libMesh::MeshTools::Generation::Private::GaussLobattoRedistributionFunction Class Reference

This object is passed to MeshTools::Modification::redistribute() to redistribute the points on a uniform grid into the Gauss-Lobatto points on the actual grid. More...

Inheritance diagram for libMesh::MeshTools::Generation::Private::GaussLobattoRedistributionFunction:

Public Member Functions
	GaussLobattoRedistributionFunction (unsigned int nx, Real xmin, Real xmax, unsigned int ny=0, Real ymin=0, Real ymax=0, unsigned int nz=0, Real zmin=0, Real zmax=0)
	Constructor. More...
	GaussLobattoRedistributionFunction (GaussLobattoRedistributionFunction &&)=default
	The 5 special functions can be defaulted for this class. More...
	GaussLobattoRedistributionFunction (const GaussLobattoRedistributionFunction &)=default
GaussLobattoRedistributionFunction &	operator= (const GaussLobattoRedistributionFunction &)=default
GaussLobattoRedistributionFunction &	operator= (GaussLobattoRedistributionFunction &&)=default
virtual	~GaussLobattoRedistributionFunction ()=default
virtual std::unique_ptr< FunctionBase< Real > >	clone () const override
	We must provide a way to clone ourselves to satisfy the pure virtual interface. More...
virtual void	operator() (const Point &p, const Real, DenseVector< Real > &output) override
	This is the actual function that MeshTools::Modification::redistribute() calls. More...
virtual Real	operator() (const Point &, const Real) override
	We must also override operator() which returns a Real, but this function should never be called, so it's left unimplemented. More...
virtual void	init ()
	The actual initialization process. More...
virtual void	clear ()
	Clears the function. More...
void	operator() (const Point &p, DenseVector< Real > &output)
	Evaluation function for time-independent vector-valued functions. More...
virtual Real	component (unsigned int i, const Point &p, Real time=0.)
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
std::vector< Real >	_mins
std::vector< unsigned int >	_nelem
std::vector< Real >	_widths
std::vector< std::vector< Real > >	_cosines
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...

Detailed Description

This object is passed to MeshTools::Modification::redistribute() to redistribute the points on a uniform grid into the Gauss-Lobatto points on the actual grid.

Definition at line 159 of file mesh_generation.C.

Constructor & Destructor Documentation

GaussLobattoRedistributionFunction() [1/3]

libMesh::MeshTools::Generation::Private::GaussLobattoRedistributionFunction::GaussLobattoRedistributionFunction ( unsigned int  nx, Real  xmin, Real  xmax, unsigned int  ny = 0, Real  ymin = 0, Real  ymax = 0, unsigned int  nz = 0, Real  zmin = 0, Real  zmax = 0  )

inline

Constructor.

Definition at line 165 of file mesh_generation.C.

References _cosines, _mins, _nelem, _widths, libMesh::index_range(), libMesh::pi, and libMesh::Real.

                                                  :
    FunctionBase<Real>(nullptr)
  {
    _nelem.resize(3);
    _nelem[0] = nx;
    _nelem[1] = ny;
    _nelem[2] = nz;

    _mins.resize(3);
    _mins[0] = xmin;
    _mins[1] = ymin;
    _mins[2] = zmin;

    _widths.resize(3);
    _widths[0] = xmax - xmin;
    _widths[1] = ymax - ymin;
    _widths[2] = zmax - zmin;

    // Precompute the cosine values.
    _cosines.resize(3);
    for (unsigned dir=0; dir<3; ++dir)
      if (_nelem[dir] != 0)
        {
          _cosines[dir].resize(_nelem[dir]+1);
          for (auto i : index_range(_cosines[dir]))
            _cosines[dir][i] = std::cos(libMesh::pi * Real(i) / _nelem[dir]);
        }
  }

GaussLobattoRedistributionFunction() [2/3]

libMesh::MeshTools::Generation::Private::GaussLobattoRedistributionFunction::GaussLobattoRedistributionFunction ( GaussLobattoRedistributionFunction &&  )

default

The 5 special functions can be defaulted for this class.

GaussLobattoRedistributionFunction() [3/3]

libMesh::MeshTools::Generation::Private::GaussLobattoRedistributionFunction::GaussLobattoRedistributionFunction ( const GaussLobattoRedistributionFunction &  )

default

~GaussLobattoRedistributionFunction()

virtual libMesh::MeshTools::Generation::Private::GaussLobattoRedistributionFunction::~GaussLobattoRedistributionFunction ( )

virtualdefault

Member Function Documentation

clear()

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

inlinevirtualinherited

Clears the function.

Definition at line 92 of file function_base.h.

{}

clone()

virtual std::unique_ptr<FunctionBase<Real> > libMesh::MeshTools::Generation::Private::GaussLobattoRedistributionFunction::clone ( ) const

inlineoverridevirtual

We must provide a way to clone ourselves to satisfy the pure virtual interface.

We use the autogenerated copy constructor.

Implements libMesh::FunctionBase< Real >.

Definition at line 215 of file mesh_generation.C.

  {
    return std::make_unique<GaussLobattoRedistributionFunction>(*this);
  }

component()

Real libMesh::FunctionBase< Real >::component ( unsigned int  i, const Point &  p, Real  time = 0.  )

inlinevirtualinherited

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.

Definition at line 232 of file function_base.h.

{
  DenseVector<Output> outvec(i+1);
  (*this)(p, time, outvec);
  return outvec(i);
}

init()

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

inlinevirtualinherited

The actual initialization process.

Definition at line 87 of file function_base.h.

{}

initialized()

bool libMesh::FunctionBase< Real >::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.

{
  return (this->_initialized);
}

is_time_dependent()

bool libMesh::FunctionBase< Real >::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.

{
  return (this->_is_time_dependent);
}

operator()() [1/3]

void libMesh::FunctionBase< Real >::operator() ( const Point &  p, DenseVector< Real > &  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]

virtual void libMesh::MeshTools::Generation::Private::GaussLobattoRedistributionFunction::operator() ( const Point &  p, const Real  , DenseVector< Real > &  output  )

inlineoverridevirtual

This is the actual function that MeshTools::Modification::redistribute() calls.

Moves the points of the grid to the Gauss-Lobatto points.

Implements libMesh::FunctionBase< Real >.

Definition at line 225 of file mesh_generation.C.

References _cosines, _mins, _nelem, _widths, std::abs(), int, libMesh::Real, libMesh::DenseVector< T >::resize(), and libMesh::TOLERANCE.

  {
    output.resize(3);

    for (unsigned dir=0; dir<3; ++dir)
      if (_nelem[dir] != 0)
        {
          // Figure out the index of the current point.
          Real float_index = (p(dir) - _mins[dir]) * _nelem[dir] / _widths[dir];

          // std::modf separates the fractional and integer parts of the index.
          Real integer_part_f = 0;
          const Real fractional_part = std::modf(float_index, &integer_part_f);

          const int integer_part = int(integer_part_f);

          // Vertex node?
          if (std::abs(fractional_part) < TOLERANCE || std::abs(fractional_part - 1.0) < TOLERANCE)
            {
              int index = int(round(float_index));

              // Move node to the Gauss-Lobatto position.
              output(dir) = _mins[dir] + _widths[dir] * 0.5 * (1.0 - _cosines[dir][index]);
            }

          // Mid-edge (quadratic) node?
          else if (std::abs(fractional_part - 0.5) < TOLERANCE)
            {
              // Move node to the Gauss-Lobatto position, which is the average of
              // the node to the left and the node to the right.
              output(dir) = _mins[dir] + _widths[dir] * 0.5 *
                (1.0 - 0.5*(_cosines[dir][integer_part] + _cosines[dir][integer_part+1]));
            }

          // 1D only: Left interior (cubic) node?
          else if (std::abs(fractional_part - 1./3.) < TOLERANCE)
            {
              // Move node to the Gauss-Lobatto position, which is
              // 2/3*left_vertex + 1/3*right_vertex.
              output(dir) = _mins[dir] + _widths[dir] * 0.5 *
                (1.0 - 2./3.*_cosines[dir][integer_part] - 1./3.*_cosines[dir][integer_part+1]);
            }

          // 1D only: Right interior (cubic) node?
          else if (std::abs(fractional_part - 2./3.) < TOLERANCE)
            {
              // Move node to the Gauss-Lobatto position, which is
              // 1/3*left_vertex + 2/3*right_vertex.
              output(dir) = _mins[dir] + _widths[dir] * 0.5 *
                (1.0 - 1./3.*_cosines[dir][integer_part] - 2./3.*_cosines[dir][integer_part+1]);
            }

          else
            libmesh_error_msg("Cannot redistribute node: " << p);
        }
  }

operator()() [3/3]

virtual Real libMesh::MeshTools::Generation::Private::GaussLobattoRedistributionFunction::operator() ( const Point &  , const Real    )

inlineoverridevirtual

We must also override operator() which returns a Real, but this function should never be called, so it's left unimplemented.

Implements libMesh::FunctionBase< Real >.

Definition at line 288 of file mesh_generation.C.

  {
    libmesh_not_implemented();
  }

operator=() [1/2]

GaussLobattoRedistributionFunction& libMesh::MeshTools::Generation::Private::GaussLobattoRedistributionFunction::operator= ( const GaussLobattoRedistributionFunction &  )

default

operator=() [2/2]

GaussLobattoRedistributionFunction& libMesh::MeshTools::Generation::Private::GaussLobattoRedistributionFunction::operator= ( GaussLobattoRedistributionFunction &&  )

default

set_is_time_dependent()

void libMesh::FunctionBase< Real >::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

_cosines

std::vector<std::vector<Real> > libMesh::MeshTools::Generation::Private::GaussLobattoRedistributionFunction::_cosines

protected

Definition at line 301 of file mesh_generation.C.

Referenced by GaussLobattoRedistributionFunction(), and operator()().

_initialized

bool libMesh::FunctionBase< Real >::_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.

_is_time_dependent

bool libMesh::FunctionBase< Real >::_is_time_dependent

protectedinherited

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

Definition at line 189 of file function_base.h.

_master

const FunctionBase* libMesh::FunctionBase< Real >::_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.

_mins

std::vector<Real> libMesh::MeshTools::Generation::Private::GaussLobattoRedistributionFunction::_mins

protected

Definition at line 296 of file mesh_generation.C.

Referenced by GaussLobattoRedistributionFunction(), and operator()().

_nelem

std::vector<unsigned int> libMesh::MeshTools::Generation::Private::GaussLobattoRedistributionFunction::_nelem

protected

Definition at line 297 of file mesh_generation.C.

Referenced by GaussLobattoRedistributionFunction(), and operator()().

_widths

std::vector<Real> libMesh::MeshTools::Generation::Private::GaussLobattoRedistributionFunction::_widths

protected

Definition at line 298 of file mesh_generation.C.

Referenced by GaussLobattoRedistributionFunction(), and operator()().

---

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

• src/mesh/mesh_generation.C