text: /* +------------------------------------------------------------------------+
     |                     Mobile Robot Programming Toolkit (MRPT)            |
     |                          https://www.mrpt.org/                         |
     |                                                                        |
     | Copyright (c) 2005-2019, Individual contributors, see AUTHORS file     |
     | See: https://www.mrpt.org/Authors - All rights reserved.               |
     | Released under BSD License. See: https://www.mrpt.org/License          |
     +------------------------------------------------------------------------+ */
  #pragma once
  
  #include <mrpt/core/bits_math.h>  // DEG2RAD()
  #include <mrpt/poses/CPose2DGridTemplate.h>
  #include <mrpt/poses/CPosePDF.h>
  
  namespace mrpt::poses
  {
  /** Declares a class that represents a Probability Distribution
   *    function (PDF) of a 2D pose (x,y,phi).
   *   This class implements that PDF using a 3D grid.
   *
   * \sa CPose2D, CPosePDF, CPose2DGridTemplate
   * \ingroup poses_pdf_grp
   */
  class CPosePDFGrid : public CPosePDF, public CPose2DGridTemplate<double>
  {
  	DEFINE_SERIALIZABLE(CPosePDFGrid)
  
     protected:
     public:
  	/** Constructor: Initializes a, uniform distribution over the whole given
  	 * range.
  	 */
  	CPosePDFGrid(
  		double xMin = -1.0f, double xMax = 1.0f, double yMin = -1.0f,
  		double yMax = 1.0f, double resolutionXY = 0.5f,
  		double resolutionPhi = mrpt::DEG2RAD(180.0), double phiMin = -M_PI,
  		double phiMax = M_PI);
  
  	/** Destructor */
  	~CPosePDFGrid() override;
  
  	/** Copy operator, translating if necesary (for example, between particles
  	 * and gaussian representations) */
  	void copyFrom(const CPosePDF& o) override;
  
  	/** Normalizes the PDF, such as all cells sum the unity. */
  	void normalize();
  	/** Assigns the same value to all the cells in the grid, so the sum 1. */
  	void uniformDistribution();
  
  	void getMean(CPose2D& mean_pose) const override;
  
  	std::tuple<cov_mat_t, type_value> getCovarianceAndMean() const override;
  
  	/** Save the contents of the 3D grid in one file, as a vertical
  	 * concatenation of rectangular matrix for the different "PHI" discrete
  	 * levels, and the size in X,Y,and PHI in another file named
  	 * "<filename>_dims.txt". \return false on error */
  	bool saveToTextFile(const std::string& dataFile) const override;
  
  	/** this = p (+) this. This can be used to convert a PDF from local
  	 * coordinates to global, providing the point (newReferenceBase) from which
  	 *   "to project" the current pdf. Result PDF substituted the currently
  	 * stored one in the object. */
  	void changeCoordinatesReference(const CPose3D& newReferenceBase) override;
  	/** Bayesian fusion of 2 densities (In the grid representation this becomes
  	 * a pointwise multiplication) */
  	void bayesianFusion(
  		const CPosePDF& p1, const CPosePDF& p2,
  		const double minMahalanobisDistToDrop = 0) override;
  	/** Returns a new PDF such as: NEW_PDF = (0,0,0) - THIS_PDF */
  	void inverse(CPosePDF& o) const override;
  	/** Draws a single sample from the distribution (WARNING: weights are
  	 * assumed to be normalized!) */
  	void drawSingleSample(CPose2D& outPart) const override;
  	/** Draws a number of samples from the distribution, and saves as a list of
  	 * 1x3 vectors, where each row contains a (x,y,phi) datum. */
  	void drawManySamples(
  		size_t N,
  		std::vector<mrpt::math::CVectorDouble>& outSamples) const override;
  
  };  // End of class def.
  }  // namespace mrpt::poses
  