diff options
Diffstat (limited to 'boost/accumulators/statistics/weighted_p_square_cumulative_distribution.hpp')
-rw-r--r-- | boost/accumulators/statistics/weighted_p_square_cumulative_distribution.hpp | 261 |
1 files changed, 9 insertions, 252 deletions
diff --git a/boost/accumulators/statistics/weighted_p_square_cumulative_distribution.hpp b/boost/accumulators/statistics/weighted_p_square_cumulative_distribution.hpp index 290f090fe5..918970e8dc 100644 --- a/boost/accumulators/statistics/weighted_p_square_cumulative_distribution.hpp +++ b/boost/accumulators/statistics/weighted_p_square_cumulative_distribution.hpp @@ -1,262 +1,19 @@ /////////////////////////////////////////////////////////////////////////////// // weighted_p_square_cumulative_distribution.hpp // -// Copyright 2006 Daniel Egloff, Olivier Gygi. Distributed under the Boost +// Copyright 2012 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_WEIGHTED_P_SQUARE_CUMULATIVE_DISTRIBUTION_HPP_DE_01_01_2006 -#define BOOST_ACCUMULATORS_STATISTICS_WEIGHTED_P_SQUARE_CUMULATIVE_DISTRIBUTION_HPP_DE_01_01_2006 +#ifndef BOOST_ACCUMULATORS_STATISTICS_WEIGHTED_P_SQUARE_CUMULATIVE_DISTRIBUTION_HPP_03_19_2012 +#define BOOST_ACCUMULATORS_STATISTICS_WEIGHTED_P_SQUARE_CUMULATIVE_DISTRIBUTION_HPP_03_19_2012 -#include <vector> -#include <functional> -#include <boost/parameter/keyword.hpp> -#include <boost/mpl/placeholders.hpp> -#include <boost/range.hpp> -#include <boost/accumulators/framework/accumulator_base.hpp> -#include <boost/accumulators/framework/extractor.hpp> -#include <boost/accumulators/numeric/functional.hpp> -#include <boost/accumulators/framework/parameters/sample.hpp> -#include <boost/accumulators/statistics_fwd.hpp> -#include <boost/accumulators/statistics/count.hpp> -#include <boost/accumulators/statistics/sum.hpp> -#include <boost/accumulators/statistics/p_square_cumulative_distribution.hpp> // for named parameter p_square_cumulative_distribution_num_cells - -namespace boost { namespace accumulators -{ - -namespace impl -{ - /////////////////////////////////////////////////////////////////////////////// - // weighted_p_square_cumulative_distribution_impl - // cumulative distribution calculation (as histogram) - /** - @brief Histogram calculation of the cumulative distribution with the \f$P^2\f$ algorithm for weighted samples - - A histogram of the sample cumulative distribution is computed dynamically without storing samples - based on the \f$ P^2 \f$ algorithm for weighted samples. The returned histogram has a specifiable - amount (num_cells) equiprobable (and not equal-sized) cells. - - Note that applying importance sampling results in regions to be more and other regions to be less - accurately estimated than without importance sampling, i.e., with unweighted samples. - - For further details, see - - R. Jain and I. Chlamtac, The P^2 algorithmus for dynamic calculation of quantiles and - histograms without storing observations, Communications of the ACM, - Volume 28 (October), Number 10, 1985, p. 1076-1085. - - @param p_square_cumulative_distribution_num_cells - */ - template<typename Sample, typename Weight> - struct weighted_p_square_cumulative_distribution_impl - : accumulator_base - { - typedef typename numeric::functional::multiplies<Sample, Weight>::result_type weighted_sample; - typedef typename numeric::functional::average<weighted_sample, std::size_t>::result_type float_type; - typedef std::vector<std::pair<float_type, float_type> > histogram_type; - typedef std::vector<float_type> array_type; - // for boost::result_of - typedef iterator_range<typename histogram_type::iterator> result_type; - - template<typename Args> - weighted_p_square_cumulative_distribution_impl(Args const &args) - : num_cells(args[p_square_cumulative_distribution_num_cells]) - , heights(num_cells + 1) - , actual_positions(num_cells + 1) - , desired_positions(num_cells + 1) - , histogram(num_cells + 1) - , is_dirty(true) - { - } - - template<typename Args> - void operator ()(Args const &args) - { - this->is_dirty = true; - - std::size_t cnt = count(args); - std::size_t sample_cell = 1; // k - std::size_t b = this->num_cells; - - // accumulate num_cells + 1 first samples - if (cnt <= b + 1) - { - this->heights[cnt - 1] = args[sample]; - this->actual_positions[cnt - 1] = args[weight]; - - // complete the initialization of heights by sorting - if (cnt == b + 1) - { - //std::sort(this->heights.begin(), this->heights.end()); - - // TODO: we need to sort the initial samples (in heights) in ascending order and - // sort their weights (in actual_positions) the same way. The following lines do - // it, but there must be a better and more efficient way of doing this. - typename array_type::iterator it_begin, it_end, it_min; - - it_begin = this->heights.begin(); - it_end = this->heights.end(); - - std::size_t pos = 0; - - while (it_begin != it_end) - { - it_min = std::min_element(it_begin, it_end); - std::size_t d = std::distance(it_begin, it_min); - std::swap(*it_begin, *it_min); - std::swap(this->actual_positions[pos], this->actual_positions[pos + d]); - ++it_begin; - ++pos; - } - - // calculate correct initial actual positions - for (std::size_t i = 1; i < b; ++i) - { - this->actual_positions[i] += this->actual_positions[i - 1]; - } - } - } - else - { - // find cell k such that heights[k-1] <= args[sample] < heights[k] and adjust extreme values - if (args[sample] < this->heights[0]) - { - this->heights[0] = args[sample]; - this->actual_positions[0] = args[weight]; - sample_cell = 1; - } - else if (this->heights[b] <= args[sample]) - { - this->heights[b] = args[sample]; - sample_cell = b; - } - else - { - typename array_type::iterator it; - it = std::upper_bound( - this->heights.begin() - , this->heights.end() - , args[sample] - ); - - sample_cell = std::distance(this->heights.begin(), it); - } - - // increment positions of markers above sample_cell - for (std::size_t i = sample_cell; i < b + 1; ++i) - { - this->actual_positions[i] += args[weight]; - } - - // determine desired marker positions - for (std::size_t i = 1; i < b + 1; ++i) - { - this->desired_positions[i] = this->actual_positions[0] - + numeric::average((i-1) * (sum_of_weights(args) - this->actual_positions[0]), b); - } - - // adjust heights of markers 2 to num_cells if necessary - for (std::size_t i = 1; i < b; ++i) - { - // offset to desire position - float_type d = this->desired_positions[i] - this->actual_positions[i]; - - // offset to next position - float_type dp = this->actual_positions[i + 1] - this->actual_positions[i]; - - // offset to previous position - float_type dm = this->actual_positions[i - 1] - this->actual_positions[i]; - - // height ds - float_type hp = (this->heights[i + 1] - this->heights[i]) / dp; - float_type hm = (this->heights[i - 1] - this->heights[i]) / dm; - - if ( ( d >= 1. && dp > 1. ) || ( d <= -1. && dm < -1. ) ) - { - short sign_d = static_cast<short>(d / std::abs(d)); - - // try adjusting heights[i] using p-squared formula - float_type h = this->heights[i] + sign_d / (dp - dm) * ( (sign_d - dm) * hp + (dp - sign_d) * hm ); - - if ( this->heights[i - 1] < h && h < this->heights[i + 1] ) - { - this->heights[i] = h; - } - else - { - // use linear formula - if (d>0) - { - this->heights[i] += hp; - } - if (d<0) - { - this->heights[i] -= hm; - } - } - this->actual_positions[i] += sign_d; - } - } - } - } - - template<typename Args> - result_type result(Args const &args) const - { - if (this->is_dirty) - { - this->is_dirty = false; - - // creates a vector of std::pair where each pair i holds - // the values heights[i] (x-axis of histogram) and - // actual_positions[i] / sum_of_weights (y-axis of histogram) - - for (std::size_t i = 0; i < this->histogram.size(); ++i) - { - this->histogram[i] = std::make_pair(this->heights[i], numeric::average(this->actual_positions[i], sum_of_weights(args))); - } - } - - return make_iterator_range(this->histogram); - } - - private: - std::size_t num_cells; // number of cells b - array_type heights; // q_i - array_type actual_positions; // n_i - array_type desired_positions; // n'_i - mutable histogram_type histogram; // histogram - mutable bool is_dirty; - }; - -} // namespace detail - -/////////////////////////////////////////////////////////////////////////////// -// tag::weighted_p_square_cumulative_distribution -// -namespace tag -{ - struct weighted_p_square_cumulative_distribution - : depends_on<count, sum_of_weights> - , p_square_cumulative_distribution_num_cells - { - typedef accumulators::impl::weighted_p_square_cumulative_distribution_impl<mpl::_1, mpl::_2> impl; - }; -} - -/////////////////////////////////////////////////////////////////////////////// -// extract::weighted_p_square_cumulative_distribution -// -namespace extract -{ - extractor<tag::weighted_p_square_cumulative_distribution> const weighted_p_square_cumulative_distribution = {}; - - BOOST_ACCUMULATORS_IGNORE_GLOBAL(weighted_p_square_cumulative_distribution) -} - -using extract::weighted_p_square_cumulative_distribution; +#if defined(_MSC_VER) || defined(__BORLANDC__) || defined(__DMC__) +# pragma message ("Warning: This header is deprecated. Please use: boost/accumulators/statistics/weighted_p_square_cumul_dist.hpp") +#elif defined(__GNUC__) || defined(__HP_aCC) || defined(__SUNPRO_CC) || defined(__IBMCPP__) +# warning "This header is deprecated. Please use: boost/accumulators/statistics/weighted_p_square_cumul_dist.hpp" +#endif -}} // namespace boost::accumulators +#include <boost/accumulators/statistics/weighted_p_square_cumul_dist.hpp> #endif |