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""" `p`-Adic Base Leaves
Implementations of `\mathbb{Z}_p` and `\mathbb{Q}_p`
AUTHORS:
- David Roe - Genya Zaytman: documentation - David Harvey: doctests - William Stein: doctest updates
EXAMPLES:
`p`-Adic rings and fields are examples of inexact structures, as the reals are. That means that elements cannot generally be stored exactly: to do so would take an infinite amount of storage. Instead, we store an approximation to the elements with varying precision.
There are two types of precision for a `p`-adic element. The first is relative precision, which gives the number of known `p`-adic digits::
sage: R = Qp(5, 20, 'capped-rel', 'series'); a = R(675); a 2*5^2 + 5^4 + O(5^22) sage: a.precision_relative() 20
The second type of precision is absolute precision, which gives the power of `p` that this element is stored modulo::
sage: a.precision_absolute() 22
The number of times that `p` divides the element is called the valuation, and can be accessed with the functions ``valuation()`` and ``ordp()``:
sage: a.valuation() 2
The following relationship holds:
``self.valuation() + self.precision_relative() == self.precision_absolute().``
sage: a.valuation() + a.precision_relative() == a.precision_absolute() True
In the capped relative case, the relative precision of an element is restricted to be at most a certain value, specified at the creation of the field. Individual elements also store their own precision, so the effect of various arithmetic operations on precision is tracked. When you cast an exact element into a capped relative field, it truncates it to the precision cap of the field.::
sage: R = Qp(5, 5); a = R(4006); a 1 + 5 + 2*5^3 + 5^4 + O(5^5) sage: b = R(17/3); b 4 + 2*5 + 3*5^2 + 5^3 + 3*5^4 + O(5^5) sage: c = R(4025); c 5^2 + 2*5^3 + 5^4 + 5^5 + O(5^7) sage: a + b 4*5 + 3*5^2 + 3*5^3 + 4*5^4 + O(5^5) sage: a + b + c 4*5 + 4*5^2 + 5^4 + O(5^5)
::
sage: R = Zp(5, 5, 'capped-rel', 'series'); a = R(4006); a 1 + 5 + 2*5^3 + 5^4 + O(5^5) sage: b = R(17/3); b 4 + 2*5 + 3*5^2 + 5^3 + 3*5^4 + O(5^5) sage: c = R(4025); c 5^2 + 2*5^3 + 5^4 + 5^5 + O(5^7) sage: a + b 4*5 + 3*5^2 + 3*5^3 + 4*5^4 + O(5^5) sage: a + b + c 4*5 + 4*5^2 + 5^4 + O(5^5)
In the capped absolute type, instead of having a cap on the relative precision of an element there is instead a cap on the absolute precision. Elements still store their own precisions, and as with the capped relative case, exact elements are truncated when cast into the ring.::
sage: R = ZpCA(5, 5); a = R(4005); a 5 + 2*5^3 + 5^4 + O(5^5) sage: b = R(4025); b 5^2 + 2*5^3 + 5^4 + O(5^5) sage: a * b 5^3 + 2*5^4 + O(5^5) sage: (a * b) // 5^3 1 + 2*5 + O(5^2) sage: type((a * b) // 5^3) <type 'sage.rings.padics.padic_capped_absolute_element.pAdicCappedAbsoluteElement'> sage: (a * b) / 5^3 1 + 2*5 + O(5^2) sage: type((a * b) / 5^3) <type 'sage.rings.padics.padic_capped_relative_element.pAdicCappedRelativeElement'>
The fixed modulus type is the leanest of the p-adic rings: it is basically just a wrapper around `\mathbb{Z} / p^n \mathbb{Z}` providing a unified interface with the rest of the `p`-adics. This is the type you should use if your primary interest is in speed (though it's not all that much faster than other `p`-adic types). It does not track precision of elements.::
sage: R = ZpFM(5, 5); a = R(4005); a 5 + 2*5^3 + 5^4 + O(5^5) sage: a // 5 1 + 2*5^2 + 5^3 + O(5^5)
`p`-Adic rings and fields should be created using the creation functions ``Zp`` and ``Qp`` as above. This will ensure that there is only one instance of `\mathbb{Z}_p` and `\mathbb{Q}_p` of a given type, `p`, print mode and precision. It also saves typing very long class names.::
sage: Qp(17,10) 17-adic Field with capped relative precision 10 sage: R = Qp(7, prec = 20, print_mode = 'val-unit'); S = Qp(7, prec = 20, print_mode = 'val-unit'); R is S True sage: Qp(2) 2-adic Field with capped relative precision 20
Once one has a `p`-Adic ring or field, one can cast elements into it in the standard way. Integers, ints, longs, Rationals, other `p`-Adic types, pari `p`-adics and elements of `\mathbb{Z} / p^n \mathbb{Z}` can all be cast into a `p`-Adic field.::
sage: R = Qp(5, 5, 'capped-rel','series'); a = R(16); a 1 + 3*5 + O(5^5) sage: b = R(23/15); b 5^-1 + 3 + 3*5 + 5^2 + 3*5^3 + O(5^4) sage: S = Zp(5, 5, 'fixed-mod','val-unit'); c = S(Mod(75,125)); c 5^2 * 3 + O(5^5) sage: R(c) 3*5^2 + O(5^5)
In the previous example, since fixed-mod elements don't keep track of their precision, we assume that it has the full precision of the ring. This is why you have to cast manually here.
While you can cast explicitly as above, the chains of automatic coercion are more restricted. As always in Sage, the following arrows are transitive and the diagram is commutative.::
int -> long -> Integer -> Zp capped-rel -> Zp capped_abs -> IntegerMod Integer -> Zp fixed-mod -> IntegerMod Integer -> Zp capped-abs -> Qp capped-rel
In addition, there are arrows within each type. For capped relative and capped absolute rings and fields, these arrows go from lower precision cap to higher precision cap. This works since elements track their own precision: choosing the parent with higher precision cap means that precision is less likely to be truncated unnecessarily. For fixed modulus parents, the arrow goes from higher precision cap to lower. The fact that elements do not track precision necessitates this choice in order to not produce incorrect results.
TESTS::
sage: R = Qp(5, 15, print_mode='bars', print_sep='&') sage: repr(R(2777))[3:] '0&0&0&0&0&0&0&0&0&0&4&2&1&0&2' sage: TestSuite(R).run()
sage: R = Zp(5, 15, print_mode='bars', print_sep='&') sage: repr(R(2777))[3:] '0&0&0&0&0&0&0&0&0&0&4&2&1&0&2' sage: TestSuite(R).run()
sage: R = ZpCA(5, 15, print_mode='bars', print_sep='&') sage: repr(R(2777))[3:] '0&0&0&0&0&0&0&0&0&0&4&2&1&0&2' sage: TestSuite(R).run()
""" from __future__ import absolute_import
#***************************************************************************** # Copyright (C) 2008 David Roe <roed.math@gmail.com> # William Stein <wstein@gmail.com> # # Distributed under the terms of the GNU General Public License (GPL) # as published by the Free Software Foundation; either version 2 of # the License, or (at your option) any later version. # # http://www.gnu.org/licenses/ #***************************************************************************** from sage.structure.richcmp import op_LE
from .generic_nodes import pAdicFieldBaseGeneric, \ pAdicCappedRelativeFieldGeneric, \ pAdicRingBaseGeneric, \ pAdicCappedRelativeRingGeneric, \ pAdicFixedModRingGeneric, \ pAdicCappedAbsoluteRingGeneric, \ pAdicFloatingPointRingGeneric, \ pAdicFloatingPointFieldGeneric, \ pAdicGeneric, \ pAdicLatticeGeneric from .padic_capped_relative_element import pAdicCappedRelativeElement from .padic_capped_absolute_element import pAdicCappedAbsoluteElement from .padic_fixed_mod_element import pAdicFixedModElement from .padic_floating_point_element import pAdicFloatingPointElement
from sage.rings.integer_ring import ZZ from sage.rings.rational_field import QQ
class pAdicRingCappedRelative(pAdicRingBaseGeneric, pAdicCappedRelativeRingGeneric): r""" An implementation of the `p`-adic integers with capped relative precision. """ def __init__(self, p, prec, print_mode, names): """ Initialization.
INPUT:
- ``p`` -- prime - ``prec`` -- precision cap - ``print_mode`` -- dictionary with print options. - ``names`` -- how to print the prime.
EXAMPLES::
sage: R = ZpCR(next_prime(10^60)) #indirect doctest sage: type(R) <class 'sage.rings.padics.padic_base_leaves.pAdicRingCappedRelative_with_category'>
TESTS::
sage: R = ZpCR(2) sage: TestSuite(R).run() sage: TestSuite(R).run(elements = [R.random_element() for i in range(2^10)], max_runs = 2^12, skip='_test_metric') # long time sage: R._test_metric(elements = [R.random_element() for i in range(2^3)]) # long time
sage: R = ZpCR(3, 1) sage: TestSuite(R).run(elements = [R.random_element() for i in range(3^3)])
sage: R = ZpCR(3, 2) sage: TestSuite(R).run(elements = [R.random_element() for i in range(3^6)], skip='_test_metric') # long time sage: R._test_metric(elements = [R.random_element() for i in range(2^3)]) # long time
sage: R = ZpCR(next_prime(10^60)) sage: TestSuite(R).run(elements = [R.random_element() for i in range(2^3)], max_runs = 2^5, skip='_test_log') # long time sage: R._test_log(max_runs=2, elements=[R.random_element() for i in range(4)]) # long time """
def _coerce_map_from_(self, R): """ Return ``True`` if there is a coerce map from ``R`` to ``self``.
EXAMPLES::
sage: K = Zp(17) sage: K(1) + 1 #indirect doctest 2 + O(17^20) sage: K.has_coerce_map_from(ZZ) True sage: K.has_coerce_map_from(int) True sage: K.has_coerce_map_from(QQ) False sage: K.has_coerce_map_from(RR) False sage: K.has_coerce_map_from(Qp(7)) False sage: K.has_coerce_map_from(Zp(17,40)) False sage: K.has_coerce_map_from(Zp(17,10)) True sage: K.has_coerce_map_from(ZpCA(17,40)) False """ #if isistance(R, pAdicRingLazy) and R.prime() == self.prime(): # return True self._printer.richcmp_modes(R._printer, op_LE)):
def _convert_map_from_(self, R): """ Finds conversion maps from R to this ring.
EXAMPLES::
sage: Zp(7).convert_map_from(Zmod(343)) Lifting morphism: From: Ring of integers modulo 343 To: 7-adic Ring with capped relative precision 20 """
class pAdicRingCappedAbsolute(pAdicRingBaseGeneric, pAdicCappedAbsoluteRingGeneric): r""" An implementation of the `p`-adic integers with capped absolute precision. """ def __init__(self, p, prec, print_mode, names): """ Initialization.
INPUT:
- ``p`` -- prime - ``prec`` -- precision cap - ``print_mode`` -- dictionary with print options. - ``names`` -- how to print the prime.
EXAMPLES::
sage: R = ZpCA(next_prime(10^60)) #indirect doctest sage: type(R) <class 'sage.rings.padics.padic_base_leaves.pAdicRingCappedAbsolute_with_category'>
TESTS::
sage: R = ZpCA(2) sage: TestSuite(R).run() sage: TestSuite(R).run(elements = [R.random_element() for i in range(2^10)], max_runs = 2^12, skip='_test_metric') # long time sage: R._test_metric(elements = [R.random_element() for i in range(2^3)]) # long time
sage: R = ZpCA(3, 1) sage: TestSuite(R).run(elements = [R.random_element() for i in range(3^3)])
sage: R = ZpCA(3, 2) sage: TestSuite(R).run(elements = [R.random_element() for i in range(3^6)], skip='_test_metric') # long time sage: R._test_metric(elements = [R.random_element() for i in range(2^3)]) # long time
sage: R = ZpCA(next_prime(10^60)) sage: TestSuite(R).run(elements = [R.random_element() for i in range(2^3)], max_runs = 2^5, skip='_test_log') # long time sage: R._test_log(max_runs=2, elements=[R.random_element() for i in range(4)]) """
def _coerce_map_from_(self, R): """ Returns ``True`` if there is a coerce map from ``R`` to ``self``.
EXAMPLES::
sage: K = ZpCA(17) sage: K(1) + 1 #indirect doctest 2 + O(17^20) sage: K.has_coerce_map_from(ZZ) True sage: K.has_coerce_map_from(int) True sage: K.has_coerce_map_from(QQ) False sage: K.has_coerce_map_from(RR) False sage: K.has_coerce_map_from(Qp(7)) False sage: K.has_coerce_map_from(ZpCA(17,40)) False sage: K.has_coerce_map_from(ZpCA(17,10)) True sage: K.has_coerce_map_from(Zp(17,40)) True """ #if isistance(R, pAdicRingLazy) and R.prime() == self.prime(): # return True self._printer.richcmp_modes(R._printer, op_LE)): return True
def _convert_map_from_(self, R): """ Finds conversion maps from R to this ring.
EXAMPLES::
sage: ZpCA(7).convert_map_from(Zmod(343)) Lifting morphism: From: Ring of integers modulo 343 To: 7-adic Ring with capped absolute precision 20 """
class pAdicRingFloatingPoint(pAdicRingBaseGeneric, pAdicFloatingPointRingGeneric): r""" An implementation of the `p`-adic integers with floating point precision. """ def __init__(self, p, prec, print_mode, names): """ Initialization.
INPUT:
- ``p`` -- prime - ``prec`` -- precision cap - ``print_mode`` -- dictionary with print options. - ``names`` -- how to print the prime.
EXAMPLES::
sage: R = ZpFP(next_prime(10^60)) #indirect doctest sage: type(R) <class 'sage.rings.padics.padic_base_leaves.pAdicRingFloatingPoint_with_category'>
TESTS::
sage: R = ZpFP(2) sage: TestSuite(R).run() sage: TestSuite(R).run(elements = [R.random_element() for i in range(2^10)], max_runs = 2^12, skip='_test_metric') # long time sage: R._test_metric(elements = [R.random_element() for i in range(2^3)]) # long time
sage: R = ZpFP(3, 1) sage: TestSuite(R).run(elements = [R.random_element() for i in range(3^3)])
sage: R = ZpFP(3, 2) sage: TestSuite(R).run(elements = [R.random_element() for i in range(3^6)], skip='_test_metric') # long time sage: R._test_metric(elements = [R.random_element() for i in range(2^3)]) # long time
sage: R = ZpFP(next_prime(10^60)) sage: TestSuite(R).run(elements = [R.random_element() for i in range(2^3)], max_runs = 2^5, skip='_test_log') # long time sage: R._test_log(max_runs=2, elements=[R.random_element() for i in range(4)]) """
def _coerce_map_from_(self, R): """ Returns ``True`` if there is a coerce map from ``R`` to ``self``.
EXAMPLES::
sage: K = ZpFP(17) sage: K(1) + 1 #indirect doctest 2 sage: K.has_coerce_map_from(ZZ) True sage: K.has_coerce_map_from(int) True sage: K.has_coerce_map_from(QQ) False sage: K.has_coerce_map_from(RR) False sage: K.has_coerce_map_from(Qp(7)) False sage: K.has_coerce_map_from(Zp(17,40)) False sage: K.has_coerce_map_from(Zp(17,10)) False sage: K.has_coerce_map_from(ZpCA(17,40)) False """ if R.precision_cap() > self.precision_cap(): return True elif R.precision_cap() == self.precision_cap() and self._printer.richcmp_modes(R._printer, op_LE): return True
def _convert_map_from_(self, R): """ Finds conversion maps from R to this ring.
EXAMPLES::
sage: ZpFP(7).convert_map_from(Zmod(343)) Lifting morphism: From: Ring of integers modulo 343 To: 7-adic Ring with floating precision 20 """
class pAdicRingFixedMod(pAdicRingBaseGeneric, pAdicFixedModRingGeneric): r""" An implementation of the `p`-adic integers using fixed modulus. """ def __init__(self, p, prec, print_mode, names): """ Initialization
INPUT:
- ``p`` -- prime - ``prec`` -- precision cap - ``print_mode`` -- dictionary with print options. - ``names`` -- how to print the prime.
EXAMPLES::
sage: R = ZpFM(next_prime(10^60)) #indirect doctest sage: type(R) <class 'sage.rings.padics.padic_base_leaves.pAdicRingFixedMod_with_category'>
TESTS::
sage: R = ZpFM(2) sage: TestSuite(R).run() sage: TestSuite(R).run(elements = [R.random_element() for i in range(2^10)], max_runs = 2^12, skip='_test_metric') # long time sage: R._test_metric(elements = [R.random_element() for i in range(2^3)]) # long time
sage: R = ZpFM(3, 1) sage: TestSuite(R).run(elements = [R.random_element() for i in range(3^3)])
sage: R = ZpFM(3, 2) sage: TestSuite(R).run(elements = [R.random_element() for i in range(3^6)], skip='_test_metric') # long time sage: R._test_metric(elements = [R.random_element() for i in range(2^3)]) # long time
sage: R = ZpFM(next_prime(10^60)) sage: TestSuite(R).run(skip='_test_log') sage: TestSuite(R).run(elements = [R.random_element() for i in range(2^4)], max_runs = 2^6, skip='_test_log') # long time sage: R._test_log(max_runs=2, elements=[R.random_element() for i in range(4)])
Fraction fields work after :trac:`23510`::
sage: R = ZpFM(5) sage: K = R.fraction_field(); K 5-adic Field with floating precision 20 sage: K(R(90)) 3*5 + 3*5^2 """
def _coerce_map_from_(self, R): """ Returns ``True`` if there is a coerce map from ``R`` to ``self``.
EXAMPLES::
sage: K = ZpFM(17) sage: K(1) + 1 #indirect doctest 2 + O(17^20) sage: K.has_coerce_map_from(ZZ) True sage: K.has_coerce_map_from(int) True sage: K.has_coerce_map_from(QQ) False sage: K.has_coerce_map_from(RR) False sage: K.has_coerce_map_from(Zp(7)) False sage: K.has_coerce_map_from(ZpFM(17,40)) True sage: K.has_coerce_map_from(ZpFM(17,10)) False sage: K.has_coerce_map_from(Zp(17,40)) False """ #if isistance(R, pAdicRingLazy) and R.prime() == self.prime(): # return True self._printer.richcmp_modes(R._printer, op_LE)): return True
def _convert_map_from_(self, R): """ Finds conversion maps from R to this ring.
EXAMPLES::
sage: ZpFM(7).convert_map_from(Zmod(343)) Lifting morphism: From: Ring of integers modulo 343 To: 7-adic Ring of fixed modulus 7^20 """
class pAdicFieldCappedRelative(pAdicFieldBaseGeneric, pAdicCappedRelativeFieldGeneric): r""" An implementation of `p`-adic fields with capped relative precision.
EXAMPLES::
sage: K = Qp(17, 1000000) #indirect doctest sage: K = Qp(101) #indirect doctest
"""
def __init__(self, p, prec, print_mode, names): """ Initialization.
INPUT:
- ``p`` -- prime - ``prec`` -- precision cap - ``print_mode`` -- dictionary with print options. - ``names`` -- how to print the prime.
EXAMPLES::
sage: K = Qp(next_prime(10^60)) # indirect doctest sage: type(K) <class 'sage.rings.padics.padic_base_leaves.pAdicFieldCappedRelative_with_category'>
TESTS::
sage: R = Qp(2) sage: TestSuite(R).run() sage: TestSuite(R).run(elements = [R.random_element() for i in range(2^10)], max_runs = 2^12, skip='_test_metric') # long time sage: R._test_metric(elements = [R.random_element() for i in range(2^3)]) # long time
sage: R = Qp(3, 1) sage: TestSuite(R).run(elements = [R.random_element() for i in range(3^6)], skip='_test_metric') # long time sage: R._test_metric(elements = [R.random_element() for i in range(2^3)]) # long time
sage: R = Qp(3, 2) sage: TestSuite(R).run(elements=[R.random_element() for i in range(3^9)], skip="_test_metric") # long time sage: R._test_metric(elements=[R.random_element() for i in range(3^3)])
sage: R = Qp(next_prime(10^60)) sage: TestSuite(R).run(skip='_test_log') sage: TestSuite(R).run(elements = [R.random_element() for i in range(2^3)], max_runs = 2^5, skip='_test_log') # long time sage: R._test_log(max_runs=2, elements=[R.random_element() for i in range(4)]) """
def _coerce_map_from_(self, R): """ Returns ``True`` if there is a coerce map from ``R`` to ``self``.
EXAMPLES::
sage: K = Qp(17) sage: K(1) + 1 #indirect doctest 2 + O(17^20) sage: K.has_coerce_map_from(ZZ) True sage: K.has_coerce_map_from(int) True sage: K.has_coerce_map_from(QQ) True sage: K.has_coerce_map_from(RR) False sage: K.has_coerce_map_from(Qp(7)) False sage: K.has_coerce_map_from(Qp(17,40)) False sage: K.has_coerce_map_from(Qp(17,10)) True sage: K.has_coerce_map_from(Zp(17,40)) True
""" #if isinstance(R, pAdicRingLazy) or isinstance(R, pAdicFieldLazy) and R.prime() == self.prime(): # return True self._printer.richcmp_modes(R._printer, op_LE)):
def _convert_map_from_(self, R): """ Finds conversion maps from R to this ring.
EXAMPLES::
sage: Qp(7).convert_map_from(Zmod(343)) Lifting morphism: From: Ring of integers modulo 343 To: 7-adic Field with capped relative precision 20 """
def random_element(self, algorithm='default'): r""" Returns a random element of ``self``, optionally using the ``algorithm`` argument to decide how it generates the element. Algorithms currently implemented:
- default: Choose an integer `k` using the standard distribution on the integers. Then choose an integer `a` uniformly in the range `0 \le a < p^N` where `N` is the precision cap of ``self``. Return ``self(p^k * a, absprec = k + self.precision_cap())``.
EXAMPLES::
sage: Qp(17,6).random_element() 15*17^-8 + 10*17^-7 + 3*17^-6 + 2*17^-5 + 11*17^-4 + 6*17^-3 + O(17^-2) """ else: raise NotImplementedError("Don't know %s algorithm"%algorithm)
class pAdicFieldFloatingPoint(pAdicFieldBaseGeneric, pAdicFloatingPointFieldGeneric): r""" An implementation of the `p`-adic rationals with floating point precision. """ def __init__(self, p, prec, print_mode, names): """ Initialization.
INPUT:
- ``p`` -- prime - ``prec`` -- precision cap - ``print_mode`` -- dictionary with print options. - ``names`` -- how to print the prime.
EXAMPLES::
sage: R = QpFP(next_prime(10^60)) #indirect doctest sage: type(R) <class 'sage.rings.padics.padic_base_leaves.pAdicFieldFloatingPoint_with_category'>
TESTS::
sage: R = QpFP(2) sage: TestSuite(R).run() sage: TestSuite(R).run(elements = [R.random_element() for i in range(2^10)], max_runs = 2^12, skip='_test_metric') # long time sage: R._test_metric(elements = [R.random_element() for i in range(2^3)]) # long time
sage: R = QpFP(3, 1) sage: TestSuite(R).run(elements = [R.random_element() for i in range(3^3)])
sage: R = QpFP(3, 2) sage: TestSuite(R).run(elements = [R.random_element() for i in range(3^6)], skip='_test_metric') # long time sage: R._test_metric(elements = [R.random_element() for i in range(2^3)]) # long time
sage: R = QpFP(next_prime(10^60)) sage: TestSuite(R).run(skip='_test_log') sage: TestSuite(R).run(elements = [R.random_element() for i in range(2^3)], max_runs = 2^5, skip='_test_log') # long time sage: R._test_log(max_runs=2, elements=[R.random_element() for i in range(4)]) """
def _coerce_map_from_(self, R): """ Returns ``True`` if there is a coerce map from ``R`` to ``self``.
EXAMPLES::
sage: K = QpFP(17) sage: K(1) + 1 #indirect doctest 2 sage: K.has_coerce_map_from(ZZ) True sage: K.has_coerce_map_from(int) True sage: K.has_coerce_map_from(QQ) True sage: K.has_coerce_map_from(RR) False sage: K.has_coerce_map_from(Qp(7)) False sage: K.has_coerce_map_from(Zp(17,40)) False sage: K.has_coerce_map_from(Qp(17,10)) False sage: K.has_coerce_map_from(ZpFP(17)) True sage: K.has_coerce_map_from(ZpCA(17,40)) False """ return True
def _convert_map_from_(self, R): """ Finds conversion maps from R to this ring.
EXAMPLES::
sage: QpFP(7).convert_map_from(Zmod(343)) Lifting morphism: From: Ring of integers modulo 343 To: 7-adic Field with floating precision 20 """
# Lattice precision ###################
class pAdicRingLattice(pAdicLatticeGeneric, pAdicRingBaseGeneric): """ An implementation of the `p`-adic integers with lattice precision.
INPUT:
- ``p`` -- prime
- ``prec`` -- precision cap, given as a pair (``relative_cap``, ``absolute_cap``)
- ``subtype`` -- either ``'cap'`` or ``'float'``
- ``print_mode`` -- dictionary with print options
- ``names`` -- how to print the prime
- ``label`` -- the label of this ring
.. SEEALSO::
:meth:`label`
EXAMPLES::
sage: R = ZpLC(next_prime(10^60)) # indirect doctest doctest:...: FutureWarning: This class/method/function is marked as experimental. It, its functionality or its interface might change without a formal deprecation. See http://trac.sagemath.org/23505 for details. sage: type(R) <class 'sage.rings.padics.padic_base_leaves.pAdicRingLattice_with_category'>
sage: R = ZpLC(2, label='init') # indirect doctest sage: R 2-adic Ring with lattice-cap precision (label: init) """ def __init__(self, p, prec, subtype, print_mode, names, label=None): """ Initialization.
TESTS:
sage: R = ZpLC(7, label='init') sage: TestSuite(R).run(skip='_test_teichmuller') """ # We need to set the subtype first, so that # pAdicRingBaseGeneric.__init__ can work else:
def _coerce_map_from_(self, R): """ Return ``True`` if there is a coerce map from ``R`` to this ring.
EXAMPLES::
sage: R = ZpLC(2) sage: R.has_coerce_map_from(ZZ) True sage: R.has_coerce_map_from(QQ) False
sage: K = R.fraction_field() sage: K.has_coerce_map_from(R) True sage: K.has_coerce_map_from(QQ) True
Note that coerce map does not exist between ``p``-adic rings with lattice precision and other ``p``-adic rings.
sage: S = Zp(2) sage: R.has_coerce_map_from(S) False sage: S.has_coerce_map_from(R) False
Similarly there is no coercion maps between ``p``-adic rings with different labels.
sage: R2 = ZpLC(2, label='coerce') sage: R.has_coerce_map_from(R2) False sage: R2.has_coerce_map_from(R) False """ return True
def random_element(self, prec=None): """ Return a random element of this ring.
INPUT:
- ``prec`` -- an integer or ``None`` (the default): the absolute precision of the generated random element
EXAMPLES::
sage: R = ZpLC(2) sage: R.random_element() # random 2^3 + 2^4 + 2^5 + 2^6 + 2^7 + 2^10 + 2^11 + 2^14 + 2^15 + 2^16 + 2^17 + 2^18 + 2^19 + 2^21 + O(2^23)
sage: R.random_element(prec=10) # random 1 + 2^3 + 2^4 + 2^7 + O(2^10) """ else: else:
class pAdicFieldLattice(pAdicLatticeGeneric, pAdicFieldBaseGeneric): """ An implementation of the `p`-adic numbers with lattice precision.
INPUT:
- ``p`` -- prime
- ``prec`` -- precision cap, given as a pair (``relative_cap``, ``absolute_cap``)
- ``subtype`` -- either ``'cap'`` or ``'float'``
- ``print_mode`` -- dictionary with print options
- ``names`` -- how to print the prime
- ``label`` -- the label of this ring
.. SEEALSO::
:meth:`label`
EXAMPLES::
sage: R = QpLC(next_prime(10^60)) # indirect doctest doctest:...: FutureWarning: This class/method/function is marked as experimental. It, its functionality or its interface might change without a formal deprecation. See http://trac.sagemath.org/23505 for details. sage: type(R) <class 'sage.rings.padics.padic_base_leaves.pAdicFieldLattice_with_category'>
sage: R = QpLC(2,label='init') # indirect doctest sage: R 2-adic Field with lattice-cap precision (label: init) """ def __init__(self, p, prec, subtype, print_mode, names, label=None): """ Initialization.
TESTS::
sage: R = ZpLC(7, label='init') sage: TestSuite(R).run(skip='_test_teichmuller') """ # We need to set the subtype first, so that # pAdicFieldBaseGeneric.__init__ can work else:
def _coerce_map_from_(self, R): """ Return ``True`` if there is a coerce map from ``R`` to this ring.
EXAMPLES::
sage: R = ZpLC(2) sage: R.has_coerce_map_from(ZZ) True sage: R.has_coerce_map_from(QQ) False
sage: K = R.fraction_field() sage: K.has_coerce_map_from(R) True sage: K.has_coerce_map_from(QQ) True
Note that coerce map does not exist between ``p``-adic fields with lattice precision and other ``p``-adic rings.
sage: L = Qp(2) sage: K.has_coerce_map_from(L) False sage: L.has_coerce_map_from(K) False
Similarly there is no coercion maps between ``p``-adic rings with different labels.
sage: K2 = QpLC(2, label='coerce') sage: K.has_coerce_map_from(K2) False sage: K2.has_coerce_map_from(K) False """
def random_element(self, prec=None, integral=False): """ Return a random element of this ring.
INPUT:
- ``prec`` -- an integer or ``None`` (the default): the absolute precision of the generated random element
- ``integral`` -- a boolean (default: ``False``); if true return an element in the ring of integers
EXAMPLES::
sage: K = QpLC(2) sage: K.random_element() # random 2^-8 + 2^-7 + 2^-6 + 2^-5 + 2^-3 + 1 + 2^2 + 2^3 + 2^5 + O(2^12) sage: K.random_element(integral=True) # random 2^3 + 2^4 + 2^5 + 2^6 + 2^7 + 2^10 + 2^11 + 2^14 + 2^15 + 2^16 + 2^17 + 2^18 + 2^19 + O(2^20)
sage: K.random_element(prec=10) # random 2^(-3) + 1 + 2 + 2^4 + 2^8 + O(2^10)
If the given precision is higher than the internal cap of the parent, then the cap is used::
sage: K.precision_cap_relative() 20 sage: K.random_element(prec=100) # random 2^5 + 2^8 + 2^11 + 2^12 + 2^14 + 2^18 + 2^20 + 2^24 + O(2^25) """ else: |