Reference documentation for deal.II version Git 7edbc71 2017-07-25 01:57:43 -0600
Public Types | Public Member Functions | List of all members
TensorFunction< rank, dim, Number > Class Template Reference

#include <deal.II/base/tensor_function.h>

Inheritance diagram for TensorFunction< rank, dim, Number >:
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Public Types

typedef Tensor< rank, dim, Number > value_type
 

Public Member Functions

 TensorFunction (const Number initial_time=Number(0.0))
 
virtual ~TensorFunction ()
 
virtual value_type value (const Point< dim > &p) const
 
virtual void value_list (const std::vector< Point< dim > > &points, std::vector< value_type > &values) const
 
virtual gradient_type gradient (const Point< dim > &p) const
 
virtual void gradient_list (const std::vector< Point< dim > > &points, std::vector< gradient_type > &gradients) const
 
- Public Member Functions inherited from FunctionTime< Number >
 FunctionTime (const Number initial_time=Number(0.0))
 
virtual ~FunctionTime ()
 
Number get_time () const
 
virtual void set_time (const Number new_time)
 
virtual void advance_time (const Number delta_t)
 
- Public Member Functions inherited from Subscriptor
 Subscriptor ()
 
 Subscriptor (const Subscriptor &)
 
 Subscriptor (Subscriptor &&)
 
virtual ~Subscriptor ()
 
Subscriptoroperator= (const Subscriptor &)
 
Subscriptoroperator= (Subscriptor &&)
 
void subscribe (const char *identifier=nullptr) const
 
void unsubscribe (const char *identifier=nullptr) const
 
unsigned int n_subscriptions () const
 
void list_subscribers () const
 
template<class Archive >
void serialize (Archive &ar, const unsigned int version)
 

Additional Inherited Members

- Static Public Member Functions inherited from Subscriptor
static::ExceptionBase & ExcInUse (int arg1, char *arg2, std::string &arg3)
 
static::ExceptionBase & ExcNoSubscriber (char *arg1, char *arg2)
 

Detailed Description

template<int rank, int dim, typename Number = double>
class TensorFunction< rank, dim, Number >

This class is a model for a tensor valued function. The interface of the class is mostly the same as that for the Function class, with the exception that it does not support vector-valued functions with several components, but that the return type is always tensor-valued. The returned values of the evaluation of objects of this type are always whole tensors, while for the Function class, one can ask for a specific component only, or use the vector_value function, which however does not return the value, but rather writes it into the address provided by its second argument. The reason for the different behaviour of the classes is that in the case of tensor valued functions, the size of the argument is known to the compiler a priori, such that the correct amount of memory can be allocated on the stack for the return value; on the other hand, for the vector valued functions, the size is not known to the compiler, so memory has to be allocated on the heap, resulting in relatively expensive copy operations. One can therefore consider this class a specialization of the Function class for which the size is known. An additional benefit is that tensors of arbitrary rank can be returned, not only vectors, as for them the size can be determined similarly simply.

Author
Guido Kanschat, 1999

Definition at line 35 of file function.h.

Member Typedef Documentation

template<int rank, int dim, typename Number = double>
typedef Tensor<rank,dim,Number> TensorFunction< rank, dim, Number >::value_type

Define typedefs for the return types of the value functions.

Definition at line 63 of file tensor_function.h.

Constructor & Destructor Documentation

template<int rank, int dim, typename Number = double>
TensorFunction< rank, dim, Number >::TensorFunction ( const Number  initial_time = Number(0.0))

Constructor. May take an initial value for the time variable, which defaults to zero.

template<int rank, int dim, typename Number = double>
virtual TensorFunction< rank, dim, Number >::~TensorFunction ( )
virtual

Virtual destructor; absolutely necessary in this case, as classes are usually not used by their true type, but rather through pointers to this base class.

Member Function Documentation

template<int rank, int dim, typename Number = double>
virtual value_type TensorFunction< rank, dim, Number >::value ( const Point< dim > &  p) const
virtual

Return the value of the function at the given point.

Reimplemented in ConstantTensorFunction< rank, dim, Number >.

template<int rank, int dim, typename Number = double>
virtual void TensorFunction< rank, dim, Number >::value_list ( const std::vector< Point< dim > > &  points,
std::vector< value_type > &  values 
) const
virtual

Set values to the point values of the function at the points. It is assumed that values already has the right size, i.e. the same size as the points array.

template<int rank, int dim, typename Number = double>
virtual gradient_type TensorFunction< rank, dim, Number >::gradient ( const Point< dim > &  p) const
virtual

Return the gradient of the function at the given point.

Reimplemented in ConstantTensorFunction< rank, dim, Number >.

template<int rank, int dim, typename Number = double>
virtual void TensorFunction< rank, dim, Number >::gradient_list ( const std::vector< Point< dim > > &  points,
std::vector< gradient_type > &  gradients 
) const
virtual

Set gradients to the gradients of the function at the points. It is assumed that values already has the right size, i.e. the same size as the points array.


The documentation for this class was generated from the following files: