[/ Copyright 2011 - 2020 John Maddock. Copyright 2013 - 2019 Paul A. Bristow. Copyright 2013 Christopher Kormanyos. Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt). ] [section:cpp_dec_ref cpp_dec_float] namespace boost{ namespace multiprecision{ template <unsigned Digits10, class ExponentType = std::int32_t, class Allocator = void> class cpp_dec_float; typedef number<cpp_dec_float<50> > cpp_dec_float_50; typedef number<cpp_dec_float<100> > cpp_dec_float_100; }} // namespaces Class template `cpp_dec_float` fulfils all of the requirements for a [link boost_multiprecision.ref.backendconc Backend] type. Its members and non-member functions are deliberately not documented: these are considered implementation details that are subject to change. The class takes three template parameters: [variablelist [[Digits10][The number of decimal digits precision the type should support. Note that this type does not normally perform any dynamic memory allocation, and as a result the `Digits10` template argument should not be set too high or the class's size will grow unreasonably large.]] [[ExponentType][A signed integer type that represents the exponent of the number]] [[Allocator][The allocator used: defaults to type `void`, meaning all storage is within the class, and no dynamic allocation is performed, but can be set to a standard library allocator if dynamic allocation makes more sense.]] ] The type of `number_category<cpp_dec_float<Args...> >::type` is `std::integral_constant<int, number_kind_floating_point>`. More information on this type can be found in the [link boost_multiprecision.tut.floats.cpp_dec_float tutorial]. [endsect]