Update docs to reflect removal of Exact/Inexact
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@ -8,9 +8,8 @@
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The :mod:`numbers` module (:pep:`3141`) defines a hierarchy of numeric abstract
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base classes which progressively define more operations. These concepts also
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provide a way to distinguish exact from inexact types. None of the types defined
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in this module can be instantiated.
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base classes which progressively define more operations. None of the types
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defined in this module can be instantiated.
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.. class:: Number
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@ -19,27 +18,6 @@ in this module can be instantiated.
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*x* is a number, without caring what kind, use ``isinstance(x, Number)``.
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Exact and inexact operations
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----------------------------
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.. class:: Exact
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Subclasses of this type have exact operations.
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As long as the result of a homogenous operation is of the same type, you can
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assume that it was computed exactly, and there are no round-off errors. Laws
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like commutativity and associativity hold.
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.. class:: Inexact
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Subclasses of this type have inexact operations.
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Given X, an instance of :class:`Inexact`, it is possible that ``(X + -X) + 3
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== 3``, but ``X + (-X + 3) == 0``. The exact form this error takes will vary
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by type, but it's generally unsafe to compare this type for equality.
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The numeric tower
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-----------------
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@ -79,7 +57,7 @@ The numeric tower
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.. class:: Rational
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Subtypes both :class:`Real` and :class:`Exact`, and adds
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Subtypes :class:`Real` and adds
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:attr:`Rational.numerator` and :attr:`Rational.denominator` properties, which
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should be in lowest terms. With these, it provides a default for
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:func:`float`.
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