def fix1_qcurve_flag(ec, verbose=False):
"""
Update ec structure (from nfcurves collection) with the correct
q_curves flag. For degree >2 at present we only do trivial tests
here which do not require any computation.
"""
if ec['q_curve']: # keep old True values
return ec
# Easy sufficient tests in all degrees
qc = False
if ec['cm']:
qc = True
elif all(c == '0' for c in ec['jinv'].split(",")[1:]):
qc = True
if qc: # then we have just set it to True
if ec['q_curve'] != qc:
if verbose:
print("{}: changing q_curve flag from {} to {}".format(
ec['label'], ec['q_curve'], qc))
ec['q_curve'] = qc
return ec
# else if degree != 2 just replace possibly false negatives with '?'
if ec['degree'] > 2:
qc = '?'
# if ec['q_curve'] != qc:
# print("{}: changing q_curve flag from {} to {}".format(ec['label'],ec['q_curve'],qc))
ec['q_curve'] = qc
return ec
# else (degree 2 only for now) do the work (knowing that E does
# not have CM and j(E) is not in Q)
K = FIELD(ec['field_label'])
sigma = K.K().galois_group()[1]
# Compute the Q-curve flag from scratch
N = ideal_from_string(K.K(), ec['conductor_ideal'])
if sigma(N) != N:
qc = False
else: # construct and check the curve
ainvsK = parse_ainvs(K.K(), ec['ainvs'])
E = EllipticCurve(ainvsK)
qc = is_Q_curve(E)
if ec['q_curve'] != qc:
if verbose:
print("{}: changing q_curve flag from {} to {}".format(
ec['label'], ec['q_curve'], qc))
ec['q_curve'] = qc
return ec
def check_Q_curves(field_label='2.2.5.1',
min_norm=0,
max_norm=None,
fix=False,
verbose=False):
"""Given a (quadratic) field label test all curves E over that field for being Q-curves.
"""
query = {}
query['field_label'] = field_label
query['conductor_norm'] = {'$gte': int(min_norm)}
if max_norm:
query['conductor_norm']['$lte'] = int(max_norm)
else:
max_norm = 'infinity'
cursor = nfcurves.find(query)
# keep the curves and re-find them, else the cursor times out.
curves = [ec['label'] for ec in cursor]
ncurves = len(curves)
print("Checking {} curves over field {}".format(ncurves, field_label))
K = FIELD(field_label)
sigma = K.K().galois_group()[1]
bad1 = []
bad2 = []
count = 0
for label in curves:
count += 1
if count % 1000 == 0:
print("checked {} curves ({}%)".format(count,
100.0 * count / ncurves))
ec = nfcurves.find_one({'label': label})
assert label == ec['label']
method = None
# first check that j(E) is rational (no computation needed)
jinv = ec['jinv']
if all(c == '0' for c in jinv.split(",")[1:]):
if verbose: print("{}: j in QQ".format(label))
qc = True
method = "j in Q"
elif ec['cm']:
if verbose: print("{}: CM".format(label))
qc = True
method = "CM"
else: # construct and check the conductor
if verbose:
print("{}: checking conductor".format(label))
N = ideal_from_string(K.K(), ec['conductor_ideal'])
if sigma(N) != N:
qc = False
method = "conductor"
else: # construct and check the curve
if verbose:
print("{}: checking isogenies".format(label))
ainvsK = parse_ainvs(K.K(), ec['ainvs'])
E = EllipticCurve(ainvsK)
qc = is_Q_curve(E)
method = "isogenies"
db_qc = ec['q_curve']
if qc and not db_qc:
print("Curve {} is a Q-curve (using {}) but database thinks not".
format(label, method))
bad1 += [label]
elif db_qc and not qc:
print(
"Curve {} is not a Q-curve (using {}) but database thinks it is"
.format(label, method))
bad2 += [label]
else:
if verbose:
print("Curve {} OK (using {})".format(label, method))
print(
"{} curves in the database are incorrectly labelled as being Q-curves".
format(len(bad2)))
print(
"{} curves in the database are incorrectly labelled as NOT being Q-curves"
.format(len(bad1)))
return bad1, bad2
class WebBMF(object):
"""
Class for an Bianchi Newform
"""
def __init__(self, dbdata):
"""Arguments:
- dbdata: the data from the database
dbdata is expected to be a database entry from which the class
is initialised.
"""
logger.debug("Constructing an instance of WebBMF class from database")
self.__dict__.update(dbdata)
# All other fields are handled here
self.make_form()
@staticmethod
def by_label(label):
"""
Searches for a specific Hilbert newform in the forms
collection by its label.
"""
data = db.bmf_forms.lookup(label)
if data:
return WebBMF(data)
raise ValueError("Bianchi newform %s not found" % label)
# caller must catch this and raise an error
def make_form(self):
# To start with the data fields of self are just those from
# the database. We need to reformat these and compute some
# further (easy) data about it.
#
from lmfdb.ecnf.WebEllipticCurve import FIELD
self.field = FIELD(self.field_label)
pretty_field = field_pretty(self.field_label)
self.field_knowl = nf_display_knowl(self.field_label, pretty_field)
try:
dims = db.bmf_dims.lucky(
{
'field_label': self.field_label,
'level_label': self.level_label
},
projection='gl2_dims')
self.newspace_dimension = dims[str(self.weight)]['new_dim']
except TypeError:
self.newspace_dimension = 'not available'
self.newspace_label = "-".join([self.field_label, self.level_label])
self.newspace_url = url_for(".render_bmf_space_webpage",
field_label=self.field_label,
level_label=self.level_label)
K = self.field.K()
if self.dimension > 1:
Qx = PolynomialRing(QQ, 'x')
self.hecke_poly = Qx(str(self.hecke_poly))
F = NumberField(self.hecke_poly, 'z')
self.hecke_poly = web_latex(self.hecke_poly)
def conv(ap):
if '?' in ap:
return 'not known'
else:
return F(str(ap))
self.hecke_eigs = [conv(str(ap)) for ap in self.hecke_eigs]
self.nap = len(self.hecke_eigs)
self.nap0 = min(50, self.nap)
self.hecke_table = [[
web_latex(p.norm()),
ideal_label(p),
web_latex(p.gens_reduced()[0]),
web_latex(ap)
] for p, ap in zip(primes_iter(K), self.hecke_eigs[:self.nap0])]
level = ideal_from_label(K, self.level_label)
self.level_ideal2 = web_latex(level)
badp = level.prime_factors()
self.have_AL = self.AL_eigs[0] != '?'
if self.have_AL:
self.AL_table = [[
web_latex(p.norm()),
ideal_label(p),
web_latex(p.gens_reduced()[0]),
web_latex(ap)
] for p, ap in zip(badp, self.AL_eigs)]
self.sign = 'not determined'
if self.sfe == 1:
self.sign = "+1"
elif self.sfe == -1:
self.sign = "-1"
if self.Lratio == '?':
self.Lratio = "not determined"
self.anrank = "not determined"
else:
self.Lratio = QQ(self.Lratio)
self.anrank = "\(0\)" if self.Lratio != 0 else "odd" if self.sfe == -1 else "\(\ge2\), even"
self.properties2 = [('Base field', pretty_field),
('Weight', str(self.weight)),
('Level norm', str(self.level_norm)),
('Level', self.level_ideal2),
('Label', self.label),
('Dimension', str(self.dimension))]
if self.CM == '?':
self.CM = 'not determined'
elif self.CM == 0:
self.CM = 'no'
self.properties2.append(('CM', str(self.CM)))
self.bc_extra = ''
self.bcd = 0
self.bct = self.bc != '?' and self.bc != 0
if self.bc == '?':
self.bc = 'not determined'
elif self.bc == 0:
self.bc = 'no'
elif self.bc == 1:
self.bcd = self.bc
self.bc = 'yes'
elif self.bc > 1:
self.bcd = self.bc
self.bc = 'yes'
self.bc_extra = ', of a form over \(\mathbb{Q}\) with coefficients in \(\mathbb{Q}(\sqrt{' + str(
self.bcd) + '})\)'
elif self.bc == -1:
self.bc = 'no'
self.bc_extra = ', but is a twist of the base-change of a form over \(\mathbb{Q}\)'
elif self.bc < -1:
self.bcd = -self.bc
self.bc = 'no'
self.bc_extra = ', but is a twist of the base-change of a form over \(\mathbb{Q}\) with coefficients in \(\mathbb{Q}(\sqrt{' + str(
self.bcd) + '})\)'
self.properties2.append(('Base-change', str(self.bc)))
curve_bc = db.ec_nfcurves.lucky({'class_label': self.label},
projection="base_change")
if curve_bc is not None:
self.ec_status = 'exists'
self.ec_url = url_for("ecnf.show_ecnf_isoclass",
nf=self.field_label,
conductor_label=self.level_label,
class_label=self.label_suffix)
curve_bc_parts = [split_lmfdb_label(lab) for lab in curve_bc]
bc_urls = [
url_for("emf.render_elliptic_modular_forms",
level=cond,
weight=2,
character=1,
label=iso) for cond, iso, num in curve_bc_parts
]
bc_labels = [
newform_label(cond, 2, 1, iso)
for cond, iso, num in curve_bc_parts
]
bc_exists = [is_newform_in_db(lab) for lab in bc_labels]
self.bc_forms = [{
'exists': ex,
'label': lab,
'url': url
} for ex, lab, url in zip(bc_exists, bc_labels, bc_urls)]
else:
self.bc_forms = []
if self.bct:
self.ec_status = 'none'
else:
self.ec_status = 'missing'
self.properties2.append(('Sign', self.sign))
self.properties2.append(('Analytic rank', self.anrank))
self.friends = []
if self.dimension == 1:
if self.ec_status == 'exists':
self.friends += [
('Elliptic curve isogeny class {}'.format(self.label),
self.ec_url)
]
elif self.ec_status == 'missing':
self.friends += [
('Elliptic curve {} missing'.format(self.label), "")
]
else:
self.friends += [('No elliptic curve', "")]
self.friends += [('Newspace {}'.format(self.newspace_label),
self.newspace_url)]
self.friends += [('L-function not available', '')]
class WebBMF(object):
"""
Class for a Bianchi Newform
"""
def __init__(self, dbdata, max_eigs=50):
"""Arguments:
- dbdata: the data from the database
dbdata is expected to be a database entry from which the class
is initialised.
"""
logger.debug("Constructing an instance of WebBMF class from database")
self.__dict__.update(dbdata)
# All other fields are handled here
self.make_form(max_eigs)
@staticmethod
def by_label(label, max_eigs=50):
"""
Searches for a specific Bianchi newform in the forms
collection by its label.
"""
data = db.bmf_forms.lookup(label)
if data:
return WebBMF(data, max_eigs)
raise ValueError("Bianchi newform %s not found" % label)
# caller must catch this and raise an error
def make_form(self, nap0=50):
# To start with the data fields of self are just those from
# the database. We need to reformat these and compute some
# further (easy) data about it.
#
from lmfdb.ecnf.WebEllipticCurve import FIELD
self.field = FIELD(self.field_label)
pretty_field = field_pretty(self.field_label)
self.field_knowl = nf_display_knowl(self.field_label, pretty_field)
try:
dims = db.bmf_dims.lucky(
{
'field_label': self.field_label,
'level_label': self.level_label
},
projection='gl2_dims')
self.newspace_dimension = dims[str(self.weight)]['new_dim']
except TypeError:
self.newspace_dimension = 'not available'
self.newspace_label = "-".join([self.field_label, self.level_label])
self.newspace_url = url_for(".render_bmf_space_webpage",
field_label=self.field_label,
level_label=self.level_label)
K = self.field.K()
# 'hecke_poly_obj' is the non-LaTeX version of hecke_poly
self.hecke_poly_obj = self.hecke_poly
if self.dimension > 1:
Qx = PolynomialRing(QQ, 'x')
self.hecke_poly = Qx(str(self.hecke_poly))
F = NumberField(self.hecke_poly, 'z')
self.hecke_poly = web_latex(self.hecke_poly)
def conv(ap):
if '?' in ap:
return 'not known'
else:
return F(str(ap))
self.hecke_eigs = [conv(str(ap)) for ap in self.hecke_eigs]
self.level = ideal_from_label(K, self.level_label)
self.level_ideal2 = web_latex(self.level)
badp = self.level.prime_factors()
self.nap = len(self.hecke_eigs)
self.nap0 = min(nap0, self.nap)
self.neigs = self.nap0 + len(badp)
self.hecke_table = [[
web_latex(p.norm()),
ideal_label(p),
web_latex(p.gens_reduced()[0]),
web_latex(ap)
] for p, ap in zip(primes_iter(K), self.hecke_eigs[:self.neigs])
if not p in badp]
self.have_AL = self.AL_eigs[0] != '?'
if self.have_AL:
self.AL_table = [[
web_latex(p.norm()),
ideal_label(p),
web_latex(p.gens_reduced()[0]),
web_latex(ap)
] for p, ap in zip(badp, self.AL_eigs)]
# The following helps to create Sage download data
self.AL_table_data = [[p.gens_reduced(), ap]
for p, ap in zip(badp, self.AL_eigs)]
self.sign = 'not determined'
try:
if self.sfe == 1:
self.sign = "$+1$"
elif self.sfe == -1:
self.sign = "$-1$"
except AttributeError:
self.sfe = '?'
if self.Lratio == '?':
self.Lratio = "not determined"
self.anrank = "not determined"
else:
self.Lratio = QQ(self.Lratio)
self.anrank = r"\(0\)" if self.Lratio != 0 else "odd" if self.sfe == -1 else r"\(\ge2\), even"
self.properties = [('Label', self.label), ('Base field', pretty_field),
('Weight', prop_int_pretty(self.weight)),
('Level norm', prop_int_pretty(self.level_norm)),
('Level', self.level_ideal2),
('Dimension', prop_int_pretty(self.dimension))]
try:
if self.CM == '?':
self.CM = 'not determined'
elif self.CM == 0:
self.CM = 'no'
else:
if int(self.CM) % 4 in [2, 3]:
self.CM = 4 * int(self.CM)
self.CM = "$%s$" % self.CM
except AttributeError:
self.CM = 'not determined'
self.properties.append(('CM', str(self.CM)))
self.bc_extra = ''
self.bcd = 0
self.bct = self.bc != '?' and self.bc != 0
if self.bc == '?':
self.bc = 'not determined'
elif self.bc == 0:
self.bc = 'no'
elif self.bc == 1:
self.bcd = self.bc
self.bc = 'yes'
elif self.bc > 1:
self.bcd = self.bc
self.bc = 'yes'
self.bc_extra = r', of a form over \(\mathbb{Q}\) with coefficients in \(\mathbb{Q}(\sqrt{' + str(
self.bcd) + r'})\)'
elif self.bc == -1:
self.bc = 'no'
self.bc_extra = r', but is a twist of the base change of a form over \(\mathbb{Q}\)'
elif self.bc < -1:
self.bcd = -self.bc
self.bc = 'no'
self.bc_extra = r', but is a twist of the base change of a form over \(\mathbb{Q}\) with coefficients in \(\mathbb{Q}(\sqrt{' + str(
self.bcd) + r'})\)'
self.properties.append(('Base change', str(self.bc)))
curve_bc = db.ec_nfcurves.lucky({'class_label': self.label},
projection="base_change")
if curve_bc is not None:
if curve_bc and "." not in curve_bc[0]:
curve_bc = [
cremona_label_to_lmfdb_label(lab) for lab in curve_bc
]
self.ec_status = 'exists'
self.ec_url = url_for("ecnf.show_ecnf_isoclass",
nf=self.field_label,
conductor_label=self.level_label,
class_label=self.label_suffix)
curve_bc_parts = [split_lmfdb_label(lab) for lab in curve_bc]
bc_urls = [
url_for("cmf.by_url_newform_label",
level=cond,
weight=2,
char_orbit_label='a',
hecke_orbit=iso) for cond, iso, num in curve_bc_parts
]
bc_labels = [
".".join([str(cond), str(2), 'a', iso])
for cond, iso, _ in curve_bc_parts
]
bc_exists = [db.mf_newforms.label_exists(lab) for lab in bc_labels]
self.bc_forms = [{
'exists': ex,
'label': lab,
'url': url
} for ex, lab, url in zip(bc_exists, bc_labels, bc_urls)]
else:
self.bc_forms = []
if self.bct or self.label in bmfs_with_no_curve:
self.ec_status = 'none'
else:
self.ec_status = 'missing'
self.properties.append(('Sign', self.sign))
self.properties.append(('Analytic rank', self.anrank))
self.friends = []
self.friends += [('Newspace {}'.format(self.newspace_label),
self.newspace_url)]
url = 'ModularForm/GL2/ImaginaryQuadratic/{}'.format(
self.label.replace('-', '/'))
Lfun = get_lfunction_by_url(url)
if Lfun:
instances = get_instances_by_Lhash_and_trace_hash(
Lfun['Lhash'], Lfun['degree'], Lfun['trace_hash'])
# This will also add the EC/G2C, as this how the Lfun was computed
# and not add itself
self.friends = names_and_urls(instances, exclude={url})
self.friends.append(('L-function', '/L/' + url))
else:
# old code
if self.dimension == 1:
if self.ec_status == 'exists':
self.friends += [('Isogeny class {}'.format(self.label),
self.ec_url)]
elif self.ec_status == 'missing':
self.friends += [
('Isogeny class {} missing'.format(self.label), "")
]
else:
self.friends += [('No elliptic curve', "")]
self.friends += [('L-function not available', '')]