Line data    Source code

       1             : // The libMesh Finite Element Library.
       2             : // Copyright (C) 2002-2025 Benjamin S. Kirk, John W. Peterson, Roy H. Stogner
       3             : 
       4             : // This library is free software; you can redistribute it and/or
       5             : // modify it under the terms of the GNU Lesser General Public
       6             : // License as published by the Free Software Foundation; either
       7             : // version 2.1 of the License, or (at your option) any later version.
       8             : 
       9             : // This library is distributed in the hope that it will be useful,
      10             : // but WITHOUT ANY WARRANTY; without even the implied warranty of
      11             : // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      12             : // Lesser General Public License for more details.
      13             : 
      14             : // You should have received a copy of the GNU Lesser General Public
      15             : // License along with this library; if not, write to the Free Software
      16             : // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
      17             : 
      18             : 
      19             : 
      20             : #ifndef LIBMESH_RADIAL_BASIS_INTERPOLATION_H
      21             : #define LIBMESH_RADIAL_BASIS_INTERPOLATION_H
      22             : 
      23             : // Local includes
      24             : #include "libmesh/libmesh_config.h"
      25             : #include "libmesh/libmesh_common.h"
      26             : #include "libmesh/meshfree_interpolation.h"
      27             : #include "libmesh/radial_basis_functions.h"
      28             : #include "libmesh/bounding_box.h"
      29             : 
      30             : 
      31             : 
      32             : namespace libMesh
      33             : {
      34             : 
      35             : /**
      36             :  * Radial Basis Function interpolation.
      37             :  *
      38             :  * \author Benjamin S. Kirk
      39             :  * \date 2013
      40             :  * \brief Does radial basis function interpolation using Nanoflann.
      41             :  */
      42             : template <unsigned int KDDim, class RBF = WendlandRBF<KDDim, 2>>
      43             : class RadialBasisInterpolation : public InverseDistanceInterpolation<KDDim>
      44             : {
      45             :   /**
      46             :    * Bring base class data into our namespace.
      47             :    */
      48             :   using InverseDistanceInterpolation<KDDim>::_src_pts;
      49             :   using InverseDistanceInterpolation<KDDim>::_src_vals;
      50             :   using InverseDistanceInterpolation<KDDim>::_names;
      51             : 
      52             : protected:
      53             : 
      54             :   /**
      55             :    * Bounding box for our source points.
      56             :    */
      57             :   BoundingBox _src_bbox;
      58             : 
      59             :   /**
      60             :    * basis coefficients.
      61             :    */
      62             :   std::vector<Number> _weights;
      63             : 
      64             :   /**
      65             :    * Diagonal of the bounding box.
      66             :    */
      67             :   Real _r_bbox;
      68             : 
      69             :   /**
      70             :    * Diagonal override
      71             :    */
      72             :   Real _r_override;
      73             : 
      74             : public:
      75             : 
      76             :   /**
      77             :    * Constructor.
      78             :    */
      79           0 :   RadialBasisInterpolation (const libMesh::Parallel::Communicator & comm_in,
      80             :                             Real radius=-1) :
      81             :     InverseDistanceInterpolation<KDDim> (comm_in,8,2),
      82           0 :     _r_bbox(0.),
      83           0 :     _r_override(radius)
      84           0 :   { }
      85             : 
      86             :   /**
      87             :    * Clears all internal data structures and restores to a
      88             :    * pristine state.
      89             :    */
      90             :   virtual void clear() override;
      91             : 
      92             :   /**
      93             :    * Prepares data structures for use.
      94             :    */
      95             :   virtual void prepare_for_use () override;
      96             : 
      97             :   /**
      98             :    * Interpolate source data at target points.
      99             :    * Pure virtual, must be overridden in derived classes.
     100             :    */
     101             :   virtual void interpolate_field_data (const std::vector<std::string> & field_names,
     102             :                                        const std::vector<Point> & tgt_pts,
     103             :                                        std::vector<Number> & tgt_vals) const override;
     104             : };
     105             : 
     106             : } // namespace libMesh
     107             : 
     108             : 
     109             : #endif // #define LIBMESH_RADIAL_BASIS_INTERPOLATION_H