def T(self, n):
"""
Return matrix mod 2 of the n-th Hecke operator on the +1
quotient of cuspidal modular symbols.
INPUT:
- `n` -- integer
OUTPUT:
matrix modulo 2
EXAMPLES::
sage: from mdsage import *
sage: C = KamiennyCriterion(29)
sage: C.T(2)
22 x 22 dense matrix over Finite Field of size 2 (use the '.str()' method to see the entries)
sage: C.T(2)[0]
(1, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 1, 0, 0, 1, 1)
"""
if self.verbose: tm = cputime(); mem = get_memory_usage(); print("T(%s) start" % (n))
T = self.M.hecke_matrix(n).restrict(self.S_integral, check=False)
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "T created")
if self.verbose: print("sparsity", len(T.nonzero_positions()) / RR(T.nrows()**2), T.nrows())
T = matrix_modp(T)
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "T reduced")
#self.M._hecke_matrices={}
#self.S._hecke_matrices={}
#if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "T freed"
return matrix_modp(T)
def verify_gamma1(self,d,t,v):
dependencies=[]
if self.verbose: tm = cputime(); mem = get_memory_usage(); print "verif gamma1 start"
satisfied=True
message=""
for i in xrange(d, (d - 1) // 2, -1):
#We only need to start at d/2 since the dependencies(k,l) contains all neccesary
#checks for largest partition of zise at most k and second largest at most l
dependency = self.dependencies(t, i, d - i, v)
dependencies.append(dependency)
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "dep (%s,%s)" % (i, d - i)
assert dependency.degree() == len(self.coset_representatives_H()) * (d - i) + 2 * i - d
assert dependency.degree() - dependency.dimension() <= self.S.dimension()
if dependency.dimension() == 0:
if self.verbose: print "...no dependencies found"
elif dependency.dimension() > 12:
satisfied=False
print "dependency dimension to large to search through"
else:
if self.verbose: print "dependency dimension is:", dependency.dimension()
min_dist = LinearCode(dependency).minimum_distance()
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "min dist"
if self.verbose: print "...the smallest dependency has %s nonzero coefficients." % (min_dist)
if min_dist > d:
if self.verbose: print i, d - i, "passed"
else:
satisfied,message= False, "There is a dependency of weigt %s in dependencies(%s,%s)" % (min_dist, i, d - i)
return satisfied, message,dependencies
def render_curve_webpage_by_label(label):
cpt0 = cputime()
t0 = time.time()
data = WebEC.by_label(label)
if data == "Invalid label":
return elliptic_curve_jump_error(label, {})
if data == "Curve not found":
return elliptic_curve_jump_error(label, {}, missing_curve=True)
try:
lmfdb_label = data.lmfdb_label
except AttributeError:
return elliptic_curve_jump_error(label, {})
data.modform_display = url_for(".modular_form_display", label=lmfdb_label, number="")
code = data.code()
code['show'] = {'magma':'','pari':'','sage':''} # use default show names
T = render_template("ec-curve.html",
properties=data.properties,
credit=ec_credit(),
data=data,
# set default show names but actually code snippets are filled in only when needed
code=code,
bread=data.bread, title=data.title,
friends=data.friends,
downloads=data.downloads,
KNOWL_ID="ec.q.%s"%lmfdb_label,
BACKUP_KNOWL_ID="ec.q.%s"%data.lmfdb_iso,
learnmore=learnmore_list())
ec_logger.debug("Total walltime: %ss"%(time.time() - t0))
ec_logger.debug("Total cputime: %ss"%(cputime(cpt0)))
return T
def render_curve_webpage_by_label(label):
cpt0 = cputime()
t0 = time.time()
data = WebEC.by_label(label)
if data == "Invalid label":
return elliptic_curve_jump_error(label, {}, wellformed_label=False)
if data == "Curve not found":
return elliptic_curve_jump_error(label, {}, wellformed_label=True, missing_curve=True)
try:
lmfdb_label = data.lmfdb_label
except AttributeError:
return elliptic_curve_jump_error(label, {}, wellformed_label=False)
data.modform_display = url_for(".modular_form_display", label=lmfdb_label, number="")
code = data.code()
code['show'] = {'magma':'','pari':'','sage':''} # use default show names
T = render_template("ec-curve.html",
properties2=data.properties,
credit=ec_credit(),
data=data,
# set default show names but actually code snippets are filled in only when needed
code=code,
bread=data.bread, title=data.title,
friends=data.friends,
downloads=data.downloads,
KNOWL_ID="ec.q.%s"%label,
BACKUP_KNOWL_ID="ec.q.%s"%data.lmfdb_iso,
learnmore=learnmore_list())
ec_logger.debug("Total walltime: %ss"%(time.time() - t0))
ec_logger.debug("Total cputime: %ss"%(cputime(cpt0)))
return T
def compute_ambient_space(N, k, i):
if i == 'all':
G = DirichletGroup(N).galois_orbits()
sgn = (-1)**k
for j, g in enumerate(G):
if g[0](-1) == sgn:
compute_ambient_space(N,k,j)
return
if i == 'quadratic':
G = DirichletGroup(N).galois_orbits()
sgn = (-1)**k
for j, g in enumerate(G):
if g[0](-1) == sgn and g[0].order()==2:
compute_ambient_space(N,k,j)
return
filename = filenames.ambient(N, k, i)
if os.path.exists(filename):
return
eps = character(N, i)
t = cputime()
M = ModularSymbols(eps, weight=k, sign=1)
tm = cputime(t)
save(M, filename)
meta = {'cputime':tm, 'dim':M.dimension(), 'M':str(M), 'version':version()}
save(meta, filenames.meta(filename))
def T(self, n):
"""
Return matrix mod 2 of the n-th Hecke operator on the +1
quotient of cuspidal modular symbols.
INPUT:
- `n` -- integer
OUTPUT:
matrix modulo 2
EXAMPLES::
sage: from mdsage import *
sage: C = KamiennyCriterion(29)
sage: C.T(2)
22 x 22 dense matrix over Finite Field of size 2 (use the '.str()' method to see the entries)
sage: C.T(2)[0]
(1, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 1, 0, 0, 1, 1)
"""
if self.verbose: tm = cputime(); mem = get_memory_usage(); print "T(%s) start" % (n)
T = self.M.hecke_matrix(n).restrict(self.S_integral, check=False)
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "T created"
if self.verbose: print "sparsity", len(T.nonzero_positions()) / RR(T.nrows()**2), T.nrows()
T = matrix_modp(T)
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "T reduced"
#self.M._hecke_matrices={}
#self.S._hecke_matrices={}
#if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "T freed"
return matrix_modp(T)
def compute_atkin_lehner(N, k, i):
filename = filenames.ambient(N, k, i)
if not os.path.exists(filename):
print "Ambient (%s,%s,%s) space not computed."%(N,k,i)
return
#compute_ambient_space(N, k, i)
print "computing atkin-lehner for (%s,%s,%s)"%(N,k,i)
m = filenames.number_of_known_factors(N, k, i)
M = load_ambient_space(N, k, i)
for d in range(m):
atkin_lehner_file = filenames.factor_atkin_lehner(N, k, i, d, False)
if os.path.exists(atkin_lehner_file):
print "skipping computing atkin_lehner for (%s,%s,%s,%s) since it already exists"%(N,k,i,d)
# already done
continue
# compute atkin_lehner
print "computing atkin_lehner for (%s,%s,%s,%s)"%(N,k,i,d)
t = cputime()
A = load_factor(N, k, i, d, M)
al = ' '.join(['+' if a > 0 else '-' for a in atkin_lehner_signs(A)])
print al
open(atkin_lehner_file, 'w').write(al)
tm = cputime(t)
meta = {'cputime':tm, 'version':version()}
save(meta, filenames.meta(atkin_lehner_file))
def verify_gamma1(self,d,t,v):
dependencies=[]
if self.verbose: tm = cputime(); mem = get_memory_usage(); print("verif gamma1 start")
satisfied=True
message=""
for i in range(d, (d - 1) // 2, -1):
#We only need to start at d/2 since the dependencies(k,l) contains all neccesary
#checks for largest partition of zise at most k and second largest at most l
dependency = self.dependencies(t, i, d - i, v)
dependencies.append(dependency)
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "dep (%s,%s)" % (i, d - i))
assert dependency.degree() == len(self.coset_representatives_H()) * (d - i) + 2 * i - d
assert dependency.degree() - dependency.dimension() <= self.S.dimension()
if dependency.dimension() == 0:
if self.verbose: print("...no dependencies found")
elif dependency.dimension() > 12:
satisfied=False
print("dependency dimension to large to search through")
else:
if self.verbose: print("dependency dimension is:", dependency.dimension())
min_dist = LinearCode(dependency).minimum_distance()
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "min dist")
if self.verbose: print("...the smallest dependency has %s nonzero coefficients." % (min_dist))
if min_dist > d:
if self.verbose: print(i, d - i, "passed")
else:
satisfied,message= False, "There is a dependency of weigt %s in dependencies(%s,%s)" % (min_dist, i, d - i)
return satisfied, message,dependencies
def g(N):
from sage.misc.misc import alarm, cancel_alarm
alarm(maxtime)
from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker
engine = create_engine('postgresql://[email protected]:6432/mrc2', echo=False)
s = sessionmaker(bind=engine)()
t = cputime()
x,y,z = ideal_to_tuple(N)
q = s.query(Space).filter(Space.x==x).filter(Space.y==y).filter(Space.z==z)
if q.count() > 0:
M = q.one()
if M.number_of_rational_newforms == len(M.rational_newforms):
return "Already done with level %s (norm = %s)"%(N, N.norm())
H = M.hmf()
else:
H = QuaternionicModule(N)
M = store_space(s, H)
V, rational_oldform_dimension = H.dual_rational_newforms(verb=verb)
for vdual, aplist in V:
f = RationalNewform()
for p, ap in aplist:
f.store_eigenvalue(p, ap)
M.rational_newforms.append(f)
f.dual_vector = ns_str(canonically_scale(vdual))
M.number_of_rational_newforms = len(V)
M.rational_oldform_dimension = int(rational_oldform_dimension)
M.time_to_compute_newforms = cputime(t)
s.commit()
cancel_alarm()
return N.norm(), cputime(t), len(V)
def compute_aplists(N, k, i, *args):
if i == 'all':
G = DirichletGroup(N).galois_orbits()
sgn = (-1)**k
for j, g in enumerate(G):
if g[0](-1) == sgn:
compute_aplists(N,k,j,*args)
return
if i == 'quadratic':
G = DirichletGroup(N).galois_orbits()
sgn = (-1)**k
for j, g in enumerate(G):
if g[0](-1) == sgn and g[0].order()==2:
compute_aplists(N,k,j,*args)
return
if len(args) == 0:
args = (100, )
filename = filenames.ambient(N, k, i)
if not os.path.exists(filename):
print "Ambient (%s,%s,%s) space not computed."%(N,k,i)
return
#compute_ambient_space(N, k, i)
print "computing aplists for (%s,%s,%s)"%(N,k,i)
m = filenames.number_of_known_factors(N, k, i)
if m == 0:
# nothing to do
return
M = load_ambient_space(N, k, i)
for d in range(m):
aplist_file = filenames.factor_aplist(N, k, i, d, False, *args)
if os.path.exists(aplist_file):
print "skipping computing aplist(%s) for (%s,%s,%s,%s) since it already exists"%(args, N,k,i,d)
# already done
continue
# compute aplist
print "computing aplist(%s) for (%s,%s,%s,%s)"%(args, N,k,i,d)
t = cputime()
A = load_factor(N, k, i, d, M)
aplist, _ = A.compact_system_of_eigenvalues(prime_range(*args), 'a')
print aplist, aplist_file
save(aplist, aplist_file)
tm = cputime(t)
meta = {'cputime':tm, 'version':version()}
save(meta, filenames.meta(aplist_file))
def compute_decompositions(N, k, i):
if i == 'all':
G = DirichletGroup(N).galois_orbits()
sgn = (-1)**k
for j, g in enumerate(G):
if g[0](-1) == sgn:
compute_decompositions(N,k,j)
return
if i == 'quadratic':
G = DirichletGroup(N).galois_orbits()
sgn = (-1)**k
for j, g in enumerate(G):
if g[0](-1) == sgn and g[0].order()==2:
compute_decompositions(N,k,j)
return
filename = filenames.ambient(N, k, i)
if not os.path.exists(filename):
print "Ambient space (%s,%s,%s) not computed."%(N,k,i)
return
#compute_ambient_space(N, k, i)
if not os.path.exists(filename):
return
eps = DirichletGroup(N).galois_orbits()[i][0]
if os.path.exists(filenames.factor(N, k, i, 0, makedir=False)):
return
t = cputime()
M = load_ambient_space(N, k, i)
D = M.cuspidal_subspace().new_subspace().decomposition()
for d in range(len(D)):
f = filenames.factor_basis_matrix(N, k, i, d)
if os.path.exists(f):
continue
A = D[d]
B = A.free_module().basis_matrix()
Bd = A.dual_free_module().basis_matrix()
v = A.dual_eigenvector(names='a', lift=False) # vector over number field
nz = A._eigen_nonzero()
save(B, filenames.factor_basis_matrix(N, k, i, d))
save(Bd, filenames.factor_dual_basis_matrix(N, k, i, d))
save(v, filenames.factor_dual_eigenvector(N, k, i, d))
save(nz, filenames.factor_eigen_nonzero(N, k, i, d))
tm = cputime(t)
meta = {'cputime':tm, 'number':len(D), 'version':version()}
save(meta, filenames.decomp_meta(N, k, i))
def process_curve_batch(folder, batch, digits=600, power=15):
# cursor = list(C.genus2_curves.curves.find({'is_simple_geom': true,'real_geom_end_alg': u'R x R'}).sort([("cond", ASCENDING)]))
totalcurves = len(batch)
D = {}
success = 0
total = 0
failed = []
for i, curve in enumerate(batch):
label = curve['label']
stdout_filename = os.path.join(folder, label + ".stdout")
output_filename = os.path.join(folder, label + ".sage")
print "%d of %d : label = %s" % (i + 1, totalcurves, label)
sys.stdout = open(stdout_filename, 'w')
c, w = cputime(), walltime()
data, sout = process_curve_lmfdb(curve,
digits,
power=power,
verbose=True,
internalverbose=False)
print "Time: CPU %.2f s, Wall: %.2f s" % (
cputime(c),
walltime(w),
)
output_file = open(output_filename, 'w')
output_file.write(sout)
output_file.close()
D[label] = True
sys.stdout.flush()
os.fsync(sys.stdout.fileno())
sys.stdout = sys.__stdout__
total += 1
if label in D.keys():
success += 1
print "Done: label = %s" % (label)
print os.popen("tail -n 1 %s" % stdout_filename).read()
else:
failed += [label]
print "ERROR: label = %s\n" % (label)
print "Success rate: %.0f%%\n" % (100. * success / total)
print "Failed so far %s" % failed
def ambient_integral_structure_matrix(M,verbose=False):
"""
In certatain cases (weight two any level) this might return the integral structure of a
an ambient modular symbol space. I wrote this because for high level this is very slow
in sage because there is no good sparse hermite normal form code in sage for huge matrices.
"""
if verbose: tm = cputime(); mem = get_memory_usage(); print "Int struct start"
#This code is the same as the firs part of M.integral_structure
G = set([i for i, _ in M._mod2term])
G = list(G)
G.sort()
#if there is a two term relation between two manin symbols we only need one of the two
#so that's why we only use elements from G instead of all manin symbols.
if verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "G"
B = M._manin_gens_to_basis.matrix_from_rows(list(G)).sparse_matrix()
if verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "B"
#The collums of B now span M.integral_structure as ZZ-module
B, d = B._clear_denom()
if verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "Clear denom"
if d == 1:
#for explanation see d == 2
assert len(set([B.nonzero_positions_in_row(i)[0] for i in xrange(B.nrows()) if len(B.nonzero_positions_in_row(i)) == 1 and B[i, B.nonzero_positions_in_row(i)[0]] == 1])) == B.ncols(), "B doesn't contain the Identity"
if verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "Check Id"
ZZbasis = MatrixSpace(QQ, B.ncols(), sparse=True)(1)
if verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "ZZbasis"
elif d == 2:
#in this case the matrix B will contain 2*Id as a minor this allows us to compute the hermite normal form of B in a very efficient way. This will give us the integral basis ZZbasis.
#if it turns out to be nessecarry this can be generalized to the case d%4==2 if we don't mind to only get the right structure localized at 2
assert len(set([B.nonzero_positions_in_row(i)[0] for i in xrange(B.nrows()) if len(B.nonzero_positions_in_row(i)) == 1 and B[i, B.nonzero_positions_in_row(i)[0]] == 2])) == B.ncols(), "B doesn't contain 2*Identity"
if verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "Check 2*Id"
E = matrix_modp(B,sparse=True)
if verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "matmodp"
E = E.echelon_form()
if verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "echelon"
ZZbasis = MatrixSpace(QQ, B.ncols(), sparse=True)(1)
for (pivot_row, pivot_col) in zip(E.pivot_rows(), E.pivots()):
for j in E.nonzero_positions_in_row(pivot_row):
ZZbasis[pivot_col, j] = QQ(1) / 2
if verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "ZZbasis"
else:
raise NotImplementedError
return ZZbasis
def ambient_integral_structure_matrix(M,verbose=False):
"""
In certatain cases (weight two any level) this might return the integral structure of a
an ambient modular symbol space. I wrote this because for high level this is very slow
in sage because there is no good sparse hermite normal form code in sage for huge matrices.
"""
if verbose: tm = cputime(); mem = get_memory_usage(); print("Int struct start")
#This code is the same as the firs part of M.integral_structure
G = set([i for i, _ in M._mod2term])
G = list(G)
G.sort()
#if there is a two term relation between two manin symbols we only need one of the two
#so that's why we only use elements from G instead of all manin symbols.
if verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "G")
B = M._manin_gens_to_basis.matrix_from_rows(list(G)).sparse_matrix()
if verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "B")
#The collums of B now span M.integral_structure as ZZ-module
B, d = B._clear_denom()
if verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "Clear denom")
if d == 1:
#for explanation see d == 2
assert len(set([B.nonzero_positions_in_row(i)[0] for i in range(B.nrows()) if len(B.nonzero_positions_in_row(i)) == 1 and B[i, B.nonzero_positions_in_row(i)[0]] == 1])) == B.ncols(), "B doesn't contain the Identity"
if verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "Check Id")
ZZbasis = MatrixSpace(QQ, B.ncols(), sparse=True)(1)
if verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "ZZbasis")
elif d == 2:
#in this case the matrix B will contain 2*Id as a minor this allows us to compute the hermite normal form of B in a very efficient way. This will give us the integral basis ZZbasis.
#if it turns out to be nessecarry this can be generalized to the case d%4==2 if we don't mind to only get the right structure localized at 2
assert len(set([B.nonzero_positions_in_row(i)[0] for i in range(B.nrows()) if len(B.nonzero_positions_in_row(i)) == 1 and B[i, B.nonzero_positions_in_row(i)[0]] == 2])) == B.ncols(), "B doesn't contain 2*Identity"
if verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "Check 2*Id")
E = matrix_modp(B,sparse=True)
if verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "matmodp")
E = E.echelon_form()
if verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "echelon")
ZZbasis = MatrixSpace(QQ, B.ncols(), sparse=True)(1)
for (pivot_row, pivot_col) in zip(E.pivot_rows(), E.pivots()):
for j in E.nonzero_positions_in_row(pivot_row):
ZZbasis[pivot_col, j] = QQ(1) / 2
if verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "ZZbasis")
else:
raise NotImplementedError
return ZZbasis
def dbd(self, d):
"""
Return matrix of <d>.
INPUT:
- `d` -- integer
OUTPUT:
- a matrix modulo 2
EXAMPLES::
sage: from mdsage import *
sage: C = KamiennyCriterion(29)
sage: C.dbd(2)
22 x 22 dense matrix over Finite Field of size 2 (use the '.str()' method to see the entries)
sage: C.dbd(2)^14==1
True
sage: C.dbd(2)[0]
(0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0, 1, 1, 1)
"""
d=ZZ(d)
if self.verbose: tm = cputime(); mem = get_memory_usage(); print "dbd start"
try: return self._dbd[d % self.p]
except AttributeError: pass
# Find generators of the integers modulo p:
gens = Integers(self.p).unit_gens()
orders = [g.multiplicative_order() for g in gens]
# Compute corresponding <z> operator on integral cuspidal modular symbols
X = [self.M.diamond_bracket_operator(z).matrix() for z in gens]
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "create d"
X = [x.restrict(self.S_integral, check=False) for x in X]
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "restrict d"
X = [matrix_modp(x) for x in X]
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "mod d"
# Take combinations to make list self._dbd of all dbd's such that
# self._dbd[d] = <d>
from itertools import product
v = [None] * self.p
for ei in product(*[range(i) for i in orders]):
di = prod(g**e for e,g in zip(ei,gens)).lift()
m = prod(g**e for e,g in zip(ei,X))
v[di] = m
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "mul"
assert v.count(None) == (self.p-euler_phi(self.p))
self._dbd = v
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "bdb finnished"
return v[d % self.p]
def dbd(self, d):
"""
Return matrix of <d>.
INPUT:
- `d` -- integer
OUTPUT:
- a matrix modulo 2
EXAMPLES::
sage: from mdsage import *
sage: C = KamiennyCriterion(29)
sage: C.dbd(2)
22 x 22 dense matrix over Finite Field of size 2 (use the '.str()' method to see the entries)
sage: C.dbd(2)^14==1
True
sage: C.dbd(2)[0]
(0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0, 1, 1, 1)
"""
d=ZZ(d)
if self.verbose: tm = cputime(); mem = get_memory_usage(); print("dbd start")
try: return self._dbd[d % self.p]
except AttributeError: pass
# Find generators of the integers modulo p:
gens = Integers(self.p).unit_gens()
orders = [g.multiplicative_order() for g in gens]
# Compute corresponding <z> operator on integral cuspidal modular symbols
X = [self.M.diamond_bracket_operator(z).matrix() for z in gens]
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "create d")
X = [x.restrict(self.S_integral, check=False) for x in X]
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "restrict d")
X = [matrix_modp(x) for x in X]
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "mod d")
# Take combinations to make list self._dbd of all dbd's such that
# self._dbd[d] = <d>
from itertools import product
v = [None] * self.p
for ei in product(*[list(range(i)) for i in orders]):
di = prod(g**e for e,g in zip(ei,gens)).lift()
m = prod(g**e for e,g in zip(ei,X))
v[di] = m
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "mul")
assert v.count(None) == (self.p-euler_phi(self.p))
self._dbd = v
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "bdb finnished")
return v[d % self.p]
def cuspidal_integral_structure_matrix(M,verbose=False):
"""
Computes the cuspidal integral structure matrix of a modular symbols space in a runningtime hopefully faster then that of sage
Input:
- M - a modular symbols space
Output:
- a matrix whose rows give a ZZ basis for the cuspidals supspace with respect to the standard basis of M
Tests::
sage: from mdsage import *
sage: M = ModularSymbols(Gamma1(15))
sage: cuspidal_integral_structure_matrix(M)
[ 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 -1 0]
[ 0 0 0 0 0 1 0 0 1 0 0 -1 0 0 0 0 0]
"""
#now we compute the integral kernel of the boundary map with respect to the integral basis. This will give us the integral cuspidal submodule.
if verbose: tm = cputime(); mem = get_memory_usage();
ZZbasis = ambient_integral_structure_matrix(M,verbose=verbose)
boundary_matrix = M.boundary_map().matrix()
if verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "Boundary matrix"
ZZboundary_matrix=(ZZbasis*boundary_matrix).change_ring(ZZ)
if verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "ZZBoundary matrix"
left_kernel_matrix=ZZboundary_matrix.transpose().dense_matrix()._right_kernel_matrix(algorithm='pari')
if type(left_kernel_matrix)==tuple:
left_kernel_matrix=left_kernel_matrix[1]
if verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "kernel matrix"
ZZcuspidal_basis=left_kernel_matrix*ZZbasis
if verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "ZZkernel matrix"
S=M.cuspidal_subspace()
assert ZZcuspidal_basis.change_ring(QQ).echelon_form()==S.basis_matrix() , "the calculated integral basis does not span the right QQ vector space" # a little sanity check. This shows that the colums of ZZcuspidal_basis really span the right QQ vectorspace
if verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "finnished"
return ZZcuspidal_basis
def cuspidal_integral_structure_matrix(M,verbose=False):
"""
Computes the cuspidal integral structure matrix of a modular symbols space in a runningtime hopefully faster then that of sage
Input:
- M - a modular symbols space
Output:
- a matrix whose rows give a ZZ basis for the cuspidals supspace with respect to the standard basis of M
Tests::
sage: from mdsage import *
sage: M = ModularSymbols(Gamma1(15))
sage: cuspidal_integral_structure_matrix(M)
[ 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 -1 0]
[ 0 0 0 0 0 1 0 0 1 0 0 -1 0 0 0 0 0]
"""
#now we compute the integral kernel of the boundary map with respect to the integral basis. This will give us the integral cuspidal submodule.
if verbose: tm = cputime(); mem = get_memory_usage();
ZZbasis = ambient_integral_structure_matrix(M,verbose=verbose)
boundary_matrix = M.boundary_map().matrix()
if verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "Boundary matrix")
ZZboundary_matrix=(ZZbasis*boundary_matrix).change_ring(ZZ)
if verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "ZZBoundary matrix")
left_kernel_matrix=ZZboundary_matrix.transpose().dense_matrix()._right_kernel_matrix(algorithm='pari')
if type(left_kernel_matrix)==tuple:
left_kernel_matrix=left_kernel_matrix[1]
if verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "kernel matrix")
ZZcuspidal_basis=left_kernel_matrix*ZZbasis
if verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "ZZkernel matrix")
S=M.cuspidal_subspace()
assert ZZcuspidal_basis.change_ring(QQ).echelon_form()==S.basis_matrix() , "the calculated integral basis does not span the right QQ vector space" # a little sanity check. This shows that the colums of ZZcuspidal_basis really span the right QQ vectorspace
if verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "finnished")
return ZZcuspidal_basis
def certify_heuristic(g,
label=None,
digits=600,
power=15,
verbose=True,
internalverbose=False):
from heuristic_endomorphisms import EndomorphismData
out = ""
curve_dict = {}
curve_dict['label'] = label
curve_dict['digits'] = digits
prec = ceil(log(10) / log(2) * digits)
curve_dict['prec'] = prec
buffer = "curve_dict = {};\n"
for key in ['digits', 'prec']:
buffer += "curve_dict['%s'] = %s;\n" % (key, curve_dict[key])
buffer += "curve_dict['%s'] = '%s';\n" % ('label', label)
if verbose:
print buffer
out += buffer
#Ambient ring
buffer = ""
buffer += "\n# basic rings\n"
buffer += "curve_dict['%s'] = %s;\n" % ('QQx', 'PolynomialRing(QQ, \'x\')')
buffer += "# curve_dict, x, and the number field's generator are the only variables are the only global variables\n\n"
buffer += "x = curve_dict['QQx'].gen();\n\n"
out += buffer
Qx = PolynomialRing(QQ, "x")
x = Qx.gen()
curve_dict['QQx'] = Qx
# force g in Qx
g = Qx(g.list())
# Compute EndomorphismData
# field of definition
# and endomorphisms
xsubs_list = [x, x + 1, x - 1, 1 - x, -1 - x, x + 2, x - 2, -x - 2, 2 - x]
if label == '540800.a.540800.1':
xsubs_list = xsubs_list[1:]
for xsubs in xsubs_list:
try:
gtry = g(xsubs)
if gtry.degree() == 5:
gtry = Qx(gtry(x**(-1)) * x**6)
if gtry.degree() == 5:
gtry = Qx(gtry((x - 1) / x) * x**6)
if verbose:
print "Computing the EndomorphismData..."
c, w = cputime(), walltime()
End = EndomorphismData(gtry, prec=digits)
print "Time: CPU %.2f s, Wall: %.2f s" % (
cputime(c),
walltime(w),
)
else:
End = EndomorphismData(gtry, prec=digits)
geo = End.geometric_representations()
K = End.field_of_definition()
g = gtry
break
except TypeError:
pass
if label == '810.a.196830.1':
power += 2
buffer = "#working with the model y^2 = g(x)\n"
buffer += "curve_dict['%s'] = %s;\n" % ('g', g.list())
curve_dict['g'] = g.list()
out += buffer
if verbose:
print buffer
# initialize numerical methods
iaj = InvertAJglobal(g, prec, internalverbose)
#CCap = iaj.C;
buffer += "curve_dict['%s'] = %s;\n" % ('CCap', ' ComplexField(%s)' %
curve_dict['prec'])
#buffer += "CCap = curve_dict['CCap'];\n\n"
# generator is r
K = End.field_of_definition()
if K.degree() == 1:
K = QQ
buffer = "# Field of definition of alpha\n"
buffer += "curve_dict['%s'] = %s;\n" % ('K',
sage_str_numberfield(K, 'x', 'r'))
buffer += "K = %s\n" % ("curve_dict['K']")
if K is not QQ:
buffer += "r_approx = %s\n" % (K.gen().complex_embedding(), )
out += buffer
out += "r = K.gen();\n"
if verbose:
print buffer
#get the matrices over K
geo = End.geometric_representations()
#convert to sage
# we also must take the transpose
alphas = [convert_magma_matrix_to_sage(y, K).transpose() for y in geo[0]]
alphas_geo = [y.sage() for y in geo[2]]
d = len(alphas)
out += "curve_dict['alphas_K'] = [None] * %d\n\n" % d
out += "curve_dict['alphas_geo'] = [None] * %d\n\n" % d
for i, _ in enumerate(alphas):
alpha = alphas[i]
alpha_geo = alphas_geo[i]
buffer = "curve_dict['alphas_K'][%d] = Matrix(K, %s);\n" % (
i,
alpha.rows(),
)
buffer += "curve_dict['alphas_geo'][%d] = Matrix(%s);\n\n" % (
i,
alpha_geo.rows(),
)
out += buffer
if verbose:
print buffer
curve_dict['alphas_K'] = alphas
curve_dict['alphas_geo'] = alphas_geo
out += "# where we stored all the data, for each alpha\n"
out += "curve_dict['data'] = [{} for _ in range(%d) ] ;" % d
curve_dict['data'] = [{} for _ in range(d)]
for i in range(d):
if alphas[i] == Matrix([[1, 0], [0, 1]]):
curve_dict['data'][i] = None
else:
if verbose:
print "Computing alpha(P + P)"
print "where alpha = Matrix(K, %s)\n" % (alphas[i].rows(), )
# Pick a rational point, or a point over a quadratic extension with small discriminant
for j, P0 in enumerate(find_rational_point(g)):
if label in [
'540800.a.540800.1', '529.a.529.1', '1521.a.41067.1',
'12500.a.12500.1', '18225.c.164025.1'
] and j < 2:
pass
elif label in ['810.a.196830.1'] and i == 2 and j == 0:
pass
else:
if verbose:
print "j = %s" % j
sys.stdout.flush()
sys.stderr.flush()
try:
output_alpha = compute_alpha_point(g,
iaj,
alphas[i],
P0,
digits,
power,
verbose=verbose,
aggressive=True,
append=str(i))
verified, trace_and_norm = add_trace_and_norm_ladic(
g, output_alpha, alphas_geo[i], verbose=verbose)
break
except ZeroDivisionError:
pass
except OverflowError:
if verbose:
print "the mesh for numerical integral is too big"
pass
if verbose:
print "trying with a new point\n"
if verbose:
print "\n\n\n"
output_alpha['trace_and_norm'] = trace_and_norm
output_alpha['verified'] = verified
output_alpha['alphas_geo'] = alphas_geo[i]
internal_out = "\n"
#local_dict = {}\n\n";
#
# the fields
internal_out += "# L the field where P and the algx_poly are defined\n"
internal_out += "curve_dict['data'][%d]['L'] = %s\n" % (
i,
sage_str_numberfield(output_alpha['L'], 'x', 'b' + str(i)),
)
if output_alpha['L'] is not QQ:
internal_out += "b%d = curve_dict['data'][%d]['L'].gen()\n" % (
i, i)
internal_out += "curve_dict['data'][%d]['Lgen_approx'] = %s\n" % (
i, output_alpha['L'].gen().complex_embedding())
internal_out += "\n"
internal_out += "curve_dict['data'][%d]['alpha'] = Matrix(curve_dict['data'][%d]['L'], %s) \n\n" % (
i, i, [[elt for elt in row]
for row in output_alpha['alpha'].rows()])
internal_out += "curve_dict['data'][%d]['alpha_geo'] = curve_dict['alphas_geo'][%d]\n\n" % (
i, i)
internal_out += "curve_dict['data'][%d]['P'] = vector(curve_dict['data'][%d]['L'], %s)\n\n" % (
i, i, output_alpha['P'])
internal_out += "# alpha(P + P) - \inf = R0 + R1 - \inf\n"
internal_out += "\n\n\n"
for key in [
'algx_poly', 'R', 'x_poly', 'trace_and_norm', 'verified'
]:
internal_out += "curve_dict['data'][%d]['%s'] = %s;\n" % (
i, key, output_alpha[key])
# this just clutters the file,
# internal_out += "curve_dict['data'][%d]['ajP'] = vector(%s)\n\n" % (i, output_alpha['ajP']);
# internal_out += "curve_dict['data'][%d]['alpha2P0'] = alphas_ap[%d] * 2 * local_dict['ajP']\n\n" % (i, i)
internal_out += "\n\n\n"
curve_dict['data'][i] = output_alpha
out += internal_out
verified = all(
[elt['verified'] for elt in curve_dict['data'] if elt is not None])
out += "curve_dict['verified'] = %s\n\n" % verified
return curve_dict, out, verified
def integral_cuspidal_subspace(self):
"""
In certatain cases this might return the integral structure of the cuspidal subspace.
This code is mainly a way to compute the integral structe faster than sage does now.
It returns None if it cannot find the integral subspace.
"""
if self.verbose: tm = cputime(); mem = get_memory_usage(); print("Int struct start")
#This code is the same as the firs part of self.M.integral_structure
G = set([i for i, _ in self.M._mod2term])
G = list(G)
G.sort()
#if there is a two term relation between two manin symbols we only need one of the two
#so that's why we only use elements from G instead of all manin symbols.
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "G")
B = self.M._manin_gens_to_basis.matrix_from_rows(list(G)).sparse_matrix()
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "B")
#The collums of B now span self.M.integral_structure as ZZ-module
B, d = B._clear_denom()
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "Clear denom")
if d == 1:
#for explanation see d == 2
assert len(set([B.nonzero_positions_in_row(i)[0] for i in range(B.nrows()) if len(B.nonzero_positions_in_row(i)) == 1 and B[i, B.nonzero_positions_in_row(i)[0]] == 1])) == B.ncols(), "B doesn't contain the Identity"
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "Check Id")
ZZbasis = MatrixSpace(QQ, B.ncols(), sparse=True)(1)
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "ZZbasis")
elif d == 2:
#in this case the matrix B will contain 2*Id as a minor this allows us to compute the hermite normal form of B in a very efficient way. This will give us the integral basis ZZbasis.
#if it turns out to be nessecarry this can be generalized to the case d%4==2 if we don't mind to only get the right structure localized at 2
assert len(set([B.nonzero_positions_in_row(i)[0] for i in range(B.nrows()) if len(B.nonzero_positions_in_row(i)) == 1 and B[i, B.nonzero_positions_in_row(i)[0]] == 2])) == B.ncols(), "B doesn't contain 2*Identity"
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "Check 2*Id")
E = matrix_modp(B,sparse=True)
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "matmodp")
E = E.echelon_form()
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "echelon")
ZZbasis = MatrixSpace(QQ, B.ncols(), sparse=True)(1)
for (pivot_row, pivot_col) in zip(E.pivot_rows(), E.pivots()):
for j in E.nonzero_positions_in_row(pivot_row):
ZZbasis[pivot_col, j] = QQ(1) / 2
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "ZZbasis")
else:
return None
#now we compute the integral kernel of the boundary map with respect to the integral basis. This will give us the integral cuspidal submodule.
boundary_matrix = self.M.boundary_map().matrix()
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "Boundary matrix")
ZZboundary_matrix=(ZZbasis*boundary_matrix).change_ring(ZZ)
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "ZZBoundary matrix")
left_kernel_matrix=ZZboundary_matrix.transpose().dense_matrix()._right_kernel_matrix(algorithm='pari')
if type(left_kernel_matrix)==tuple:
left_kernel_matrix=left_kernel_matrix[1]
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "kernel matrix")
ZZcuspidal_basis=left_kernel_matrix*ZZbasis
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "ZZkernel matrix")
assert ZZcuspidal_basis.change_ring(QQ).echelon_form()==self.S.basis_matrix() , "the calculated integral basis does not span the right QQ vector space" # a little sanity check. This shows that the colums of ZZcuspidal_basis really span the right QQ vectorspace
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "check")
#finally create the sub-module, we delibarately do this as a QQ vector space with custom basis, because this is faster then dooing the calculations over ZZ since sage will then use a slow hermite normal form algorithm.
ambient_module=VectorSpace(QQ,ZZcuspidal_basis.ncols())
int_struct = ambient_module.submodule_with_basis(ZZcuspidal_basis.rows())
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "finnished")
return int_struct
def compute_alpha_point(g,
iaj,
alpha,
P0,
digits,
power,
verbose,
aggressive=True,
append=""):
# input:
# * g, defining polynomial of the hyperelliptic curve
# * iaj = InvertAJglobal class
# * alpha = analytic representation of the endomorphism acting on the tangent space
# * digits = how many digits to work with
# * power, we will divide by 2**power before inverting the abel jacobi map
# * P0, a point in the curve for which we will compute alpha*2(P - \infty) = P1 + P2 - \infty
# * verbose
# * agressive, raise ZeroDivisionError if we get a P1[0] = P2[0] or one of the points is infty
# * append, a string to append to the numberfield generators
#
# output: a dictionary with the following keys
# TODO add the keys
output = {}
K = alpha.base_ring()
CCap = iaj.C
prec = CCap.precision()
output['prec'] = prec
x0, y0 = P0
Kz = PolynomialRing(K, "z")
z = Kz.gen()
if verbose:
print "compute_alpha_point()"
print "P0 = %s" % (P0, )
#deal with the field of definition
if y0 in K:
if K is QQ:
L = K
from_K_to_L = QQ.hom(1, QQ)
else:
L = K.change_names("b" + append)
from_K_to_L = L.structure()[1]
else:
L, from_K_to_L = (z**2 - g(x0)).splitting_field("b" + append,
simplify_all=True,
map=True)
output['L'] = L
# output['L_str'] = sage_str_numberfield(L, 'x','b'+append);
output['from_K_to_L'] = from_K_to_L
# output['L_gen'] = toCCap(L.gen(), 53);
# figure out y0 in L
y0_ap = toCCap(y0, prec)
y0s = [elt for elt, _ in (z**2 - g(x0)).roots(L)]
assert len(y0s) == 2
y0s_ap = [toCCap(elt, prec) for elt in y0s]
if norm(y0_ap - y0s_ap[0]) < norm(y0_ap - y0s_ap[1]):
y0 = y0s[0]
else:
y0 = y0s[1]
P0 = vector(L, [x0, y0])
alpha_L = Matrix(L, [[from_K_to_L(elt) for elt in row]
for row in alpha.rows()])
alpha_ap = Matrix(CCap, [toCCap_list(row, prec) for row in alpha_L.rows()])
output['P'] = P0
output['alpha'] = alpha_L
if verbose:
print "L = %s" % L
print "%s = %s" % (L.gen(), toCCap(L.gen(), 53))
print "P0 = %s" % (P0, )
print "alpha = %s" % ([[elt for elt in row]
for row in alpha_L.rows()], )
P0_ap = vector(CCap, toCCap_list(P0, prec + 192))
if verbose:
print "P0_ap = %s" % (vector(CC, P0_ap), )
if verbose:
print "Computing AJ of P0..."
c, w = cputime(), walltime()
ajP0 = vector(CCap, AJ1_digits(g, P0_ap, digits))
print "Time: CPU %.2f s, Wall: %.2f s" % (
cputime(c),
walltime(w),
)
print
else:
ajP0 = vector(CCap, AJ1_digits(g, P0_ap, digits))
output['ajP'] = ajP0
aj2P0 = 2 * ajP0
alpha2P0_an = alpha_ap * aj2P0
if verbose:
print "Working over %s" % CCap
invertAJ_tries = 3
for i in range(invertAJ_tries):
#try invertAJ_tries times to invertAJ
try:
if verbose:
print "\n\ninverting AJ..."
c, w = cputime(), walltime()
alpha2P0_div = iaj.invertAJ(alpha2P0_an, power)
print "Time: CPU %.2f s, Wall: %.2f s" % (
cputime(c),
walltime(w),
)
print "\n\n"
else:
alpha2P0_div = iaj.invertAJ(alpha2P0_an, power)
break
except AssertionError as error:
print error
if verbose:
print "an assertion failed while inverting AJ.."
if i == invertAJ_tries - 1:
if verbose:
print "retrying with a new P0"
print
raise ZeroDivisionError
else:
iaj.iajlocal.set_basepoints()
if verbose:
print "retrying again with a new set of base points"
if verbose:
print "Computing the Mumford coordinates of alpha(2*P0 - 2*W)"
c, w = cputime(), walltime()
R0, R1 = alpha2P0_div.coordinates()
print "Time: CPU %.2f s, Wall: %.2f s" % (
cputime(c),
walltime(w),
)
else:
R0, R1 = alpha2P0_div.coordinates()
points = [R0, R1]
x_poly = alpha2P0_div.x_coordinates()
output['R'] = points
output['x_poly'] = x_poly
if (R0 in [+Infinity, -Infinity]) or (R1 in [+Infinity, -Infinity]):
if aggressive:
# we want to avoid these situations
if verbose:
print "One of the coordinates is at infinity"
if R0 in [+Infinity, -Infinity]:
print "R0 = %s" % (R0, )
else:
print "R1 = %s" % (R1, )
print "retrying with a new P0"
print
raise ZeroDivisionError
else:
return output
buffer = "# R0 = %s\n" % (vector(CC, R0), )
buffer += "# R1 = %s\n" % (vector(CC, R1), )
buffer += "# and \n# x_poly = %s\n" % (vector(CC, x_poly), )
if verbose:
print buffer
assert len(x_poly) == 3
algx_poly = [NF_embedding(coeff, L) for coeff in x_poly]
buffer = "algx_poly = %s;\n" % (algx_poly, )
if L != QQ:
buffer += "#where %s ~ %s\n" % (L.gen(), L.gen().complex_embedding())
buffer += "\n"
if verbose:
print buffer
sys.stdout.flush()
sys.stderr.flush()
output['algx_poly'] = algx_poly
if None in algx_poly:
if aggressive:
if verbose:
print "No algebraic expression for the polynomial"
print "retrying with a new P0"
sys.stdout.flush()
sys.stderr.flush()
raise ZeroDivisionError
else:
return output
#c, b, a = algx_poly
#if aggressive and b**2 - 4*a*c == 0:
# raise ZeroDivisionError
if verbose:
print "Done compute_alpha_point()"
return output
def trace_and_norm_ladic(L,
M,
P0,
P1,
P2,
f,
alpha,
degree_bound,
primes=120,
bits=62,
verbose=True):
if verbose:
print "trace_and_norm_ladic()"
print "primes = %d, bits = %d" % (primes, bits)
# Input:
# * L the number field where P0, alpha, norm and trace are defined over
# * M a relative extension of L where P1 and P2 are defined over
# * P0 initial point already embedded in M
# * P1, P2 image points alpha(2 * P0 - \infty) = P1 + P2 - \infty
# * alpha the matrix represing the endomorphism on the tangent space in M
# * f the defining polynomial of the curve such that y^2 = f(x)
# * degree bound for the trace and norm as rational maps
# Note: Due to inconsistencies of the complex embeddings of L and M we require P0 and alpha to be given in M
# Output:
# * [trace_numberator, trace_denominator, norm_numberator, norm_denominator]
# represented as lists of elements in L
for arg in [P0, P1, P2, alpha]:
assert arg.base_ring() is M
hard_bound = 2 * degree_bound + 1
soft_bound = hard_bound + 10
if verbose:
print "hard_bound = %d\nsoft_bound = %d" % (hard_bound, soft_bound)
print "Generating split primes..."
c, w = cputime(), walltime()
ps_roots = random_split_primes(field=L,
bits=bits,
primes=primes,
relative_ext=M.relative_polynomial())
print "Time: CPU %.2f s, Wall: %.2f s" % (
cputime(c),
walltime(w),
)
else:
ps_roots = random_split_primes(field=L,
bits=bits,
primes=primes,
relative_ext=M.relative_polynomial())
to_lift_raw = []
if verbose:
print "Applying newton lift at each prime"
for p_root in ps_roots:
ell, root = p_root
FF = FiniteField(ell)
FF_xell = PolynomialRing(FF, "xell")
Lpoly = FF_xell(
reduce_list_split(M.relative_polynomial().list(), p_root))
assert Lpoly.degree() == len(Lpoly.roots())
Lroot = Lpoly.roots()[0][0].lift()
PSring_ell = PowerSeriesRing(FF, "Tell", default_prec=soft_bound)
P0_ell = vector(FF, reduce_list_split_relative(P0, p_root, Lroot))
P1_ell = vector(FF, reduce_list_split_relative(P1, p_root, Lroot))
P2_ell = vector(FF, reduce_list_split_relative(P2, p_root, Lroot))
f_ell = FF_xell(reduce_list_split(f.list(), p_root))
alpha_ell = reduce_matrix_split_relative(alpha, p_root, Lroot)
x1_ell, x2_ell = newton_linear(P0_ell, P1_ell, P2_ell, f_ell,
alpha_ell, PSring_ell, soft_bound)
trace_series_ell = x1_ell + x2_ell
norm_series_ell = x1_ell * x2_ell
trace_numerator_ell, trace_denominator_ell = rational_reconstruct_poly(
FF_xell(trace_series_ell.list()),
FF_xell.gen()**trace_series_ell.prec())
norm_numerator_ell, norm_denominator_ell = rational_reconstruct_poly(
FF_xell(norm_series_ell.list()),
FF_xell.gen()**norm_series_ell.prec())
# shift the series back to zero
shift = FF_xell.gen() - P0_ell[0]
factors_ell = [
trace_numerator_ell(shift).list(),
trace_denominator_ell(shift).list(),
norm_numerator_ell(shift).list(),
norm_denominator_ell(shift).list()
]
degrees_ell = tuple([len(elt) for elt in factors_ell])
to_lift_raw.append((p_root, degrees_ell, factors_ell))
if verbose:
print "Getting rid of bad primes..."
# get rid of badprimes
degrees_count = {}
for _, degrees_ell, _ in to_lift_raw:
if degrees_ell in degrees_count:
degrees_count[degrees_ell] += 1
else:
degrees_count[degrees_ell] = 1
max_value = 0
max_arg = None
for degrees_ell, count in degrees_count.items():
if count > max_value:
max_arg = degrees_ell
max_value = count
output = [None] * 4
for i, elt in enumerate(max_arg):
output[i] = [0] * elt
to_lift = []
ps_roots = []
for p_root, degrees_ell, factors_ell in to_lift_raw:
if degrees_ell == max_arg:
ps_roots.append(p_root)
to_lift.append(factors_ell)
extra_factor = to_lift[-1]
extra_p_root = ps_roots[-1]
to_lift = to_lift[:-1]
ps_roots = ps_roots[:-1]
OL = L.ring_of_integers()
p_ideals = [OL.ideal(p,
L.gen() - r) for p, r in ps_roots]
I = prod(p_ideals)
if L is QQ:
BI_coordinates = None
else:
BI = I.basis()
# basis as a ZZ-module
BI_coordinates = [OL.coordinates(b) for b in BI]
if verbose:
print "Lifting everything"
for i, lift in enumerate(output):
for j, elt in enumerate(lift):
residues = [residue[i][j] for residue in to_lift]
output[i][j] = fractional_CRT_split(residues=residues,
ps_roots=ps_roots,
K=L,
BI_coordinates=BI_coordinates)
assert reduce_constant_split(output[i][j],
extra_p_root) == extra_factor[i][j]
if verbose:
print "trace_and_norm_ladic() Done"
return output
def __init__(self, p, congruence_type=1, sign=1, algorithm="custom", verbose=False, dump_dir=None):
"""
Create a Kamienny criterion object.
INPUT:
- `p` -- prime -- verify that there is no order p torsion
over a degree `d` field
- `sign` -- 1 (default),-1 or 0 -- the sign of the modular symbols space to use
- ``algorithm`` -- "default" or "custom" whether to use a custom (faster)
integral structure algorithm or to use the sage builtin algortihm
- ``verbose`` -- bool; whether to print extra stuff while
running.
EXAMPLES::
sage: from mdsage import *
sage: C = KamiennyCriterion(29, algorithm="custom", verbose=False); C
Kamienny's Criterion for p=29
sage: C.use_custom_algorithm
True
sage: C.p
29
sage: C.verbose
False
"""
self.verbose = verbose
self.dump_dir = dump_dir
if self.verbose: tm = cputime(); mem = get_memory_usage(); print "init"
assert congruence_type == 0 or congruence_type == 1
self.congruence_type=congruence_type
try:
p = ZZ(p)
if congruence_type==0:
self.congruence_group = Gamma0(p)
if congruence_type==1:
self.congruence_group = GammaH(p,[-1])
except TypeError:
self.congruence_group = GammaH(p.level(),[-1]+p._generators_for_H())
self.congruence_type = ("H",self.congruence_group._list_of_elements_in_H())
self.p = self.congruence_group.level()
self.algorithm=algorithm
self.sign=sign
self.M = ModularSymbols(self.congruence_group, sign=sign)
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "modsym"
self.S = self.M.cuspidal_submodule()
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "cuspsub"
self.use_custom_algorithm = False
if algorithm=="custom":
self.use_custom_algorithm = True
if self.use_custom_algorithm:
int_struct = self.integral_cuspidal_subspace()
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "custom int_struct"
else:
int_struct = self.S.integral_structure()
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "sage int_struct"
self.S_integral = int_struct
v = VectorSpace(GF(2), self.S.dimension()).random_element()
self.v=v
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "rand_vect"
if dump_dir:
v.dump(dump_dir+"/vector%s_%s" % (p,congruence_type))
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "dump"
def silke(A, c, beta, h, m=None, scale=1, float_type="double"):
"""
:param A: LWE matrix
:param c: LWE vector
:param beta: BKW block size
:param m: number of samples to consider
:param scale: scale rhs of lattice by this factor
"""
from fpylll import BKZ, IntegerMatrix, LLL, GSO
from fpylll.algorithms.bkz2 import BKZReduction as BKZ2
if m is None:
m = A.nrows()
L = dual_instance1(A, scale=scale)
L = IntegerMatrix.from_matrix(L)
L = LLL.reduction(L, flags=LLL.VERBOSE)
M = GSO.Mat(L, float_type=float_type)
bkz = BKZ2(M)
t = 0.0
param = BKZ.Param(block_size=beta,
strategies=BKZ.DEFAULT_STRATEGY,
auto_abort=True,
max_loops=16,
flags=BKZ.VERBOSE | BKZ.AUTO_ABORT | BKZ.MAX_LOOPS)
bkz(param)
t += bkz.stats.total_time
H = copy(L)
import pickle
pickle.dump(L, open("L-%d-%d.sobj" % (L.nrows, beta), "wb"))
E = []
Y = set()
V = set()
y_i = vector(ZZ, tuple(L[0]))
Y.add(tuple(y_i))
E.append(apply_short1(y_i, A, c, scale=scale)[1])
v = L[0].norm()
v_ = v / sqrt(L.ncols)
v_r = 3.2 * sqrt(L.ncols - A.ncols()) * v_ / scale
v_l = sqrt(h) * v_
fmt = u"{\"t\": %5.1fs, \"log(sigma)\": %5.1f, \"log(|y|)\": %5.1f, \"log(E[sigma]):\" %5.1f}"
print
print fmt % (t, log(abs(E[-1]), 2), log(L[0].norm(),
2), log(sqrt(v_r**2 + v_l**2), 2))
print
for i in range(m):
t = cputime()
M = GSO.Mat(L, float_type=float_type)
bkz = BKZ2(M)
t = cputime()
bkz.randomize_block(0, L.nrows, stats=None, density=3)
LLL.reduction(L)
y_i = vector(ZZ, tuple(L[0]))
l_n = L[0].norm()
if L[0].norm() > H[0].norm():
L = copy(H)
t = cputime(t)
Y.add(tuple(y_i))
V.add(y_i.norm())
E.append(apply_short1(y_i, A, c, scale=scale)[1])
if len(V) >= 2:
fmt = u"{\"i\": %4d, \"t\": %5.1fs, \"log(|e_i|)\": %5.1f, \"log(|y_i|)\": %5.1f,"
fmt += u"\"log(sigma)\": (%5.1f,%5.1f), \"log(|y|)\": (%5.1f,%5.1f), |Y|: %5d}"
print fmt % (i + 2, t, log(abs(E[-1]), 2), log(
l_n,
2), log_mean(E), log_var(E), log_mean(V), log_var(V), len(Y))
return E
def check_unproven_ranks(jobs=1,
jobid=0,
use_weak_bsd=False,
skip_real_char=False):
todo = list(
db.mf_newforms.search({
u'analytic_rank': {
'$gt': int(1)
},
u'analytic_rank_proved': False
}))
todo2 = []
todo3 = []
todo4 = []
cnt = 0
vcnt = 0
for i in range(len(todo)):
if i % jobs != jobid:
continue
start = cputime()
data = todo[i]
if skip_real_char and data[u"char_is_real"]:
continue
if use_weak_bsd and data[u'weight'] == 2 and data[
u'dim'] == 1 and data[u'char_orbit_index'] == 1:
ec_label = "%d.%s1" % (
data[u'level'], cremona_letter_code(data[u'hecke_orbit'] - 1))
r = db.ec_curves.lookup(ec_label)[u'rank']
if data[u'analytic_rank'] != r:
print "*** winding element is nonzero, positive analytic rank %d for newform %s appears to be wrong ***" % (
data[u'rank'], data[u'label'])
print data[u'label']
todo2.append(data[u'label'])
else:
print "verified that analytic rank %d of newform %s matches Mordell-Weil rank of elliptic curve %s" % (
data[u'analytic_rank'], data[u'label'], ec_label)
continue
print "Checking newform %s of dimension %d with analytic rank <= %d..." % (
data[u'label'], data[u'dim'], data[u'analytic_rank'])
w = windingelement_hecke_cutter_projected(data, extra_cutter_bound=100)
if w != 0:
print "*** winding element is nonzero, positive analytic rank %d for newform %s appears to be wrong ***" % (
data[u'rank'], data[u'label'])
print data[u'label']
todo2.append(data[u'label'])
else:
if data[u'analytic_rank'] == 2 and data["is_self_dual"]:
print "Verified analytic rank is 2."
vcnt += 1
else:
print "Verified analytic rank > 0"
todo3.append(data[u'label'])
print "Processed newform %s in %.3f CPU seconds" % (data[u'label'],
cputime() - start)
cnt += 1
todo = list(
db.mf_newforms.search({
u'analytic_rank': int(1),
u'is_self_dual': False,
u'analytic_rank_proved': False
}))
for i in range(len(todo)):
if i % jobs != jobid:
continue
start = cputime()
data = todo[i]
if skip_real_char and data[u"char_is_real"]:
continue
print "Checking non-self-dual newform %s of dimension %d with analytic rank <= %d..." % (
data[u'label'], data[u'dim'], data[u'analytic_rank'])
w = windingelement_hecke_cutter_projected(data, extra_cutter_bound=100)
if w != 0:
print "*** winding element is nonzero, positive analytic rank appears to be wrong ***"
print data[u'label']
todo4.append(data[u'label'])
else:
print "Verified analytic rank is 1."
vcnt += 1
print "Processed newform %s in %.3f CPU seconds" % (data[u'label'],
cputime() - start)
cnt += 1
print "Checked analytic ranks of %d newforms, of which %d were verified" % (
cnt, vcnt)
if len(todo2) > 0 or len(todo4) > 0:
print "The following newforms appear to have the wrong analytic rank:"
for r in todo2:
print " %s (claimed analytic rank %d)" % (r[u'lable'],
r[u'analytic_rank'])
for r in todo4:
print " %s (claimed analytic rank %d)" % (r[u'lable'],
r[u'analytic_rank'])
if len(todo3) > 0:
print "The following newforms have positive but unverified analytic ranks:"
for r in todo2:
print " %s (claimed analytic rank %d, proved nonzero)" % (
r[u'lable'], r[u'analytic_rank'])
def solve(self, beta, max_iterations=100, tolerance=None, x0=None):
# solve \sum_j (\int_bj ^{P_j} w_i)_i = beta
# assumes beta is small
if tolerance == None:
tolerance = mpmath.mpf(2)**(-mpmath.mp.prec + 3)
#print "tolerance = %s" % tolerance
beta = mpmath.matrix([b for b in beta])
while True:
try:
basepoints = self.get_basepoints()
if x0 is None:
x = mpmath.matrix([b[0] for b in basepoints])
value = mpmath.matrix([0 for _ in range(self.genus)])
else:
assert len(x0) == self.genus
x = mpmath.matrix(x0)
if self.verbose:
c, w = cputime(), walltime()
value = self.to_J_sum(x)
print "Time: CPU %.2f s, Wall: %.2f s" % (
cputime(c),
walltime(w),
)
else:
value = self.to_J_sum(x)
previous_norm = 1
divg_bound = 3
divergingQ = 0
for k in range(max_iterations):
J = self.jacobian(x)
# J y = f(x) - beta
y = mpmath.lu_solve(J, value - beta)
x = x - y
norm = mpmath.norm(y) / mpmath.norm(x)
if self.verbose:
print "k = %d norm = %.3e" % (k, norm)
if norm < tolerance:
return (x, y)
if norm / previous_norm > 1.5:
divergingQ += 1
else:
divergingQ = 0
previous_norm = norm
if divergingQ > divg_bound:
raise RuntimeWarning(
"method failed: the error diverged")
if self.verbose:
c, w = cputime(), walltime()
value = self.to_J_sum(x)
print "Time: CPU %.2f s, Wall: %.2f s" % (
cputime(c),
walltime(w),
)
else:
value = self.to_J_sum(x)
else:
raise RuntimeWarning(
"method failed: max number of iterations reached")
except NotImplementedError as e:
print e
print "Generating new basepoints"
self.set_basepoints()
def t1_prime(self, n=5, p=65521):
"""
Return a multiple of element t1 of the Hecke algebra mod 2,
computed using the Hecke operator $T_n$, where n is self.n.
To make computation faster we only check if ...==0 mod p.
Hence J will contain more elements, hence we get a multiple.
INPUT:
- `n` -- integer (optional default=5)
- `p` -- prime (optional default=65521)
OUTPUT:
- a mod 2 matrix
EXAMPLES::
sage: from mdsage import *
sage: C = KamiennyCriterion(29)
sage: C.t1_prime()
22 x 22 dense matrix over Finite Field of size 2 (use the '.str()' method to see the entries)
sage: C.t1_prime(n=3) == 1
True
sage: C = KamiennyCriterion(37)
sage: C.t1_prime()[0]
(1, 1, 1, 0, 0, 1, 1, 1, 0, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0)
"""
if self.verbose: tm = cputime(); mem = get_memory_usage(); print "t1 start"
T = self.S.hecke_matrix(n)
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "hecke 1"
f = self.hecke_polynomial(n) # this is the same as T.charpoly()
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "char 1"
Fint = f.factor()
if all(i[1]!=1 for i in Fint):
return matrix_modp(zero_matrix(T.nrows()))
# raise ValueError("T_%s needs to be a generator of the hecke algebra"%n)
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "factor 1, Fint = %s"%(Fint)
R = f.parent().change_ring(GF(p))
F = Fint.base_change(R)
# Compute the iterators of T acting on the winding element.
e = self.M([0, oo]).element().dense_vector().change_ring(GF(p))
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "wind"
t = matrix_modp(self.M.hecke_matrix(n).dense_matrix(), p)
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "hecke 2"
g = t.charpoly()
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "char 2"
Z = t.iterates(e, t.nrows(), rows=True)
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "iter"
# We find all factors F[i][0] for f such that
# (g/F[i][0])(t) * e = 0.
# We do this by computing the polynomial
# h = g/F[i][0],
# turning it into a vector v, and computing
# the matrix product v * Z. If the product
# is 0, then e is killed by h(t).
J = []
for i in range(len(F)):
if F[i][1]!=1:
J.append(i)
continue
h, r = g.quo_rem(F[i][0] ** F[i][1])
assert r == 0
v = vector(GF(p), h.padded_list(t.nrows()))
if v * Z == 0:
J.append(i)
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "zero check"
if self.verbose: print "J =", J
if len(J) == 0:
# The annihilator of e is the 0 ideal.
return matrix_modp(identity_matrix(T.nrows()))
# Finally compute t1. I'm concerned about how
# long this will take, so we reduce T mod 2 first.
# It is important to call "self.T(2)" to get the mod-2
# reduction of T2 with respect to the right basis (e.g., the
# integral basis in case use_integral_structure is true.
Tmod2 = self.T(n)
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "hecke mod"
g = prod(Fint[i][0].change_ring(GF(2)) ** Fint[i][1] for i in J)
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "g has degree %s"%(g.degree())
t1 = g(Tmod2)
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "t1 finnished"
return t1
def verify_criterion(self, d, t=None, n=5, p=65521, q=3, v=None, use_rand_vec=False, verbose=False):
"""
Attempt to verify the criterion at p using the input t. If t is not
given compute it using n, p and q
INPUT:
- `t` -- hecke operator (optional default=None)
- `n` -- integer (optional default=5), used in computing t1
- `p` -- prime (optional default=46337), used in computing t1
- `q` -- prime (optional default=3), used in computing t2
- `verbose` -- bool (default: True); if true, print to
stdout as the computation is performed.
OUTPUT:
- bool -- True if criterion satisfied; otherwise, False
- string -- message about what happened or went wrong
EXAMPLES:
We can't get p=29 to work no matter what I try, which nicely illustrates
the various ways the criterion can fail::
sage: from mdsage import *
sage: C = KamiennyCriterion(29)
sage: C.verify_criterion(4,n=5)
dependency dimension to large to search through
(False,
'There is a dependency of weigt 2 in dependencies(3,1)',
[Vector space of degree 4 and dimension 0 over Finite Field of size 2
Basis matrix:
[], Vector space of degree 16 and dimension 8 over Finite Field of size 2
Basis matrix:
[1 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0]
[0 1 0 0 0 0 1 0 1 1 0 1 1 1 0 0]
[0 0 1 0 0 0 1 0 0 0 0 0 0 0 0 0]
[0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 0]
[0 0 0 0 1 0 1 0 1 1 0 1 1 1 0 0]
[0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0]
[0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0]
[0 0 0 0 0 0 0 0 0 0 1 0 1 0 0 0], Vector space of degree 28 and dimension 19 over Finite Field of size 2
Basis matrix:
[1 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 1 1 1]
[0 1 0 0 0 0 0 0 0 1 0 0 0 1 0 0 0 0 0 0 1 0 1 0 0 1 1 0]
[0 0 1 0 0 0 0 0 0 1 0 0 1 0 0 0 0 0 0 0 1 0 0 1 0 0 1 0]
[0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0]
[0 0 0 0 1 0 0 0 0 1 0 0 0 1 0 0 0 0 0 0 1 0 1 0 0 1 1 0]
[0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0]
[0 0 0 0 0 0 1 0 0 1 0 0 1 0 0 0 0 0 0 0 1 0 0 1 0 0 1 0]
[0 0 0 0 0 0 0 1 0 1 0 0 1 1 0 0 0 0 0 0 0 0 1 1 0 0 1 1]
[0 0 0 0 0 0 0 0 1 1 0 0 1 1 0 0 0 0 0 0 0 0 1 1 0 0 1 1]
[0 0 0 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0]
[0 0 0 0 0 0 0 0 0 0 0 1 1 1 0 0 0 0 0 0 0 0 0 0 0 1 1 1]
[0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 1 0 0]
[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 1 0 1 1 0 1 1 1]
[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 1 0 0 0 0 0 0 0]
[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0]
[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 1 1 0 1 1 1]
[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1]
[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0]
[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0]])
With p=43 the criterion is satisfied for d=4, thus proving that 43 is
not the order of a torsion point on any elliptic curve over
a quartic field::
sage: C = KamiennyCriterion(43); C
Kamienny's Criterion for p=43
sage: C.verify_criterion(4)
(True,
'All conditions are satified for Gamma1 d=4 p=43. Using n=5, modp=65521, q=3 in Kamienny Version 1.5 and SageMath version ...',
[Vector space of degree 4 and dimension 0 over Finite Field of size 2
Basis matrix:
[], Vector space of degree 23 and dimension 2 over Finite Field of size 2
Basis matrix:
[1 1 0 1 0 0 1 1 1 0 1 0 1 1 1 1 1 1 0 0 1 0 0]
[0 0 1 0 1 1 1 0 1 1 0 1 1 1 1 0 1 1 1 1 0 0 0], Vector space of degree 42 and dimension 11 over Finite Field of size 2
Basis matrix:
[1 0 0 0 0 0 0 1 0 1 1 1 0 1 1 0 1 0 1 0 1 0 0 0 0 0 1 0 1 0 0 0 1 1 0 0 1 1 1 1 1 1]
[0 1 0 0 0 0 0 0 0 1 0 1 0 1 0 1 1 0 0 0 0 0 1 0 1 1 0 0 1 0 0 0 1 1 1 1 0 0 0 1 0 0]
[0 0 1 0 0 0 0 0 0 1 0 0 0 0 0 1 1 1 0 0 1 0 0 0 0 0 0 0 0 1 1 1 0 0 0 0 1 1 0 0 1 0]
[0 0 0 1 0 0 0 0 0 1 0 0 0 0 1 1 1 0 1 0 0 0 0 0 1 1 0 0 1 0 0 0 0 1 0 1 0 0 0 1 0 0]
[0 0 0 0 1 0 0 1 0 1 0 0 1 0 0 1 1 0 0 0 0 0 0 0 0 1 0 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0]
[0 0 0 0 0 1 0 1 0 0 0 1 1 0 0 1 1 1 1 1 1 0 1 0 0 1 1 0 0 1 1 1 0 0 1 0 0 0 1 1 0 1]
[0 0 0 0 0 0 1 0 0 0 1 0 1 1 1 0 1 1 0 1 0 0 1 0 0 0 1 0 1 0 1 0 0 1 1 0 0 0 1 1 1 1]
[0 0 0 0 0 0 0 0 1 1 1 0 0 0 0 1 1 0 0 1 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 1 1 0 0 0 0]
[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 1 0 0 0 1 0 0 1 0 0 0 0 1 0 0 0 0 1]
[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 1 0 0 0 1 0 1 0 0 0 0 0 0 1 1 0]
[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 0 0 1 1 1 0 1 1 0 0 0]])
"""
if self.verbose: tm = cputime(); mem = get_memory_usage(); print "verif start"
if self.p < (1 + 2 ** (d / 2)) ** 2 and self.verbose:
print "WARNING: p must be at least (1+2^(d/2))^2 for the criterion to work."
if t == None:
t = self.t(n, p, q)
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "t"
if v==None:
if use_rand_vec:
v=self.v
else:
v=t.parent()(1)
if self.congruence_type==0:
verified,message,dependencies=self.verify_gamma0(d,t,v)
else:
verified,message,dependencies=self.verify_gamma1(d,t,v)
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "total verif time"
if not verified:
return verified,message,dependencies
return True, "All conditions are satified for Gamma%s d=%s p=%s. Using n=%s, modp=%s, q=%s in Kamienny Version %s and %s" % (self.congruence_type,d, self.p, n, p, q, Kamienny_Version, version()),dependencies
def verify_criterion(self, d, t=None, n=5, p=65521, q=3, v=None, use_rand_vec=False, verbose=False):
"""
Attempt to verify the criterion at p using the input t. If t is not
given compute it using n, p and q
INPUT:
- `t` -- hecke operator (optional default=None)
- `n` -- integer (optional default=5), used in computing t1
- `p` -- prime (optional default=46337), used in computing t1
- `q` -- prime (optional default=3), used in computing t2
- `verbose` -- bool (default: True); if true, print to
stdout as the computation is performed.
OUTPUT:
- bool -- True if criterion satisfied; otherwise, False
- string -- message about what happened or went wrong
EXAMPLES:
We can't get p=29 to work no matter what I try, which nicely illustrates
the various ways the criterion can fail::
sage: from mdsage import *
sage: C = KamiennyCriterion(29)
sage: C.verify_criterion(4,n=5)
dependency dimension to large to search through
(False,
'There is a dependency of weigt 2 in dependencies(3,1)',
[Vector space of degree 4 and dimension 0 over Finite Field of size 2
Basis matrix:
[], Vector space of degree 16 and dimension 8 over Finite Field of size 2
Basis matrix:
[1 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0]
[0 1 0 0 0 0 1 0 1 1 0 1 1 1 0 0]
[0 0 1 0 0 0 1 0 0 0 0 0 0 0 0 0]
[0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 0]
[0 0 0 0 1 0 1 0 1 1 0 1 1 1 0 0]
[0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0]
[0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0]
[0 0 0 0 0 0 0 0 0 0 1 0 1 0 0 0], Vector space of degree 28 and dimension 19 over Finite Field of size 2
Basis matrix:
[1 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 1 1 1]
[0 1 0 0 0 0 0 0 0 1 0 0 0 1 0 0 0 0 0 0 1 0 1 0 0 1 1 0]
[0 0 1 0 0 0 0 0 0 1 0 0 1 0 0 0 0 0 0 0 1 0 0 1 0 0 1 0]
[0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0]
[0 0 0 0 1 0 0 0 0 1 0 0 0 1 0 0 0 0 0 0 1 0 1 0 0 1 1 0]
[0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0]
[0 0 0 0 0 0 1 0 0 1 0 0 1 0 0 0 0 0 0 0 1 0 0 1 0 0 1 0]
[0 0 0 0 0 0 0 1 0 1 0 0 1 1 0 0 0 0 0 0 0 0 1 1 0 0 1 1]
[0 0 0 0 0 0 0 0 1 1 0 0 1 1 0 0 0 0 0 0 0 0 1 1 0 0 1 1]
[0 0 0 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0]
[0 0 0 0 0 0 0 0 0 0 0 1 1 1 0 0 0 0 0 0 0 0 0 0 0 1 1 1]
[0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 1 0 0]
[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 1 0 1 1 0 1 1 1]
[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 1 0 0 0 0 0 0 0]
[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0]
[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 1 1 0 1 1 1]
[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1]
[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0]
[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0]])
With p=43 the criterion is satisfied for d=4, thus proving that 43 is
not the order of a torsion point on any elliptic curve over
a quartic field::
sage: C = KamiennyCriterion(43); C
Kamienny's Criterion for p=43
sage: C.verify_criterion(4)
(True,
'All conditions are satified for Gamma1 d=4 p=43. Using n=5, modp=65521, q=3 in Kamienny Version 1.5 and SageMath version ...',
[Vector space of degree 4 and dimension 0 over Finite Field of size 2
Basis matrix:
[], Vector space of degree 23 and dimension 2 over Finite Field of size 2
Basis matrix:
[1 1 0 1 0 0 1 1 1 0 1 0 1 1 1 1 1 1 0 0 1 0 0]
[0 0 1 0 1 1 1 0 1 1 0 1 1 1 1 0 1 1 1 1 0 0 0], Vector space of degree 42 and dimension 11 over Finite Field of size 2
Basis matrix:
[1 0 0 0 0 0 0 1 0 1 1 1 0 1 1 0 1 0 1 0 1 0 0 0 0 0 1 0 1 0 0 0 1 1 0 0 1 1 1 1 1 1]
[0 1 0 0 0 0 0 0 0 1 0 1 0 1 0 1 1 0 0 0 0 0 1 0 1 1 0 0 1 0 0 0 1 1 1 1 0 0 0 1 0 0]
[0 0 1 0 0 0 0 0 0 1 0 0 0 0 0 1 1 1 0 0 1 0 0 0 0 0 0 0 0 1 1 1 0 0 0 0 1 1 0 0 1 0]
[0 0 0 1 0 0 0 0 0 1 0 0 0 0 1 1 1 0 1 0 0 0 0 0 1 1 0 0 1 0 0 0 0 1 0 1 0 0 0 1 0 0]
[0 0 0 0 1 0 0 1 0 1 0 0 1 0 0 1 1 0 0 0 0 0 0 0 0 1 0 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0]
[0 0 0 0 0 1 0 1 0 0 0 1 1 0 0 1 1 1 1 1 1 0 1 0 0 1 1 0 0 1 1 1 0 0 1 0 0 0 1 1 0 1]
[0 0 0 0 0 0 1 0 0 0 1 0 1 1 1 0 1 1 0 1 0 0 1 0 0 0 1 0 1 0 1 0 0 1 1 0 0 0 1 1 1 1]
[0 0 0 0 0 0 0 0 1 1 1 0 0 0 0 1 1 0 0 1 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 1 1 0 0 0 0]
[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 1 0 0 0 1 0 0 1 0 0 0 0 1 0 0 0 0 1]
[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 1 0 0 0 1 0 1 0 0 0 0 0 0 1 1 0]
[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 0 0 1 1 1 0 1 1 0 0 0]])
"""
if self.verbose: tm = cputime(); mem = get_memory_usage(); print("verif start")
if self.p < (1 + 2 ** (d / 2)) ** 2 and self.verbose:
print("WARNING: p must be at least (1+2^(d/2))^2 for the criterion to work.")
if t == None:
t = self.t(n, p, q)
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "t")
if v==None:
if use_rand_vec:
v=self.v
else:
v=t.parent()(1)
if self.congruence_type==0:
verified,message,dependencies=self.verify_gamma0(d,t,v)
else:
verified,message,dependencies=self.verify_gamma1(d,t,v)
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "total verif time")
if not verified:
return verified,message,dependencies
return True, "All conditions are satified for Gamma%s d=%s p=%s. Using n=%s, modp=%s, q=%s in Kamienny Version %s and %s" % (self.congruence_type,d, self.p, n, p, q, Kamienny_Version, version()),dependencies
def process_curve_standalone(label,
digits=600,
power=15,
verbose=True,
internalverbose=False,
folder=None):
import os
set_random_seed(1)
import random
random.seed(1)
C = lmfdb.getDBconnection()
curve = C.genus2_curves.curves.find_one({'label': label})
if curve is None:
print "Wrong label"
return 2
endo_alg = curve['real_geom_end_alg']
# deals with the default folders
if folder is None:
if not '__datadir__' in globals():
import os
import inspect
filename = inspect.getframeinfo(inspect.currentframe())[0]
__datadir__ = os.path.dirname(filename) + "/data/"
base_folder = __datadir__
if endo_alg == 'R':
print "End = QQ, Nothing to do"
return 0
elif endo_alg == 'R x R':
if curve['is_simple_geom']:
type_folder = 'simple/RM'
else:
type_folder = 'split/nonCM_times_nonCM'
elif endo_alg == 'C x R':
type_folder = 'split/CM_times_nonCM'
elif endo_alg == 'C x C':
if curve['is_simple_geom']:
type_folder = 'simple/CM'
else:
type_folder = 'split/CM_times_CM'
elif endo_alg == 'M_2(R)':
if curve['is_simple_geom']:
type_folder = 'simple/QM'
else:
type_folder = 'split/nonCM_square'
elif endo_alg == 'M_2(C)':
type_folder = 'split/CM_square'
else:
print "did I forget a case?"
return 1
folder = os.path.join(base_folder, type_folder)
if not os.path.exists(folder):
print "Creating dir: %s" % folder
os.makedirs(folder)
assert os.path.exists(folder)
#filenames
stdout_filename = os.path.join(folder, label + ".stdout")
stderr_filename = os.path.join(folder, label + ".stderr")
output_filename = os.path.join(folder, label + ".sage")
sys.stdout = open(stdout_filename, 'w', int(0))
sys.stderr = open(stderr_filename, 'w')
c, w = cputime(), walltime()
data, sout, verified = process_curve_lmfdb(curve,
digits,
power=power,
verbose=True,
internalverbose=False)
print "Time: CPU %.2f s, Wall: %.2f s" % (
cputime(c),
walltime(w),
)
output_file = open(output_filename, 'w')
output_file.write(sout)
output_file.close()
sys.stdout.flush()
os.fsync(sys.stdout.fileno())
sys.stderr.flush()
os.fsync(sys.stderr.fileno())
sys.stdout = sys.__stdout__
sys.stderr = sys.__stderr__
print "Done: label = %s, verified = %s" % (label, verified)
print os.popen("tail -n 1 %s" % stdout_filename).read()
if verified:
return 0
else:
return 1
def silke(A, c, beta, h, m=None, scale=1, float_type="double"):
"""
:param A: LWE matrix
:param c: LWE vector
:param beta: BKW block size
:param m: number of samples to consider
:param scale: scale rhs of lattice by this factor
"""
from fpylll import BKZ, IntegerMatrix, LLL, GSO
from fpylll.algorithms.bkz2 import BKZReduction as BKZ2
if m is None:
m = A.nrows()
L = dual_instance1(A, scale=scale)
L = IntegerMatrix.from_matrix(L)
L = LLL.reduction(L, flags=LLL.VERBOSE)
M = GSO.Mat(L, float_type=float_type)
bkz = BKZ2(M)
t = 0.0
param = BKZ.Param(block_size=beta,
strategies=BKZ.DEFAULT_STRATEGY,
auto_abort=True,
max_loops=16,
flags=BKZ.VERBOSE|BKZ.AUTO_ABORT|BKZ.MAX_LOOPS)
bkz(param)
t += bkz.stats.total_time
H = copy(L)
import pickle
pickle.dump(L, open("L-%d-%d.sobj"%(L.nrows, beta), "wb"))
E = []
Y = set()
V = set()
y_i = vector(ZZ, tuple(L[0]))
Y.add(tuple(y_i))
E.append(apply_short1(y_i, A, c, scale=scale)[1])
v = L[0].norm()
v_ = v/sqrt(L.ncols)
v_r = 3.2*sqrt(L.ncols - A.ncols())*v_/scale
v_l = sqrt(h)*v_
fmt = u"{\"t\": %5.1fs, \"log(sigma)\": %5.1f, \"log(|y|)\": %5.1f, \"log(E[sigma]):\" %5.1f}"
print
print fmt%(t,
log(abs(E[-1]), 2),
log(L[0].norm(), 2),
log(sqrt(v_r**2 + v_l**2), 2))
print
for i in range(m):
t = cputime()
M = GSO.Mat(L, float_type=float_type)
bkz = BKZ2(M)
t = cputime()
bkz.randomize_block(0, L.nrows, stats=None, density=3)
LLL.reduction(L)
y_i = vector(ZZ, tuple(L[0]))
l_n = L[0].norm()
if L[0].norm() > H[0].norm():
L = copy(H)
t = cputime(t)
Y.add(tuple(y_i))
V.add(y_i.norm())
E.append(apply_short1(y_i, A, c, scale=scale)[1])
if len(V) >= 2:
fmt = u"{\"i\": %4d, \"t\": %5.1fs, \"log(|e_i|)\": %5.1f, \"log(|y_i|)\": %5.1f,"
fmt += u"\"log(sigma)\": (%5.1f,%5.1f), \"log(|y|)\": (%5.1f,%5.1f), |Y|: %5d}"
print fmt%(i+2, t, log(abs(E[-1]), 2), log(l_n, 2), log_mean(E), log_var(E), log_mean(V), log_var(V), len(Y))
return E
def t1_prime(self, n=5, p=65521):
"""
Return a multiple of element t1 of the Hecke algebra mod 2,
computed using the Hecke operator $T_n$, where n is self.n.
To make computation faster we only check if ...==0 mod p.
Hence J will contain more elements, hence we get a multiple.
INPUT:
- `n` -- integer (optional default=5)
- `p` -- prime (optional default=65521)
OUTPUT:
- a mod 2 matrix
EXAMPLES::
sage: from mdsage import *
sage: C = KamiennyCriterion(29)
sage: C.t1_prime()
22 x 22 dense matrix over Finite Field of size 2 (use the '.str()' method to see the entries)
sage: C.t1_prime(n=3) == 1
True
sage: C = KamiennyCriterion(37)
sage: C.t1_prime()[0]
(1, 1, 1, 0, 0, 1, 1, 1, 0, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0)
"""
if self.verbose: tm = cputime(); mem = get_memory_usage(); print("t1 start")
T = self.S.hecke_matrix(n)
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "hecke 1")
f = self.hecke_polynomial(n) # this is the same as T.charpoly()
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "char 1")
Fint = f.factor()
if all(i[1]!=1 for i in Fint):
return matrix_modp(zero_matrix(T.nrows()))
# raise ValueError("T_%s needs to be a generator of the hecke algebra"%n)
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "factor 1, Fint = %s"%(Fint))
R = f.parent().change_ring(GF(p))
F = Fint.base_change(R)
# Compute the iterators of T acting on the winding element.
e = self.M([0, oo]).element().dense_vector().change_ring(GF(p))
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "wind")
t = matrix_modp(self.M.hecke_matrix(n).dense_matrix(), p)
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "hecke 2")
g = t.charpoly()
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "char 2")
Z = t.iterates(e, t.nrows(), rows=True)
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "iter")
# We find all factors F[i][0] for f such that
# (g/F[i][0])(t) * e = 0.
# We do this by computing the polynomial
# h = g/F[i][0],
# turning it into a vector v, and computing
# the matrix product v * Z. If the product
# is 0, then e is killed by h(t).
J = []
for i in range(len(F)):
if F[i][1]!=1:
J.append(i)
continue
h, r = g.quo_rem(F[i][0] ** F[i][1])
assert r == 0
v = vector(GF(p), h.padded_list(t.nrows()))
if v * Z == 0:
J.append(i)
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "zero check")
if self.verbose: print("J =", J)
if len(J) == 0:
# The annihilator of e is the 0 ideal.
return matrix_modp(identity_matrix(T.nrows()))
# Finally compute t1. I'm concerned about how
# long this will take, so we reduce T mod 2 first.
# It is important to call "self.T(2)" to get the mod-2
# reduction of T2 with respect to the right basis (e.g., the
# integral basis in case use_integral_structure is true.
Tmod2 = self.T(n)
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "hecke mod")
g = prod(Fint[i][0].change_ring(GF(2)) ** Fint[i][1] for i in J)
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "g has degree %s"%(g.degree()))
t1 = g(Tmod2)
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "t1 finnished")
return t1
def integral_cuspidal_subspace(self):
"""
In certatain cases this might return the integral structure of the cuspidal subspace.
This code is mainly a way to compute the integral structe faster than sage does now.
It returns None if it cannot find the integral subspace.
"""
if self.verbose: tm = cputime(); mem = get_memory_usage(); print "Int struct start"
#This code is the same as the firs part of self.M.integral_structure
G = set([i for i, _ in self.M._mod2term])
G = list(G)
G.sort()
#if there is a two term relation between two manin symbols we only need one of the two
#so that's why we only use elements from G instead of all manin symbols.
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "G"
B = self.M._manin_gens_to_basis.matrix_from_rows(list(G)).sparse_matrix()
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "B"
#The collums of B now span self.M.integral_structure as ZZ-module
B, d = B._clear_denom()
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "Clear denom"
if d == 1:
#for explanation see d == 2
assert len(set([B.nonzero_positions_in_row(i)[0] for i in xrange(B.nrows()) if len(B.nonzero_positions_in_row(i)) == 1 and B[i, B.nonzero_positions_in_row(i)[0]] == 1])) == B.ncols(), "B doesn't contain the Identity"
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "Check Id"
ZZbasis = MatrixSpace(QQ, B.ncols(), sparse=True)(1)
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "ZZbasis"
elif d == 2:
#in this case the matrix B will contain 2*Id as a minor this allows us to compute the hermite normal form of B in a very efficient way. This will give us the integral basis ZZbasis.
#if it turns out to be nessecarry this can be generalized to the case d%4==2 if we don't mind to only get the right structure localized at 2
assert len(set([B.nonzero_positions_in_row(i)[0] for i in xrange(B.nrows()) if len(B.nonzero_positions_in_row(i)) == 1 and B[i, B.nonzero_positions_in_row(i)[0]] == 2])) == B.ncols(), "B doesn't contain 2*Identity"
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "Check 2*Id"
E = matrix_modp(B,sparse=True)
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "matmodp"
E = E.echelon_form()
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "echelon"
ZZbasis = MatrixSpace(QQ, B.ncols(), sparse=True)(1)
for (pivot_row, pivot_col) in zip(E.pivot_rows(), E.pivots()):
for j in E.nonzero_positions_in_row(pivot_row):
ZZbasis[pivot_col, j] = QQ(1) / 2
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "ZZbasis"
else:
return None
#now we compute the integral kernel of the boundary map with respect to the integral basis. This will give us the integral cuspidal submodule.
boundary_matrix = self.M.boundary_map().matrix()
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "Boundary matrix"
ZZboundary_matrix=(ZZbasis*boundary_matrix).change_ring(ZZ)
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "ZZBoundary matrix"
left_kernel_matrix=ZZboundary_matrix.transpose().dense_matrix()._right_kernel_matrix(algorithm='pari')
if type(left_kernel_matrix)==tuple:
left_kernel_matrix=left_kernel_matrix[1]
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "kernel matrix"
ZZcuspidal_basis=left_kernel_matrix*ZZbasis
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "ZZkernel matrix"
assert ZZcuspidal_basis.change_ring(QQ).echelon_form()==self.S.basis_matrix() , "the calculated integral basis does not span the right QQ vector space" # a little sanity check. This shows that the colums of ZZcuspidal_basis really span the right QQ vectorspace
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "check"
#finally create the sub-module, we delibarately do this as a QQ vector space with custom basis, because this is faster then dooing the calculations over ZZ since sage will then use a slow hermite normal form algorithm.
ambient_module=VectorSpace(QQ,ZZcuspidal_basis.ncols())
int_struct = ambient_module.submodule_with_basis(ZZcuspidal_basis.rows())
if self.verbose: print "time and mem", cputime(tm), get_memory_usage(mem), "finnished"
return int_struct
def __init__(self, p, congruence_type=1, sign=1, algorithm="custom", verbose=False, dump_dir=None):
"""
Create a Kamienny criterion object.
INPUT:
- `p` -- prime -- verify that there is no order p torsion
over a degree `d` field
- `sign` -- 1 (default),-1 or 0 -- the sign of the modular symbols space to use
- ``algorithm`` -- "default" or "custom" whether to use a custom (faster)
integral structure algorithm or to use the sage builtin algortihm
- ``verbose`` -- bool; whether to print extra stuff while
running.
EXAMPLES::
sage: from mdsage import *
sage: C = KamiennyCriterion(29, algorithm="custom", verbose=False); C
Kamienny's Criterion for p=29
sage: C.use_custom_algorithm
True
sage: C.p
29
sage: C.verbose
False
"""
self.verbose = verbose
self.dump_dir = dump_dir
if self.verbose: tm = cputime(); mem = get_memory_usage(); print("init")
assert congruence_type == 0 or congruence_type == 1
self.congruence_type=congruence_type
try:
p = ZZ(p)
if congruence_type==0:
self.congruence_group = Gamma0(p)
if congruence_type==1:
self.congruence_group = GammaH(p,[-1])
except TypeError:
self.congruence_group = GammaH(p.level(),[-1]+p._generators_for_H())
self.congruence_type = ("H",self.congruence_group._list_of_elements_in_H())
self.p = self.congruence_group.level()
self.algorithm=algorithm
self.sign=sign
self.M = ModularSymbols(self.congruence_group, sign=sign)
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "modsym")
self.S = self.M.cuspidal_submodule()
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "cuspsub")
self.use_custom_algorithm = False
if algorithm=="custom":
self.use_custom_algorithm = True
if self.use_custom_algorithm:
int_struct = self.integral_cuspidal_subspace()
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "custom int_struct")
else:
int_struct = self.S.integral_structure()
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "sage int_struct")
self.S_integral = int_struct
v = VectorSpace(GF(2), self.S.dimension()).random_element()
self.v=v
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "rand_vect")
if dump_dir:
v.dump(dump_dir+"/vector%s_%s" % (p,congruence_type))
if self.verbose: print("time and mem", cputime(tm), get_memory_usage(mem), "dump")