libMesh::CompositeFunction< Output > Class Template Reference

A function that returns a vector whose components are defined by multiple functions. More...

#include <composite_function.h>

Inheritance diagram for libMesh::CompositeFunction< Output >:

Public Member Functions
	CompositeFunction ()=default
	CompositeFunction (CompositeFunction &&)=default
	This class can be default move constructed and assigned. More...
CompositeFunction &	operator= (CompositeFunction &&)=default
	CompositeFunction (const CompositeFunction &)=delete
	This class contains unique_ptr members so it can't be default copied or assigned. More...
CompositeFunction &	operator= (const CompositeFunction &)=delete
virtual	~CompositeFunction ()=default
	The subfunctions vector is automatically cleaned up. More...
void	attach_subfunction (const FunctionBase< Output > &f, std::vector< unsigned int > index_map)
	Attach a new subfunction, along with a map from the indices of the attached subfunction to the indices of the composed function. More...
virtual Output	operator() (const Point &p, const Real time=0) override
virtual void	operator() (const Point &p, const Real time, DenseVector< Output > &output) override
	Evaluation function for time-dependent vector-valued functions. More...
virtual Output	component (unsigned int i, const Point &p, Real time) override
virtual std::unique_ptr< FunctionBase< Output > >	clone () const override
unsigned int	n_subfunctions () const
unsigned int	n_components () const
virtual void	init ()
	The actual initialization process. More...
virtual void	clear ()
	Clears the function. More...
void	operator() (const Point &p, DenseVector< Output > &output)
	Evaluation function for time-independent vector-valued functions. More...
bool	initialized () const
void	set_is_time_dependent (bool is_time_dependent)
	Function to set whether this is a time-dependent function or not. More...
bool	is_time_dependent () const

Protected Attributes
const FunctionBase *	_master
	Const pointer to our master, initialized to nullptr. More...
bool	_initialized
	When init() was called so that everything is ready for calls to operator() (...), then this bool is true. More...
bool	_is_time_dependent
	Cache whether or not this function is actually time-dependent. More...

Private Attributes
std::vector< std::unique_ptr< FunctionBase< Output > > >	subfunctions
std::vector< std::vector< unsigned int > >	index_maps
std::vector< std::pair< unsigned int, unsigned int > >	reverse_index_map

Detailed Description

template<typename Output = Number>
class libMesh::CompositeFunction< Output >

A function that returns a vector whose components are defined by multiple functions.

A function which is defined by composing the result of different functions into a single vector. All overridden virtual functions are documented in function_base.h.

Author

Roy Stogner

Date

2012 Function which is a function of another function.

Definition at line 49 of file composite_function.h.

Constructor & Destructor Documentation

CompositeFunction() [1/3]

template<typename Output = Number>

libMesh::CompositeFunction< Output >::CompositeFunction ( )

explicitdefault

CompositeFunction() [2/3]

template<typename Output = Number>

libMesh::CompositeFunction< Output >::CompositeFunction ( CompositeFunction< Output > &&  )

default

This class can be default move constructed and assigned.

CompositeFunction() [3/3]

template<typename Output = Number>

libMesh::CompositeFunction< Output >::CompositeFunction ( const CompositeFunction< Output > &  )

delete

This class contains unique_ptr members so it can't be default copied or assigned.

~CompositeFunction()

template<typename Output = Number>

virtual libMesh::CompositeFunction< Output >::~CompositeFunction ( )

virtualdefault

The subfunctions vector is automatically cleaned up.

Member Function Documentation

attach_subfunction()

template<typename Output = Number>

void libMesh::CompositeFunction< Output >::attach_subfunction ( const FunctionBase< Output > &  f, std::vector< unsigned int >  index_map  )

inline

Attach a new subfunction, along with a map from the indices of the attached subfunction to the indices of the composed function.

The composed function will return a vector whose value at index index_map[i] is the value of the attached function at index i, i.e., (*this)(x, t)(index_map[i]) will return f(x, t)(i).

Definition at line 82 of file composite_function.h.

References libMesh::FunctionBase< Output >::_is_time_dependent, libMesh::FunctionBase< Output >::clone(), libMesh::CompositeFunction< Output >::index_maps, libMesh::index_range(), libMesh::invalid_uint, libMesh::FunctionBase< Output >::is_time_dependent(), libMesh::CompositeFunction< Output >::reverse_index_map, and libMesh::CompositeFunction< Output >::subfunctions.

Referenced by CompositeFunctionTest::testRemap(), and CompositeFunctionTest::testTimeDependence().

  {
    const unsigned int subfunction_index =
      cast_int<unsigned int>(subfunctions.size());
    libmesh_assert_equal_to(subfunctions.size(), index_maps.size());

    subfunctions.push_back(f.clone());

    unsigned int max_index =
      *std::max_element(index_map.begin(), index_map.end());

    if (max_index >= reverse_index_map.size())
      reverse_index_map.resize
        (max_index+1, std::make_pair(libMesh::invalid_uint,
                                     libMesh::invalid_uint));

    for (auto j : index_range(index_map))
      {
        libmesh_assert_less(index_map[j], reverse_index_map.size());
        libmesh_assert_equal_to(reverse_index_map[index_map[j]].first,
                                libMesh::invalid_uint);
        libmesh_assert_equal_to(reverse_index_map[index_map[j]].second,
                                libMesh::invalid_uint);
        reverse_index_map[index_map[j]] =
          std::make_pair(subfunction_index, j);
      }

    // Now check for time dependence
    // We only check the function we just added instead of researching all subfunctions
    // If this is the first subfunction, then that determines the time-dependence.
    if (subfunctions.size() == 1)
      this->_is_time_dependent = subfunctions[0]->is_time_dependent();

    // Otherwise, we have more than 1 function already.
    // If _is_time_dependent is true, then one of the previous
    // subfunctions is time-dependent and thus this CompositeFunction
    // time-dependent. If _is_time_dependent is false, then the subfunction
    // just added determines the time-dependence.
    else if (!this->_is_time_dependent)
      this->_is_time_dependent = (subfunctions.back())->is_time_dependent();

    index_maps.push_back(std::move(index_map));
  }

clear()

template<typename Output = Number>

virtual void libMesh::FunctionBase< Output >::clear ( )

inlinevirtualinherited

Clears the function.

Reimplemented in libMesh::ParsedFunction< Output, OutputGradient >, libMesh::ParsedFunction< T >, libMesh::MeshFunction, libMesh::AnalyticFunction< Output >, libMesh::MeshfreeInterpolationFunction, ExampleOneFunction, and ExampleOneFunction.

Definition at line 92 of file function_base.h.

{}

clone()

template<typename Output = Number>

virtual std::unique_ptr<FunctionBase<Output> > libMesh::CompositeFunction< Output >::clone ( ) const

inlineoverridevirtual

Returns

A new copy of the function.

The new copy should be as "deep" as necessary to allow independent destruction and simultaneous evaluations of the copies in different threads.

Implements libMesh::FunctionBase< Output >.

Definition at line 170 of file composite_function.h.

References libMesh::CompositeFunction< Output >::index_maps, libMesh::index_range(), and libMesh::CompositeFunction< Output >::subfunctions.

  {
    auto returnval = std::make_unique<CompositeFunction>();
    for (auto i : index_range(subfunctions))
      returnval->attach_subfunction(*subfunctions[i], index_maps[i]);
    return returnval;
  }

component()

template<typename Output = Number>

virtual Output libMesh::CompositeFunction< Output >::component ( unsigned int  i, const Point &  p, Real  time  )

inlineoverridevirtual

Returns

The vector component i at coordinate p and time time.

Note

Subclasses aren't required to override this, since the default implementation is based on the full vector evaluation, which is often correct.

Subclasses are recommended to override this, since the default implementation is based on a vector evaluation, which is usually unnecessarily inefficient.

The default implementation calls operator() with a DenseVector of size i+1 which will result in unexpected behaviour if operator() makes any access beyond that limit.

Reimplemented from libMesh::FunctionBase< Output >.

Definition at line 154 of file composite_function.h.

References libMesh::invalid_uint, libMesh::CompositeFunction< Output >::reverse_index_map, and libMesh::CompositeFunction< Output >::subfunctions.

Referenced by libMesh::CompositeFunction< Output >::operator()().

  {
    if (i >= reverse_index_map.size() ||
        reverse_index_map[i].first == libMesh::invalid_uint)
      return 0;

    libmesh_assert_less(reverse_index_map[i].first,
                        subfunctions.size());
    libmesh_assert_not_equal_to(reverse_index_map[i].second,
                                libMesh::invalid_uint);
    return subfunctions[reverse_index_map[i].first]->
      component(reverse_index_map[i].second,p,time);
  }

init()

template<typename Output = Number>

virtual void libMesh::FunctionBase< Output >::init ( )

inlinevirtualinherited

The actual initialization process.

Reimplemented in libMesh::ParsedFunction< Output, OutputGradient >, libMesh::ParsedFunction< T >, libMesh::MeshFunction, libMesh::AnalyticFunction< Output >, libMesh::GradientMeshFunction, libMesh::MeshfreeInterpolationFunction, ExampleOneFunction, and ExampleOneFunction.

Definition at line 87 of file function_base.h.

{}

initialized()

template<typename Output >

bool libMesh::FunctionBase< Output >::initialized ( ) const

inlineinherited

Returns

true when this object is properly initialized and ready for use, false otherwise.

Definition at line 210 of file function_base.h.

Referenced by libMesh::MeshFunction::MeshFunction().

{
  return (this->_initialized);
}

is_time_dependent()

template<typename Output >

bool libMesh::FunctionBase< Output >::is_time_dependent ( ) const

inlineinherited

Returns

true when the function this object represents is actually time-dependent, false otherwise.

Definition at line 224 of file function_base.h.

Referenced by libMesh::CompositeFunction< Output >::attach_subfunction(), CompositeFunctionTest::testTimeDependence(), and ParsedFunctionTest::testTimeDependence().

{
  return (this->_is_time_dependent);
}

n_components()

template<typename Output = Number>

unsigned int libMesh::CompositeFunction< Output >::n_components ( ) const

inline

Definition at line 183 of file composite_function.h.

References libMesh::CompositeFunction< Output >::reverse_index_map.

  {
    return reverse_index_map.size();
  }

n_subfunctions()

template<typename Output = Number>

unsigned int libMesh::CompositeFunction< Output >::n_subfunctions ( ) const

inline

Definition at line 178 of file composite_function.h.

References libMesh::CompositeFunction< Output >::subfunctions.

  {
    return subfunctions.size();
  }

operator()() [1/3]

template<typename Output>

void libMesh::FunctionBase< Output >::operator() ( const Point &  p, DenseVector< Output > &  output  )

inlineinherited

Evaluation function for time-independent vector-valued functions.

Sets output values in the passed-in output DenseVector.

Definition at line 245 of file function_base.h.

{
  // Call the time-dependent function with t=0.
  this->operator()(p, 0., output);
}

operator()() [2/3]

template<typename Output = Number>

virtual Output libMesh::CompositeFunction< Output >::operator() ( const Point &  p, const Real  time = 0  )

inlineoverridevirtual

Returns

The scalar function value at coordinate p and time time, which defaults to zero.

Pure virtual, so you have to override it.

Implements libMesh::FunctionBase< Output >.

Definition at line 127 of file composite_function.h.

References libMesh::CompositeFunction< Output >::component().

  {
    return this->component(0,p,time);
  }

operator()() [3/3]

template<typename Output = Number>

virtual void libMesh::CompositeFunction< Output >::operator() ( const Point &  p, const Real  time, DenseVector< Output > &  output  )

inlineoverridevirtual

Evaluation function for time-dependent vector-valued functions.

Sets output values in the passed-in output DenseVector.

Pure virtual, so you have to override it.

Implements libMesh::FunctionBase< Output >.

Definition at line 133 of file composite_function.h.

References libMesh::CompositeFunction< Output >::index_maps, libMesh::index_range(), libMesh::DenseVector< T >::resize(), libMesh::CompositeFunction< Output >::reverse_index_map, libMesh::DenseVector< T >::size(), libMesh::CompositeFunction< Output >::subfunctions, and libMesh::DenseVector< T >::zero().

  {
    libmesh_assert_greater_equal (output.size(),
                                  reverse_index_map.size());

    // Necessary in case we have output components not covered by
    // any subfunctions
    output.zero();

    DenseVector<Output> temp;
    for (auto i : index_range(subfunctions))
      {
        temp.resize(cast_int<unsigned int>(index_maps[i].size()));
        (*subfunctions[i])(p, time, temp);
        for (auto j : index_range(temp))
          output(index_maps[i][j]) = temp(j);
      }
  }

operator=() [1/2]

template<typename Output = Number>

CompositeFunction& libMesh::CompositeFunction< Output >::operator= ( CompositeFunction< Output > &&  )

default

operator=() [2/2]

template<typename Output = Number>

CompositeFunction& libMesh::CompositeFunction< Output >::operator= ( const CompositeFunction< Output > &  )

delete

set_is_time_dependent()

template<typename Output >

void libMesh::FunctionBase< Output >::set_is_time_dependent ( bool  is_time_dependent )

inlineinherited

Function to set whether this is a time-dependent function or not.

This is intended to be only used by subclasses who cannot natively determine time-dependence. In such a case, this function should be used immediately following construction.

Definition at line 217 of file function_base.h.

{
  this->_is_time_dependent = is_time_dependent;
}

Member Data Documentation

_initialized

template<typename Output = Number>

bool libMesh::FunctionBase< Output >::_initialized

protectedinherited

When init() was called so that everything is ready for calls to operator() (...), then this bool is true.

Definition at line 184 of file function_base.h.

Referenced by libMesh::AnalyticFunction< Output >::AnalyticFunction(), libMesh::ConstFunction< Output >::ConstFunction(), and libMesh::WrappedFunction< Output >::WrappedFunction().

_is_time_dependent

template<typename Output = Number>

bool libMesh::FunctionBase< Output >::_is_time_dependent

protectedinherited

Cache whether or not this function is actually time-dependent.

Definition at line 189 of file function_base.h.

Referenced by libMesh::CompositeFunction< Output >::attach_subfunction(), and libMesh::ConstFunction< Output >::ConstFunction().

_master

template<typename Output = Number>

const FunctionBase* libMesh::FunctionBase< Output >::_master

protectedinherited

Const pointer to our master, initialized to nullptr.

There may be cases where multiple functions are required, but to save memory, one master handles some centralized data.

Definition at line 178 of file function_base.h.

index_maps

template<typename Output = Number>

std::vector<std::vector<unsigned int> > libMesh::CompositeFunction< Output >::index_maps

private

Definition at line 193 of file composite_function.h.

Referenced by libMesh::CompositeFunction< Output >::attach_subfunction(), libMesh::CompositeFunction< Output >::clone(), and libMesh::CompositeFunction< Output >::operator()().

reverse_index_map

template<typename Output = Number>

std::vector<std::pair<unsigned int, unsigned int> > libMesh::CompositeFunction< Output >::reverse_index_map

private

Definition at line 196 of file composite_function.h.

Referenced by libMesh::CompositeFunction< Output >::attach_subfunction(), libMesh::CompositeFunction< Output >::component(), libMesh::CompositeFunction< Output >::n_components(), and libMesh::CompositeFunction< Output >::operator()().

subfunctions

template<typename Output = Number>

std::vector<std::unique_ptr<FunctionBase<Output> > > libMesh::CompositeFunction< Output >::subfunctions

private

Definition at line 190 of file composite_function.h.

Referenced by libMesh::CompositeFunction< Output >::attach_subfunction(), libMesh::CompositeFunction< Output >::clone(), libMesh::CompositeFunction< Output >::component(), libMesh::CompositeFunction< Output >::n_subfunctions(), and libMesh::CompositeFunction< Output >::operator()().

---

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

• include/numerics/composite_function.h