#include <CGAL/Isosurfacing_3/Interpolated_discrete_gradients_3.h>
template<typename Grid, typename InterpolationScheme = Trilinear_interpolation<Grid>>
class CGAL::Isosurfacing::Interpolated_discrete_gradients_3< Grid, InterpolationScheme >
Class template for a gradient field that is computed using discrete values and interpolation. 
- Is model of
 
IsosurfacingValueField_3  
- Template Parameters
 - 
  
  
 
- Examples
 - Isosurfacing_3/contouring_discrete_data.cpp.
 
 | 
| 
  | Interpolated_discrete_gradients_3 (const Grid &grid, const InterpolationScheme &interpolation=InterpolationScheme()) | 
|   | 
| template<typename ValueField >  | 
| void  | compute_discrete_gradients (const ValueField &values) | 
|   | computes (using finite difference) and stores gradients at all vertices of the grid.  
  | 
|   | 
| Vector_3 &  | operator() (const std::size_t i, const std::size_t j, const std::size_t k) | 
|   | returns the gradient stored at the grid vertex described by its three indices.  
  | 
|   | 
| const Vector_3 &  | operator() (const std::size_t i, const std::size_t j, const std::size_t k) const | 
|   | returns the gradient stored at the grid vertex described by a set of indices.  
  | 
|   | 
| 
Vector_3  | operator() (const Point_3 &p) const | 
|   | returns the gradient at a given point p. 
  | 
|   | 
◆ compute_discrete_gradients()
template<typename Grid , typename InterpolationScheme  = Trilinear_interpolation<Grid>> 
template<typename ValueField > 
      
 
computes (using finite difference) and stores gradients at all vertices of the grid. 
- Template Parameters
 - 
  
  
 
- Parameters
 - 
  
    | values | a field of values whose gradient are being computed  | 
  
   
 
 
◆ operator()() [1/2]
template<typename Grid , typename InterpolationScheme  = Trilinear_interpolation<Grid>> 
      
 
returns the gradient stored at the grid vertex described by its three indices. 
- Note
 - This function can be used to set the gradient at a grid vertex.
 
- Parameters
 - 
  
    | i | the index in the x direction  | 
    | j | the index in the y direction  | 
    | k | the index in the z direction | 
  
   
- Precondition
 i < xdim() and j < ydim() and k < zdim() 
 
 
◆ operator()() [2/2]
template<typename Grid , typename InterpolationScheme  = Trilinear_interpolation<Grid>> 
      
 
returns the gradient stored at the grid vertex described by a set of indices. 
- Parameters
 - 
  
    | i | the index in the x direction  | 
    | j | the index in the y direction  | 
    | k | the index in the z direction | 
  
   
- Precondition
 i < xdim() and j < ydim() and k < zdim()