def _find_const_of_e4_e6_of_same_wt(k):
'''Returns an instance of ScalarModFormConst so that this corresponds to
a polynomial of es4 and es6 of weight k.
'''
a, b = [(a, b) for a, b, c, d in tuples_even_wt_modular_forms(k)
if c == d == 0][0]
return ScalarModFormConst([4] * a + [6] * b)
def _basis_const_base(self, ignored_dct):
'''This method is used for implmentation of _basis_const.
ignored_dct is a dictionary whose key is an element of self._gen_consts
and its value is a sub lift of [4, 6, 10, 12].
For exmaple if ignored_dct = {c: [4]} and F is a vector valued modular
form that corresponds to c, then
we do not use F * (a monomial including es4) when constructing a basis.
'''
wt_to_idx = {4: 0, 6: 1, 10: 2, 12: 3}
for c in self._gen_consts:
k = c.weight()
if c in ignored_dct:
idcs = [wt_to_idx[w] for w in ignored_dct[c]]
ts = [t for t in tuples_even_wt_modular_forms(self.wt - k)
if all(t[i] == 0 for i in idcs)]
else:
ts = tuples_even_wt_modular_forms(self.wt - k)
for t in _from_ts_wts(ts):
yield ConstMul(c, SMFC(t))
