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svn+ssh://pythondev@svn.python.org/python/trunk ........ r60735 | raymond.hettinger | 2008-02-11 23:53:01 +0100 (Mon, 11 Feb 2008) | 1 line Add notes on how decimal fits into the model. ........ r60737 | raymond.hettinger | 2008-02-12 00:34:56 +0100 (Tue, 12 Feb 2008) | 1 line Fix markup ........ r60738 | raymond.hettinger | 2008-02-12 00:38:00 +0100 (Tue, 12 Feb 2008) | 1 line Backport ABC docs ........ r60739 | raymond.hettinger | 2008-02-12 01:15:32 +0100 (Tue, 12 Feb 2008) | 1 line Restore fractions.rst to the document tree. ........ r60740 | raymond.hettinger | 2008-02-12 01:48:20 +0100 (Tue, 12 Feb 2008) | 1 line Fix typo in comments ........ r60741 | raymond.hettinger | 2008-02-12 02:18:03 +0100 (Tue, 12 Feb 2008) | 1 line Bring decimal a bit closer to the spec for Reals. ........ r60743 | martin.v.loewis | 2008-02-12 14:47:26 +0100 (Tue, 12 Feb 2008) | 2 lines Patch #1736: Fix file name handling of _msi.FCICreate. ........ r60745 | kurt.kaiser | 2008-02-12 16:45:50 +0100 (Tue, 12 Feb 2008) | 2 lines what??! Correct r60225. ........ r60747 | martin.v.loewis | 2008-02-12 19:47:34 +0100 (Tue, 12 Feb 2008) | 4 lines Patch #1966: Break infinite loop in httplib when the servers implements the chunked encoding incorrectly. Will backport to 2.5. ........ r60749 | raymond.hettinger | 2008-02-12 20:05:36 +0100 (Tue, 12 Feb 2008) | 1 line dict.copy() rises from the ashes. Revert r60687. ........
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:mod:`fractions` --- Rational numbers
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=====================================
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.. module:: fractions
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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:`fractions` module defines an immutable, infinite-precision
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Rational number class.
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.. class:: Fraction(numerator=0, denominator=1)
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Fraction(other_fraction)
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Fraction(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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``Fraction`` 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_fraction* is an instance of
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:class:`numbers.Fraction` 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:: Fraction.from_float(flt)
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This classmethod constructs a :class:`Fraction` representing the
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exact value of *flt*, which must be a :class:`float`. Beware that
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``Fraction.from_float(0.3)`` is not the same value as ``Rational(3,
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10)``
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.. method:: Fraction.from_decimal(dec)
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This classmethod constructs a :class:`Fraction` 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:: Fraction.__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:: Fraction.__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:: Fraction.__round__()
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Fraction.__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 ``Fraction(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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