prec=3).E6_ZZ() 1 - 7/24*q - 77/13824*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).E6_ZZ() 1 - 37/200*q - 14663/320000*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).E6_ZZ().parent() Power Series Ring in q over Rational Field """ q = self._ZZseries_ring.gen() n = self.hecke_n() E6_ZZ = ((-q*self.J_inv_ZZ().derivative())**3/(self.J_inv_ZZ()**2*(self.J_inv_ZZ()-1))).power_series() return E6_ZZ @cached_method def E6(self): r""" Return the Fourier expansion of ``E_6``. EXAMPLES:: sage: MFSeriesConstructor(prec=3, fix_d=True).E6() 1 - 504*q - 16632*q^2 + O(q^3) sage: MFSeriesConstructor(prec=3).E6_ZZ() == MFSeriesConstructor(prec=3, set_d=1).E6() True sage: MFSeriesConstructor(group=5, prec=3).E6() 1 - 37/(200*d)*q - 14663/(320000*d^2)*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).E6() 1.00000000000000 - 26.2328214356424*q - 921.338894897250*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3).E6().parent() Power Series Ring in q over Fraction Field of Univariate Polynomial Ring in d over Integer Ring sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).E6().parent() Power Series Ring in q over Real Field with 53 bits of precision """ return self.E6_ZZ()(self._qseries_ring.gen()/self._d) @cached_method def Delta_ZZ(self): r""" Return the rational Fourier expansion of ``Delta``, where ``d`` is replaced by ``1``. EXAMPLES:: sage: MFSeriesConstructor(prec=3).Delta_ZZ() q - 1/72*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).Delta_ZZ() 71/50*q + 28267/16000*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).Delta_ZZ().parent() Power Series Ring in q over Rational Field """ n = self.hecke_n() return self.E4_ZZ()**(2*n-6)*(self.E4_ZZ()**n-self.E6_ZZ()**2) @cached_method def Delta(self): r""" Return the Fourier expansion of ``Delta``. EXAMPLES:: sage: MFSeriesConstructor(prec=3, fix_d=True).Delta() q - 24*q^2 + O(q^3) sage: MFSeriesConstructor(prec=3).Delta_ZZ() == MFSeriesConstructor(prec=3, set_d=1).Delta() True sage: MFSeriesConstructor(group=5, prec=3).Delta() 71/50*q + 28267/(16000*d)*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).Delta() 0.000000000000000 + 1.42000000000000*q + 250.514582270711*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3).Delta().parent() Power Series Ring in q over Fraction Field of Univariate Polynomial Ring in d over Integer Ring sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).Delta().parent() Power Series Ring in q over Real Field with 53 bits of precision """ return (self._d)*self.Delta_ZZ()(self._qseries_ring.gen()/self._d) @cached_method def E2_ZZ(self): r""" Return the rational Fourier expansion of ``E2``, where ``d`` is replaced by ``1``. EXAMPLES:: sage: MFSeriesConstructor(prec=3).E2_ZZ() 1 - 1/72*q - 1/41472*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).E2_ZZ() 1 - 9/200*q - 369/320000*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).E2_ZZ().parent() Power Series Ring in q over Rational Field """ q = self._ZZseries_ring.gen() E2_ZZ = (q*self.F_inf_ZZ().derivative())/self.F_inf_ZZ() return E2_ZZ @cached_method def E2(self): r""" Return the Fourier expansion of ``E2``. EXAMPLES:: sage: MFSeriesConstructor(prec=3, fix_d=True).E2() 1 - 24*q - 72*q^2 + O(q^3) sage: MFSeriesConstructor(prec=3).E2_ZZ() == MFSeriesConstructor(prec=3, set_d=1).E2() True sage: MFSeriesConstructor(group=5, prec=3).E2() 1 - 9/(200*d)*q - 369/(320000*d^2)*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).E2() 1.00000000000000 - 6.38095656542654*q - 23.1858454761703*q^2 + O(q^3) sage: MFSeriesConstructor(group=5, prec=3).E2().parent() Power Series Ring in q over Fraction Field of Univariate Polynomial Ring in d over Integer Ring sage: MFSeriesConstructor(group=5, prec=3, fix_d=True).E2().parent() Power Series Ring in q over Real Field with 53 bits of precision """ return self.E2_ZZ()(self._qseries_ring.gen()/self._d)