Nektar::LibUtilities::Equation Class Reference

#include <Equation.h>

Public Member Functions
	Equation (const Equation &)=default
	Equation ()
	Equation (InterpreterSharedPtr evaluator, const std::string &expr="", const std::string &vlist="")
Equation &	operator= (const Equation &src)
NekDouble	Evaluate () const
NekDouble	Evaluate (NekDouble x, NekDouble y=0, NekDouble z=0, NekDouble t=0) const
NekDouble	Evaluate (std::vector< NekDouble > point) const
void	Evaluate (const Array< OneD, const NekDouble > &x, const Array< OneD, const NekDouble > &y, const Array< OneD, const NekDouble > &z, Array< OneD, NekDouble > &result) const
void	Evaluate (const Array< OneD, const NekDouble > &x, const Array< OneD, const NekDouble > &y, const Array< OneD, const NekDouble > &z, const NekDouble t, Array< OneD, NekDouble > &result) const
void	Evaluate (const Array< OneD, const NekDouble > &x, const Array< OneD, const NekDouble > &y, const Array< OneD, const NekDouble > &z, const Array< OneD, const NekDouble > &t, Array< OneD, NekDouble > &result) const
void	Evaluate (const std::vector< Array< OneD, const NekDouble > > points, Array< OneD, NekDouble > &result) const
void	SetParameter (const std::string &name, NekDouble value)
void	SetConstants (const std::map< std::string, NekDouble > &constants)
std::string	GetExpression (void) const
std::string	GetVlist (void) const
NekDouble	GetTime () const
	Returns time spend on expression evaluation at points (it does not include parse/pre-processing time).

Private Attributes
std::string	m_vlist
std::string	m_expr
int	m_expr_id
InterpreterSharedPtr	m_evaluator

Detailed Description

This class stores a string form of a symbolic expression to be evaluated e.g. for the boundary conditions, the unique numeric ID of that expression and a reference to the unique static instance of the Interpreter.

The scenario is that for multiple copies of Equation class holding their symbolic expressions in the std::string form, there is a unique instance of Interpreter, which holds a set of pre-processed symbolic expressions in the form of sequential containers of execution functors, ready for fast evaluation.

The interpreter also keeps all constants and parameters specified in an XML file. There should be only one copy of Equation class per each symbolic expression specified in XML file, modulo possible bugs. Classes Equation and Interpreter are complementary in a sense that the expression ID stored in the Equation class is generated by the Interpreter which holds ordered container of pre-processed expressions.

Definition at line 67 of file Equation.h.

Constructor & Destructor Documentation

Equation() [1/3]

Nektar::LibUtilities::Equation::Equation ( const Equation &  )

default

Equation() [2/3]

Nektar::LibUtilities::Equation::Equation

(

)

Definition at line 46 of file BasicUtils/Equation.cpp.

{
    // Create Null expression and vlist
    m_expr  = "0.0";
    m_vlist = "x y z t";
    boost::algorithm::trim(m_expr);
    boost::algorithm::trim(m_vlist);
 
    // Evaluate expression
    m_evaluator = MemoryManager<Interpreter>::AllocateSharedPtr();
    m_expr_id   = m_evaluator->DefineFunction(m_vlist, m_expr);
}

References Nektar::MemoryManager< DataType >::AllocateSharedPtr(), m_evaluator, m_expr, m_expr_id, and m_vlist.

Equation() [3/3]

Nektar::LibUtilities::Equation::Equation	(	InterpreterSharedPtr	evaluator,
		const std::string &	expr = "",
		const std::string &	vlist = ""
	)

Definition at line 59 of file BasicUtils/Equation.cpp.

    : m_vlist(vlist), m_expr(expr), m_expr_id(-1), m_evaluator(evaluator)
{
    boost::algorithm::trim(m_expr);
    boost::algorithm::trim(m_vlist);
 
    if (m_vlist.empty())
    {
        m_vlist = "x y z t";
    }
 
    try
    {
        if (!m_expr.empty())
        {
            m_expr_id = m_evaluator->DefineFunction(m_vlist, m_expr);
        }
    }
    catch (const std::runtime_error &e)
    {
        m_expr_id = -1;
        std::string msg(
            std::string("Equation::Equation() fails on expression [") + m_expr +
            std::string("]\n"));
        NEKERROR(ErrorUtil::efatal, msg);
        throw e;
        return;
    }
    catch (const std::string &e)
    {
        m_expr_id = -1;
        std::string msg(
            std::string("Equation::Equation() fails on expression [") + m_expr +
            std::string("]\n"));
        NEKERROR(ErrorUtil::efatal, msg);
        throw e;
        return;
    }
}

References Nektar::ErrorUtil::efatal, m_evaluator, m_expr, m_expr_id, m_vlist, and NEKERROR.

Member Function Documentation

Evaluate() [1/7]

NekDouble Nektar::LibUtilities::Equation::Evaluate

(

)

const

Definition at line 109 of file BasicUtils/Equation.cpp.

{
    try
    {
        if (m_expr_id != -1)
        {
            return m_evaluator->Evaluate(m_expr_id);
        }
    }
    catch (const std::runtime_error &e)
    {
        std::string msg(
            std::string("Equation::Evaluate fails on expression [") + m_expr +
            std::string("]\n"));
        NEKERROR(ErrorUtil::efatal, msg + std::string("ERROR: ") + e.what());
    }
    catch (const std::string &e)
    {
        std::string msg(
            std::string("Equation::Evaluate fails on expression [") + m_expr +
            std::string("]\n"));
        NEKERROR(ErrorUtil::efatal, msg + std::string("ERROR: ") + e);
    }
    return 0;
}

References Nektar::ErrorUtil::efatal, m_evaluator, m_expr, m_expr_id, and NEKERROR.

Referenced by Evaluate(), Evaluate(), Evaluate(), Nektar::SolverUtils::ForcingMovingReferenceFrame::EvaluateExpression(), Nektar::SolverUtils::FilterAeroForces::FilterAeroForces(), Nektar::FilterAeroForcesSPM::FilterAeroForcesSPM(), Nektar::SolverUtils::FilterAverageFields::FilterAverageFields(), Nektar::FilterBenchmark::FilterBenchmark(), Nektar::SolverUtils::FilterBodyFittedVelocity::FilterBodyFittedVelocity(), Nektar::SolverUtils::FilterCheckpoint::FilterCheckpoint(), Nektar::FilterCheckpointCellModel::FilterCheckpointCellModel(), Nektar::FilterElectrogram::FilterElectrogram(), Nektar::SolverUtils::FilterEnergy::FilterEnergy(), Nektar::SolverUtils::FilterEnergy1D::FilterEnergy1D(), Nektar::SolverUtils::FilterError::FilterError(), Nektar::SolverUtils::FilterFieldConvert::FilterFieldConvert(), Nektar::FilterHilbertFFTPhase::FilterHilbertFFTPhase(), Nektar::SolverUtils::FilterHistoryPoints::FilterHistoryPoints(), Nektar::SolverUtils::FilterIntegral::FilterIntegral(), Nektar::SolverUtils::FilterMaxMinFields::FilterMaxMinFields(), Nektar::SolverUtils::FilterMean::FilterMean(), Nektar::SolverUtils::FilterModalEnergy::FilterModalEnergy(), Nektar::SolverUtils::FilterMovingAverage::FilterMovingAverage(), Nektar::FilterMovingBody::FilterMovingBody(), Nektar::FilterOffsetPhase::FilterOffsetPhase(), Nektar::SolverUtils::FilterReynoldsStresses::FilterReynoldsStresses(), Nektar::SolverUtils::FilterThresholdMax::FilterThresholdMax(), Nektar::SolverUtils::FilterThresholdMin::FilterThresholdMin(), Nektar::SpatialDomains::MeshGraph::ReadExpansionInfo(), Nektar::LibUtilities::SessionReader::ReadParameters(), Nektar::SpatialDomains::MeshGraph::ReadRefinementInfo(), and Nektar::SolverUtils::FilterLagrangianPoints::v_Initialise().

Evaluate() [2/7]

void Nektar::LibUtilities::Equation::Evaluate	(	const Array< OneD, const NekDouble > &	x,
		const Array< OneD, const NekDouble > &	y,
		const Array< OneD, const NekDouble > &	z,
		Array< OneD, NekDouble > &	result
	)		const

Definition at line 186 of file BasicUtils/Equation.cpp.

{
    Array<OneD, NekDouble> zero(x.size(), 0.0);
    Evaluate(x, y, z, zero, result);
}

References Evaluate().

Evaluate() [3/7]

void Nektar::LibUtilities::Equation::Evaluate	(	const Array< OneD, const NekDouble > &	x,
		const Array< OneD, const NekDouble > &	y,
		const Array< OneD, const NekDouble > &	z,
		const Array< OneD, const NekDouble > &	t,
		Array< OneD, NekDouble > &	result
	)		const

Definition at line 204 of file BasicUtils/Equation.cpp.

{
    std::vector<Array<OneD, const NekDouble>> points;
    points.push_back(x);
    points.push_back(y);
    points.push_back(z);
    points.push_back(t);
    Evaluate(points, result);
}

References Evaluate().

Evaluate() [4/7]

void Nektar::LibUtilities::Equation::Evaluate	(	const Array< OneD, const NekDouble > &	x,
		const Array< OneD, const NekDouble > &	y,
		const Array< OneD, const NekDouble > &	z,
		const NekDouble	t,
		Array< OneD, NekDouble > &	result
	)		const

Definition at line 195 of file BasicUtils/Equation.cpp.

{
    Array<OneD, NekDouble> time(x.size(), t);
    Evaluate(x, y, z, time, result);
}

References Evaluate().

Evaluate() [5/7]

void Nektar::LibUtilities::Equation::Evaluate	(	const std::vector< Array< OneD, const NekDouble > >	points,
		Array< OneD, NekDouble > &	result
	)		const

Definition at line 218 of file BasicUtils/Equation.cpp.

{
    try
    {
        if (m_expr_id != -1)
        {
            m_evaluator->Evaluate(m_expr_id, points, result);
        }
    }
    catch (const std::runtime_error &e)
    {
        std::string msg =
            "Equation::Evaluate fails on expression [" + m_expr + "]\n";
        NEKERROR(ErrorUtil::efatal, msg + std::string("ERROR: ") + e.what());
        return;
    }
    catch (const std::string &e)
    {
        std::string msg =
            "Equation::Evaluate fails on expression [" + m_expr + "]\n";
        NEKERROR(ErrorUtil::efatal, msg + std::string("ERROR: ") + e);
        return;
    }
}

References Nektar::ErrorUtil::efatal, m_evaluator, m_expr, m_expr_id, and NEKERROR.

Evaluate() [6/7]

NekDouble Nektar::LibUtilities::Equation::Evaluate	(	NekDouble	x,
		NekDouble	y = 0,
		NekDouble	z = 0,
		NekDouble	t = 0
	)		const

Definition at line 135 of file BasicUtils/Equation.cpp.

{
    try
    {
        if (m_expr_id != -1)
        {
            return m_evaluator->Evaluate(m_expr_id, x, y, z, t);
        }
    }
    catch (const std::runtime_error &e)
    {
        std::string msg =
            "Equation::Evaluate fails on expression [" + m_expr + "]\n";
        NEKERROR(ErrorUtil::efatal, msg + std::string("ERROR: ") + e.what());
    }
    catch (const std::string &e)
    {
        std::string msg =
            "Equation::Evaluate fails on expression [" + m_expr + "]\n";
        NEKERROR(ErrorUtil::efatal, msg + std::string("ERROR: ") + e);
    }
 
    return 0;
}

References Nektar::ErrorUtil::efatal, m_evaluator, m_expr, m_expr_id, and NEKERROR.

Evaluate() [7/7]

NekDouble Nektar::LibUtilities::Equation::Evaluate

(

std::vector< NekDouble >

point

)

const

Definition at line 161 of file BasicUtils/Equation.cpp.

{
    try
    {
        if (m_expr_id != -1)
        {
            return m_evaluator->EvaluateAtPoint(m_expr_id, point);
        }
    }
    catch (const std::runtime_error &e)
    {
        std::string msg =
            "Equation::Evaluate fails on expression [" + m_expr + "]\n";
        NEKERROR(ErrorUtil::efatal, msg + std::string("ERROR: ") + e.what());
    }
    catch (const std::string &e)
    {
        std::string msg =
            "Equation::Evaluate fails on expression [" + m_expr + "]\n";
        NEKERROR(ErrorUtil::efatal, msg + std::string("ERROR: ") + e);
    }
 
    return 0;
}

References Nektar::ErrorUtil::efatal, m_evaluator, m_expr, m_expr_id, and NEKERROR.

GetExpression()

std::string Nektar::LibUtilities::Equation::GetExpression

(

void

)

const

Definition at line 254 of file BasicUtils/Equation.cpp.

{
    return m_expr;
}

References m_expr.

Referenced by export_Equation().

GetTime()

NekDouble Nektar::LibUtilities::Equation::GetTime

(

)

const

Returns time spend on expression evaluation at points (it does not include parse/pre-processing time).

Definition at line 266 of file BasicUtils/Equation.cpp.

{
    return m_evaluator->GetTime();
}

References m_evaluator.

Referenced by export_Equation().

GetVlist()

std::string Nektar::LibUtilities::Equation::GetVlist

(

void

)

const

Definition at line 259 of file BasicUtils/Equation.cpp.

{
    return m_vlist;
}

References m_vlist.

Referenced by export_Equation().

operator=()

Equation & Nektar::LibUtilities::Equation::operator=

(

const Equation &

src

)

Definition at line 100 of file BasicUtils/Equation.cpp.

{
    m_vlist     = src.m_vlist;
    m_expr      = src.m_expr;
    m_expr_id   = src.m_expr_id;
    m_evaluator = src.m_evaluator;
    return *this;
}

References m_evaluator, m_expr, m_expr_id, and m_vlist.

SetConstants()

void Nektar::LibUtilities::Equation::SetConstants

(

const std::map< std::string, NekDouble > &

constants

)

Definition at line 249 of file BasicUtils/Equation.cpp.

{
    m_evaluator->AddConstants(constants);
}

References m_evaluator.

SetParameter()

void Nektar::LibUtilities::Equation::SetParameter	(	const std::string &	name,
		NekDouble	value
	)

Definition at line 244 of file BasicUtils/Equation.cpp.

{
    m_evaluator->SetParameter(name, value);
}

References m_evaluator.

Referenced by export_Equation().

Member Data Documentation

m_evaluator

InterpreterSharedPtr Nektar::LibUtilities::Equation::m_evaluator

private

Definition at line 128 of file Equation.h.

Referenced by Equation(), Equation(), Evaluate(), Evaluate(), Evaluate(), Evaluate(), GetTime(), operator=(), SetConstants(), and SetParameter().

m_expr

std::string Nektar::LibUtilities::Equation::m_expr

private

Definition at line 126 of file Equation.h.

Referenced by Equation(), Equation(), Evaluate(), Evaluate(), Evaluate(), Evaluate(), GetExpression(), and operator=().

m_expr_id

int Nektar::LibUtilities::Equation::m_expr_id

private

Definition at line 127 of file Equation.h.

Referenced by Equation(), Equation(), Evaluate(), Evaluate(), Evaluate(), Evaluate(), and operator=().

m_vlist

std::string Nektar::LibUtilities::Equation::m_vlist

private

Definition at line 125 of file Equation.h.

Referenced by Equation(), Equation(), GetVlist(), and operator=().