Reference documentation for deal.II version Git 497f915867 2021-09-17 22:46:48 +0200
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function.h
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15 
16 #ifndef dealii_function_h
17 #define dealii_function_h
18 
19 
20 #include <deal.II/base/config.h>
21 
24 #include <deal.II/base/point.h>
27 #include <deal.II/base/tensor.h>
28 
29 #include <functional>
30 #include <vector>
31 
33 
34 // Forward declarations
35 #ifndef DOXYGEN
36 template <typename number>
37 class Vector;
38 template <int rank, int dim, typename Number>
39 class TensorFunction;
40 #endif
41 
149 template <int dim, typename RangeNumberType = double>
150 class Function : public FunctionTime<
151  typename numbers::NumberTraits<RangeNumberType>::real_type>,
152  public Subscriptor
153 {
154 public:
159  static const unsigned int dimension = dim;
160 
164  const unsigned int n_components;
165 
169  using time_type = typename FunctionTime<
171 
177  explicit Function(const unsigned int n_components = 1,
178  const time_type initial_time = 0.0);
179 
183  Function(const Function &f) = default;
184 
206  virtual ~Function() override = 0;
207 
214  Function &
215  operator=(const Function &f);
216 
223  virtual RangeNumberType
224  value(const Point<dim> &p, const unsigned int component = 0) const;
225 
233  virtual void
235 
245  virtual void
246  value_list(const std::vector<Point<dim>> &points,
247  std::vector<RangeNumberType> & values,
248  const unsigned int component = 0) const;
249 
260  virtual void
261  vector_value_list(const std::vector<Point<dim>> & points,
262  std::vector<Vector<RangeNumberType>> &values) const;
263 
272  virtual void
273  vector_values(const std::vector<Point<dim>> & points,
274  std::vector<std::vector<RangeNumberType>> &values) const;
275 
281  gradient(const Point<dim> &p, const unsigned int component = 0) const;
282 
286  virtual void
288  const Point<dim> & p,
289  std::vector<Tensor<1, dim, RangeNumberType>> &gradients) const;
290 
297  virtual void
298  gradient_list(const std::vector<Point<dim>> & points,
300  const unsigned int component = 0) const;
301 
310  virtual void
312  const std::vector<Point<dim>> & points,
313  std::vector<std::vector<Tensor<1, dim, RangeNumberType>>> &gradients) const;
314 
324  virtual void
326  const std::vector<Point<dim>> & points,
327  std::vector<std::vector<Tensor<1, dim, RangeNumberType>>> &gradients) const;
328 
332  virtual RangeNumberType
333  laplacian(const Point<dim> &p, const unsigned int component = 0) const;
334 
339  virtual void
341 
345  virtual void
346  laplacian_list(const std::vector<Point<dim>> &points,
347  std::vector<RangeNumberType> & values,
348  const unsigned int component = 0) const;
349 
353  virtual void
354  vector_laplacian_list(const std::vector<Point<dim>> & points,
355  std::vector<Vector<RangeNumberType>> &values) const;
356 
362  hessian(const Point<dim> &p, const unsigned int component = 0) const;
363 
368  virtual void
370  const Point<dim> & p,
372 
376  virtual void
377  hessian_list(const std::vector<Point<dim>> & points,
379  const unsigned int component = 0) const;
380 
384  virtual void
386  const std::vector<Point<dim>> & points,
387  std::vector<std::vector<SymmetricTensor<2, dim, RangeNumberType>>> &values)
388  const;
389 
390 
396  virtual std::size_t
397  memory_consumption() const;
398 };
399 
400 
401 namespace Functions
402 {
409  template <int dim, typename RangeNumberType = double>
410  class ConstantFunction : public Function<dim, RangeNumberType>
411  {
412  public:
417  explicit ConstantFunction(const RangeNumberType value,
418  const unsigned int n_components = 1);
419 
425  explicit ConstantFunction(const std::vector<RangeNumberType> &values);
426 
432  explicit ConstantFunction(const Vector<RangeNumberType> &values);
433 
438  ConstantFunction(const RangeNumberType *begin_ptr,
439  const unsigned int n_components);
440 
441  virtual RangeNumberType
442  value(const Point<dim> &p, const unsigned int component = 0) const override;
443 
444  virtual void
445  vector_value(const Point<dim> & p,
446  Vector<RangeNumberType> &return_value) const override;
447 
448  virtual void
449  value_list(const std::vector<Point<dim>> &points,
450  std::vector<RangeNumberType> & return_values,
451  const unsigned int component = 0) const override;
452 
453  virtual void
455  const std::vector<Point<dim>> & points,
456  std::vector<Vector<RangeNumberType>> &return_values) const override;
457 
459  gradient(const Point<dim> & p,
460  const unsigned int component = 0) const override;
461 
462  virtual void
464  const Point<dim> & p,
465  std::vector<Tensor<1, dim, RangeNumberType>> &gradients) const override;
466 
467  virtual void
468  gradient_list(const std::vector<Point<dim>> & points,
470  const unsigned int component = 0) const override;
471 
472  virtual void
474  const std::vector<Point<dim>> & points,
475  std::vector<std::vector<Tensor<1, dim, RangeNumberType>>> &gradients)
476  const override;
477 
479  hessian(const Point<dim> & point,
480  const unsigned int component = 0) const override;
481 
482  virtual RangeNumberType
483  laplacian(const Point<dim> & point,
484  const unsigned int component = 0) const override;
485 
486  virtual std::size_t
487  memory_consumption() const override;
488 
489  protected:
493  std::vector<RangeNumberType> function_value_vector;
494  };
495 
496 
497 
509  template <int dim, typename RangeNumberType = double>
510  class ZeroFunction : public ConstantFunction<dim, RangeNumberType>
511  {
512  public:
516  explicit ZeroFunction(const unsigned int n_components = 1);
517  };
518 
529  template <int dim, typename RangeNumberType = double>
530  class IdentityFunction : public Function<dim, RangeNumberType>
531  {
532  public:
537 
541  virtual RangeNumberType
542  value(const Point<dim> &p, const unsigned int component = 0) const override;
543 
548  gradient(const Point<dim> & p,
549  const unsigned int component = 0) const override;
550 
554  virtual RangeNumberType
555  laplacian(const Point<dim> & p,
556  const unsigned int component = 0) const override;
557 
562  hessian(const Point<dim> & p,
563  const unsigned int component = 0) const override;
564  };
565 } // namespace Functions
566 
573 template <int dim, typename RangeNumberType = double>
576 
582 template <int dim, typename RangeNumberType = double>
585 
586 
587 
601 template <int dim, typename RangeNumberType = double>
603  : public Functions::ConstantFunction<dim, RangeNumberType>
604 {
605 public:
611  ComponentSelectFunction(const unsigned int selected,
612  const RangeNumberType value,
613  const unsigned int n_components);
614 
619  ComponentSelectFunction(const unsigned int selected,
620  const unsigned int n_components);
621 
629  ComponentSelectFunction(const std::pair<unsigned int, unsigned int> &selected,
630  const unsigned int n_components);
631 
632 
646  virtual void
647  substitute_function_value_with(
649 
653  virtual void
654  vector_value(const Point<dim> & p,
655  Vector<RangeNumberType> &return_value) const override;
656 
663  virtual void
665  const std::vector<Point<dim>> & points,
666  std::vector<Vector<RangeNumberType>> &values) const override;
667 
671  virtual std::size_t
672  memory_consumption() const override;
673 
674 protected:
678  const std::pair<unsigned int, unsigned int> selected_components;
679 };
680 
681 
682 
822 template <int dim, typename RangeNumberType = double>
823 class ScalarFunctionFromFunctionObject : public Function<dim, RangeNumberType>
824 {
825 public:
832  const std::function<RangeNumberType(const Point<dim> &)> &function_object);
833 
838  virtual RangeNumberType
839  value(const Point<dim> &p, const unsigned int component = 0) const override;
840 
841 private:
846  const std::function<RangeNumberType(const Point<dim> &)> function_object;
847 };
848 
849 
850 
889 template <int dim, typename RangeNumberType = double>
891  : public Function<dim, RangeNumberType>
892 {
893 public:
907  const std::function<RangeNumberType(const Point<dim> &)> &function_object,
908  const unsigned int selected_component,
909  const unsigned int n_components);
910 
915  virtual RangeNumberType
916  value(const Point<dim> &p, const unsigned int component = 0) const override;
917 
923  virtual void
924  vector_value(const Point<dim> & p,
925  Vector<RangeNumberType> &values) const override;
926 
927 private:
932  const std::function<RangeNumberType(const Point<dim> &)> function_object;
933 
938  const unsigned int selected_component;
939 };
940 
941 
977 template <int dim, typename RangeNumberType = double>
978 class FunctionFromFunctionObjects : public Function<dim, RangeNumberType>
979 {
980 public:
989  explicit FunctionFromFunctionObjects(const unsigned int n_components = 1,
990  const double initial_time = 0);
991 
1000  explicit FunctionFromFunctionObjects(
1001  const std::vector<std::function<RangeNumberType(const Point<dim> &)>>
1002  & values,
1003  const double initial_time = 0.0);
1004 
1014  const std::vector<std::function<RangeNumberType(const Point<dim> &)>>
1015  &values,
1016  const std::vector<
1017  std::function<Tensor<1, dim, RangeNumberType>(const Point<dim> &)>>
1018  & gradients,
1019  const double initial_time = 0.0);
1020 
1021 
1028  virtual RangeNumberType
1029  value(const Point<dim> &p, const unsigned int component = 0) const override;
1030 
1038  gradient(const Point<dim> & p,
1039  const unsigned int component = 0) const override;
1040 
1046  void
1047  set_function_values(
1048  const std::vector<std::function<RangeNumberType(const Point<dim> &)>>
1049  &values);
1050 
1056  void
1057  set_function_gradients(
1058  const std::vector<
1059  std::function<Tensor<1, dim, RangeNumberType>(const Point<dim> &)>>
1060  &gradients);
1061 
1062 private:
1066  std::vector<std::function<RangeNumberType(const Point<dim> &)>>
1067  function_values;
1068 
1072  std::vector<
1073  std::function<Tensor<1, dim, RangeNumberType>(const Point<dim> &)>>
1074  function_gradients;
1075 };
1076 
1077 
1113 template <int dim, typename RangeNumberType = double>
1114 class VectorFunctionFromTensorFunction : public Function<dim, RangeNumberType>
1115 {
1116 public:
1134  const TensorFunction<1, dim, RangeNumberType> &tensor_function,
1135  const unsigned int selected_component = 0,
1136  const unsigned int n_components = dim);
1137 
1142  virtual ~VectorFunctionFromTensorFunction() override = default;
1143 
1147  virtual RangeNumberType
1148  value(const Point<dim> &p, const unsigned int component = 0) const override;
1149 
1155  virtual void
1156  vector_value(const Point<dim> & p,
1157  Vector<RangeNumberType> &values) const override;
1158 
1166  virtual void
1168  const std::vector<Point<dim>> & points,
1169  std::vector<Vector<RangeNumberType>> &value_list) const override;
1170 
1171 private:
1177 
1184  const unsigned int selected_component;
1185 };
1186 
1187 
1188 #ifndef DOXYGEN
1189 // icc 2018 complains about an undefined reference
1190 // if we put this in the templates.h file
1191 //
1192 // The destructor is pure virtual so we can't default it
1193 // in the declaration.
1194 template <int dim, typename RangeNumberType>
1196 #endif
1197 
1198 
1200 
1201 #endif
Function(const unsigned int n_components=1, const time_type initial_time=0.0)
const unsigned int n_components
Definition: function.h:164
virtual void vector_hessian_list(const std::vector< Point< dim >> &points, std::vector< std::vector< SymmetricTensor< 2, dim, RangeNumberType >>> &values) const
virtual void vector_gradient_list(const std::vector< Point< dim >> &points, std::vector< std::vector< Tensor< 1, dim, RangeNumberType >>> &gradients) const
static const unsigned int dimension
Definition: function.h:159
virtual void vector_laplacian(const Point< dim > &p, Vector< RangeNumberType > &values) const
virtual void vector_hessian(const Point< dim > &p, std::vector< SymmetricTensor< 2, dim, RangeNumberType >> &values) const
virtual void vector_gradients(const std::vector< Point< dim >> &points, std::vector< std::vector< Tensor< 1, dim, RangeNumberType >>> &gradients) const
Function & operator=(const Function &f)
typename FunctionTime< typename numbers::NumberTraits< RangeNumberType >::real_type >::time_type time_type
Definition: function.h:170
virtual void vector_value_list(const std::vector< Point< dim >> &points, std::vector< Vector< RangeNumberType >> &values) const
virtual void vector_values(const std::vector< Point< dim >> &points, std::vector< std::vector< RangeNumberType >> &values) const
virtual SymmetricTensor< 2, dim, RangeNumberType > hessian(const Point< dim > &p, const unsigned int component=0) const
virtual std::size_t memory_consumption() const
#define DEAL_II_NAMESPACE_CLOSE
Definition: config.h:401
virtual void vector_value(const Point< dim > &p, Vector< RangeNumberType > &values) const
Point< spacedim > point(const gp_Pnt &p, const double tolerance=1e-10)
Definition: utilities.cc:185
virtual void hessian_list(const std::vector< Point< dim >> &points, std::vector< SymmetricTensor< 2, dim, RangeNumberType >> &values, const unsigned int component=0) const
const TensorFunction< 1, dim, RangeNumberType > & tensor_function
Definition: function.h:1176
virtual void vector_laplacian_list(const std::vector< Point< dim >> &points, std::vector< Vector< RangeNumberType >> &values) const
virtual Tensor< 1, dim, RangeNumberType > gradient(const Point< dim > &p, const unsigned int component=0) const
Number time_type
const std::pair< unsigned int, unsigned int > selected_components
Definition: function.h:678
Functions::ZeroFunction< dim, RangeNumberType > ZeroFunction
Definition: function.h:584
virtual RangeNumberType laplacian(const Point< dim > &p, const unsigned int component=0) const
Definition: tensor.h:506
#define DEAL_II_NAMESPACE_OPEN
Definition: config.h:400
virtual void value_list(const std::vector< Point< dim >> &points, std::vector< RangeNumberType > &values, const unsigned int component=0) const
virtual ~Function() override=0
const unsigned int selected_component
Definition: function.h:1184
Functions::ConstantFunction< dim, RangeNumberType > ConstantFunction
Definition: function.h:575
const unsigned int selected_component
Definition: function.h:938
virtual RangeNumberType value(const Point< dim > &p, const unsigned int component=0) const
#define DEAL_II_DEPRECATED
Definition: config.h:160
virtual void gradient_list(const std::vector< Point< dim >> &points, std::vector< Tensor< 1, dim, RangeNumberType >> &gradients, const unsigned int component=0) const
virtual void vector_gradient(const Point< dim > &p, std::vector< Tensor< 1, dim, RangeNumberType >> &gradients) const
std::vector< RangeNumberType > function_value_vector
Definition: function.h:493
virtual void laplacian_list(const std::vector< Point< dim >> &points, std::vector< RangeNumberType > &values, const unsigned int component=0) const