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svn+ssh://pythondev@svn.python.org/python/trunk ........ r60054 | christian.heimes | 2008-01-18 20:12:56 +0100 (Fri, 18 Jan 2008) | 1 line Silence Coverity false alerts with CIDs #172, #183, #184 ........ r60057 | guido.van.rossum | 2008-01-18 21:56:30 +0100 (Fri, 18 Jan 2008) | 3 lines Fix an edge case whereby the __del__() method of a classic class could create a new weakref to the object. ........ r60058 | raymond.hettinger | 2008-01-18 22:14:58 +0100 (Fri, 18 Jan 2008) | 1 line Better variable name in an example. ........ r60063 | guido.van.rossum | 2008-01-19 00:05:40 +0100 (Sat, 19 Jan 2008) | 3 lines This got fixed for classic classes in r60057, and backported to 2.5.2 in 60056. ........ r60068 | jeffrey.yasskin | 2008-01-19 10:56:06 +0100 (Sat, 19 Jan 2008) | 4 lines Several tweaks: add construction from strings and .from_decimal(), change __init__ to __new__ to enforce immutability, and remove "rational." from repr and the parens from str. ........ r60069 | georg.brandl | 2008-01-19 11:11:27 +0100 (Sat, 19 Jan 2008) | 2 lines Fix markup. ........ r60070 | georg.brandl | 2008-01-19 11:16:09 +0100 (Sat, 19 Jan 2008) | 3 lines Amend curses docs by info how to write non-ascii characters. Thanks to Jeroen Ruigrok van der Werven. ........ r60071 | georg.brandl | 2008-01-19 11:18:07 +0100 (Sat, 19 Jan 2008) | 2 lines Indentation normalization. ........ r60073 | facundo.batista | 2008-01-19 13:32:27 +0100 (Sat, 19 Jan 2008) | 5 lines Fix issue #1822: MIMEMultipart.is_multipart() behaves correctly for a just-created (and empty) instance. Added tests for this. Thanks Jonathan Share. ........ r60074 | andrew.kuchling | 2008-01-19 14:33:20 +0100 (Sat, 19 Jan 2008) | 1 line Polish sentence ........ r60075 | christian.heimes | 2008-01-19 14:46:06 +0100 (Sat, 19 Jan 2008) | 1 line Added unit test to verify that threading.local doesn't cause ref leaks. It seems that the thread local storage always keeps the storage of the last stopped thread alive. Can anybody comment on it, please? ........ r60076 | christian.heimes | 2008-01-19 16:06:09 +0100 (Sat, 19 Jan 2008) | 1 line Update for threading.local test. ........ r60077 | andrew.kuchling | 2008-01-19 16:16:37 +0100 (Sat, 19 Jan 2008) | 1 line Polish sentence ........ r60078 | georg.brandl | 2008-01-19 16:22:16 +0100 (Sat, 19 Jan 2008) | 2 lines Fix typos. ........
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:mod:`rational` --- Rational numbers
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====================================
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.. module:: rational
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:synopsis: Rational numbers.
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.. moduleauthor:: Jeffrey Yasskin <jyasskin at gmail.com>
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.. sectionauthor:: Jeffrey Yasskin <jyasskin at gmail.com>
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.. versionadded:: 2.6
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The :mod:`rational` module defines an immutable, infinite-precision
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Rational number class.
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.. class:: Rational(numerator=0, denominator=1)
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Rational(other_rational)
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Rational(string)
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The first version requires that *numerator* and *denominator* are
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instances of :class:`numbers.Integral` and returns a new
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``Rational`` representing ``numerator/denominator``. If
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*denominator* is :const:`0`, raises a :exc:`ZeroDivisionError`. The
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second version requires that *other_rational* is an instance of
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:class:`numbers.Rational` and returns an instance of
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:class:`Rational` with the same value. The third version expects a
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string of the form ``[-+]?[0-9]+(/[0-9]+)?``, optionally surrounded
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by spaces.
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Implements all of the methods and operations from
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:class:`numbers.Rational` and is immutable and hashable.
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.. method:: Rational.from_float(flt)
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This classmethod constructs a :class:`Rational` representing the
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exact value of *flt*, which must be a :class:`float`. Beware that
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``Rational.from_float(0.3)`` is not the same value as ``Rational(3,
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10)``
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.. method:: Rational.from_decimal(dec)
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This classmethod constructs a :class:`Rational` representing the
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exact value of *dec*, which must be a
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:class:`decimal.Decimal`.
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.. method:: Rational.__floor__()
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Returns the greatest :class:`int` ``<= self``. Will be accessible
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through :func:`math.floor` in Py3k.
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.. method:: Rational.__ceil__()
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Returns the least :class:`int` ``>= self``. Will be accessible
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through :func:`math.ceil` in Py3k.
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.. method:: Rational.__round__()
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Rational.__round__(ndigits)
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The first version returns the nearest :class:`int` to ``self``,
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rounding half to even. The second version rounds ``self`` to the
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nearest multiple of ``Rational(1, 10**ndigits)`` (logically, if
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``ndigits`` is negative), again rounding half toward even. Will be
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accessible through :func:`round` in Py3k.
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.. seealso::
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Module :mod:`numbers`
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The abstract base classes making up the numeric tower.
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