boost/accumulators/statistics/rolling_window.hpp
///////////////////////////////////////////////////////////////////////////////
// rolling_window.hpp
//
// Copyright 2008 Eric Niebler. 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)
#ifndef BOOST_ACCUMULATORS_STATISTICS_ROLLING_WINDOW_HPP_EAN_26_12_2008
#define BOOST_ACCUMULATORS_STATISTICS_ROLLING_WINDOW_HPP_EAN_26_12_2008
#include <cstddef>
#include <boost/version.hpp>
#include <boost/assert.hpp>
#include <boost/circular_buffer.hpp>
#include <boost/range/iterator_range.hpp>
#include <boost/accumulators/framework/extractor.hpp>
#include <boost/accumulators/framework/depends_on.hpp>
#include <boost/accumulators/framework/accumulator_base.hpp>
#include <boost/accumulators/framework/parameters/sample.hpp>
#include <boost/accumulators/framework/parameters/accumulator.hpp>
#include <boost/accumulators/numeric/functional.hpp>
#include <boost/accumulators/statistics_fwd.hpp>
namespace boost { namespace accumulators
{
///////////////////////////////////////////////////////////////////////////////
// tag::rolling_window::size named parameter
BOOST_PARAMETER_NESTED_KEYWORD(tag, rolling_window_size, window_size)
namespace impl
{
///////////////////////////////////////////////////////////////////////////////
// rolling_window_plus1_impl
// stores the latest N+1 samples, where N is specified at construction time
// with the rolling_window_size named parameter
template<typename Sample>
struct rolling_window_plus1_impl
: accumulator_base
{
typedef typename circular_buffer<Sample>::const_iterator const_iterator;
typedef iterator_range<const_iterator> result_type;
template<typename Args>
rolling_window_plus1_impl(Args const & args)
: buffer_(args[rolling_window_size] + 1)
{}
#if BOOST_VERSION < 103600
// Before Boost 1.36, copying a circular buffer didn't copy
// it's capacity, and we need that behavior.
rolling_window_plus1_impl(rolling_window_plus1_impl const &that)
: buffer_(that.buffer_)
{
this->buffer_.set_capacity(that.buffer_.capacity());
}
rolling_window_plus1_impl &operator =(rolling_window_plus1_impl const &that)
{
this->buffer_ = that.buffer_;
this->buffer_.set_capacity(that.buffer_.capacity());
}
#endif
template<typename Args>
void operator ()(Args const &args)
{
this->buffer_.push_back(args[sample]);
}
bool full() const
{
return this->buffer_.full();
}
// The result of a shifted rolling window is the range including
// everything except the most recently added element.
result_type result(dont_care) const
{
return result_type(this->buffer_.begin(), this->buffer_.end());
}
private:
circular_buffer<Sample> buffer_;
};
template<typename Args>
bool is_rolling_window_plus1_full(Args const &args)
{
return find_accumulator<tag::rolling_window_plus1>(args[accumulator]).full();
}
///////////////////////////////////////////////////////////////////////////////
// rolling_window_impl
// stores the latest N samples, where N is specified at construction type
// with the rolling_window_size named parameter
template<typename Sample>
struct rolling_window_impl
: accumulator_base
{
typedef typename circular_buffer<Sample>::const_iterator const_iterator;
typedef iterator_range<const_iterator> result_type;
rolling_window_impl(dont_care)
{}
template<typename Args>
result_type result(Args const &args) const
{
return rolling_window_plus1(args).advance_begin(is_rolling_window_plus1_full(args));
}
};
} // namespace impl
///////////////////////////////////////////////////////////////////////////////
// tag::rolling_window_plus1
// tag::rolling_window
//
namespace tag
{
struct rolling_window_plus1
: depends_on<>
, tag::rolling_window_size
{
/// INTERNAL ONLY
///
typedef accumulators::impl::rolling_window_plus1_impl< mpl::_1 > impl;
#ifdef BOOST_ACCUMULATORS_DOXYGEN_INVOKED
/// tag::rolling_window::size named parameter
static boost::parameter::keyword<tag::rolling_window_size> const window_size;
#endif
};
struct rolling_window
: depends_on< rolling_window_plus1 >
{
/// INTERNAL ONLY
///
typedef accumulators::impl::rolling_window_impl< mpl::_1 > impl;
#ifdef BOOST_ACCUMULATORS_DOXYGEN_INVOKED
/// tag::rolling_window::size named parameter
static boost::parameter::keyword<tag::rolling_window_size> const window_size;
#endif
};
} // namespace tag
///////////////////////////////////////////////////////////////////////////////
// extract::rolling_window_plus1
// extract::rolling_window
//
namespace extract
{
extractor<tag::rolling_window_plus1> const rolling_window_plus1 = {};
extractor<tag::rolling_window> const rolling_window = {};
BOOST_ACCUMULATORS_IGNORE_GLOBAL(rolling_window_plus1)
BOOST_ACCUMULATORS_IGNORE_GLOBAL(rolling_window)
}
using extract::rolling_window_plus1;
using extract::rolling_window;
}} // namespace boost::accumulators
#endif