本文整理汇总了Python中sage.rings.all.Integer.factorial方法的典型用法代码示例。如果您正苦于以下问题：Python Integer.factorial方法的具体用法？Python Integer.factorial怎么用？Python Integer.factorial使用的例子？那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类sage.rings.all.Integer的用法示例。
在下文中一共展示了Integer.factorial方法的1个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的Python代码示例。
示例1: an_numerical
# 需要导入模块: from sage.rings.all import Integer [as 别名]
# 或者: from sage.rings.all.Integer import factorial [as 别名]
def an_numerical(self, prec = None,
use_database=True, proof=None):
r"""
Return the numerical analytic order of `Sha`, which is
a floating point number in all cases.
INPUT:
- ``prec`` - integer (default: 53) bits precision -- used
for the L-series computation, period, regulator, etc.
- ``use_database`` - whether the rank and generators should
be looked up in the database if possible. Default is ``True``
- ``proof`` - bool or ``None`` (default: ``None``, see proof.[tab] or
sage.structure.proof) proof option passed
onto regulator and rank computation.
.. note::
See also the :meth:`an` command, which will return a
provably correct integer when the rank is 0 or 1.
.. WARNING::
If the curve's generators are not known, computing
them may be very time-consuming. Also, computation of the
L-series derivative will be time-consuming for large rank and
large conductor, and the computation time for this may
increase substantially at greater precision. However, use of
very low precision less than about 10 can cause the underlying
PARI library functions to fail.
EXAMPLES::
sage: EllipticCurve('11a').sha().an_numerical()
1.00000000000000
sage: EllipticCurve('37a').sha().an_numerical()
1.00000000000000
sage: EllipticCurve('389a').sha().an_numerical()
1.00000000000000
sage: EllipticCurve('66b3').sha().an_numerical()
4.00000000000000
sage: EllipticCurve('5077a').sha().an_numerical()
1.00000000000000
A rank 4 curve::
sage: EllipticCurve([1, -1, 0, -79, 289]).sha().an_numerical() # long time (3s on sage.math, 2011)
1.00000000000000
A rank 5 curve::
sage: EllipticCurve([0, 0, 1, -79, 342]).sha().an_numerical(prec=10, proof=False) # long time (22s on sage.math, 2011)
1.0
See :trac:`1115`::
sage: sha=EllipticCurve('37a1').sha()
sage: [sha.an_numerical(prec) for prec in xrange(40,100,10)] # long time (3s on sage.math, 2013)
[1.0000000000,
1.0000000000000,
1.0000000000000000,
1.0000000000000000000,
1.0000000000000000000000,
1.0000000000000000000000000]
"""
if prec is None:
prec = RealField().precision()
RR = RealField(prec)
prec2 = prec+2
RR2 = RealField(prec2)
try:
an = self.__an_numerical
if an.parent().precision() >= prec:
return RR(an)
else: # cached precision too low
pass
except AttributeError:
pass
# it's critical to switch to the minimal model.
E = self.Emin
r = Integer(E.rank(use_database=use_database, proof=proof))
L = E.lseries().dokchitser(prec=prec2)
Lr= RR2(L.derivative(1,r)) # L.derivative() returns a Complex
Om = RR2(E.period_lattice().omega(prec2))
Reg = E.regulator(use_database=use_database, proof=proof, precision=prec2)
T = E.torsion_order()
cp = E.tamagawa_product()
Sha = RR((Lr*T*T)/(r.factorial()*Om*cp*Reg))
self.__an_numerical = Sha
return Sha