50 lines
1.6 KiB
Plaintext
50 lines
1.6 KiB
Plaintext
[/
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Copyright 2011 - 2020 John Maddock.
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Copyright 2013 - 2019 Paul A. Bristow.
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Copyright 2013 Christopher Kormanyos.
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Distributed under the Boost Software License, Version 1.0.
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(See accompanying file LICENSE_1_0.txt or copy at
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http://www.boost.org/LICENSE_1_0.txt).
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]
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[section:cpp_rational cpp_rational]
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`#include <boost/multiprecision/cpp_int.hpp>`
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namespace boost{ namespace multiprecision{
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typedef rational_adaptor<cpp_int_backend<> > cpp_rational_backend;
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typedef number<cpp_rational_backend> cpp_rational;
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}} // namespaces
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The `cpp_rational_backend` type is used via the typedef `boost::multiprecision::cpp_rational`. It provides
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a rational number type that is a drop-in replacement for the native C++ number types, but with unlimited precision.
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As well as the usual conversions from arithmetic and string types, instances of `cpp_rational` are copy constructible
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and assignable from type `cpp_int`.
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There is also a two argument constructor that accepts a numerator and denominator: both of type `cpp_int`.
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There are also non-member functions:
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cpp_int numerator(const cpp_rational&);
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cpp_int denominator(const cpp_rational&);
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which return the numerator and denominator of the number.
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Things you should know when using this type:
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* Default constructed `cpp_rational`s have the value zero.
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* Division by zero results in a `std::overflow_error` being thrown.
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* Conversion from a string results in a `std::runtime_error` being thrown if the string can not be
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interpreted as a valid rational number.
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[h5 Example:]
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[cpp_rational_eg]
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[endsect] [/section:rational Rational Number Types]
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