CHistogram.cpp

Go to the documentation of this file.

/* +------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)            |
   |                          http://www.mrpt.org/                          |
   |                                                                        |
   | Copyright (c) 2005-2017, Individual contributors, see AUTHORS file     |
   | See: http://www.mrpt.org/Authors - All rights reserved.                |
   | Released under BSD License. See details in http://www.mrpt.org/License |
   +------------------------------------------------------------------------+ */

#include "base-precomp.h"  // Precompiled headers

#include <mrpt/math/CHistogram.h>
#include <mrpt/math/utils.h>

using namespace mrpt;
using namespace mrpt::math;
using namespace mrpt::utils;

/*---------------------------------------------------------------
                                        Constructor
 ---------------------------------------------------------------*/
CHistogram::CHistogram(const double min, const double max, const size_t nBins)
        : m_min(min), m_max(max), m_bins(nBins, 0), m_count(0)
{
        ASSERT_(nBins > 0)
        ASSERT_(max > min)
        m_binSizeInv = nBins / (m_max - m_min);
}

/*---------------------------------------------------------------
                                                clear
 ---------------------------------------------------------------*/
void CHistogram::clear()
{
        m_bins.assign(m_bins.size(), 0);
        m_count = 0;
}

/*---------------------------------------------------------------
                                                        add
 ---------------------------------------------------------------*/
void CHistogram::add(const double x)
{
        if (x < m_min || x > m_max) return;

        size_t ind = static_cast<size_t>(m_binSizeInv * (x - m_min));

        m_bins[ind]++;
        m_count++;
}

/*---------------------------------------------------------------
                                        getBinCount
 ---------------------------------------------------------------*/
size_t CHistogram::getBinCount(const size_t index) const
{
        if (index >= m_bins.size()) THROW_EXCEPTION("Index out of bounds")

        return m_bins[index];
}

/*---------------------------------------------------------------
                                        getBinRatio
 ---------------------------------------------------------------*/
double CHistogram::getBinRatio(const size_t index) const
{
        if (index >= m_bins.size()) THROW_EXCEPTION("Index out of bounds")

        if (m_count)
                return m_bins[index] / double(m_count);
        else
                return 0;
}

/*---------------------------------------------------------------
                                        getHistogram
 ---------------------------------------------------------------*/
void CHistogram::getHistogram(
        std::vector<double>& x, std::vector<double>& hits) const
{
        linspace(m_min, m_max, m_bins.size(), x);
        const size_t N = m_bins.size();
        hits.resize(N);
        for (size_t i = 0; i < N; i++)
                hits[i] = static_cast<double>(
                        m_bins
                                [i]);  // metaprogramming::copy_container_typecasting(m_bins,);
}

/*---------------------------------------------------------------
                                        getHistogramNormalized
 ---------------------------------------------------------------*/
void CHistogram::getHistogramNormalized(
        std::vector<double>& x, std::vector<double>& hits) const
{
        const size_t N = m_bins.size();
        linspace(m_min, m_max, N, x);

        hits.resize(N);
        const double K = m_binSizeInv / m_count;
        for (size_t i = 0; i < N; i++) hits[i] = K * m_bins[i];
}