MaterialPropertyLib::Function Class Reference

Detailed Description

A function property defined by mathematical expression. For the evaluation of the expressions the exprtk library is used. In the expressions all variables defined in MaterialPropertyLib::Variable enum, t for time, x,y,z for the spatial position are supported, and curves from the <curves> section can be called using their names. A curve is a single argument function and can be used in an expression like curveA(sin(t)).

The evaluation is thread-safe for OpenMP by using per-thread storage.

Definition at line 29 of file Function.h.

#include <Function.h>

Inheritance diagram for MaterialPropertyLib::Function:

Collaboration diagram for MaterialPropertyLib::Function:

Classes
class	Implementation

Public Member Functions
	Function (std::string name, std::vector< std::string > const &value_string_expressions, std::vector< std::pair< std::string, std::vector< std::string > > > const &dvalue_string_expressions, std::map< std::string, std::unique_ptr< MathLib::PiecewiseLinearInterpolation > > const &curves)
PropertyDataType	value (VariableArray const &variable_array, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const override
PropertyDataType	dValue (VariableArray const &variable_array, Variable const variable, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const override
	~Function ()
Public Member Functions inherited from MaterialPropertyLib::Property
virtual	~Property ()
virtual PropertyDataType	initialValue (ParameterLib::SpatialPosition const &pos, double const t) const
virtual PropertyDataType	value () const
virtual PropertyDataType	value (VariableArray const &variable_array, VariableArray const &variable_array_prev, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const
virtual PropertyDataType	dValue (VariableArray const &variable_array, VariableArray const &variable_array_prev, Variable const variable, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const
virtual PropertyDataType	d2Value (VariableArray const &variable_array, Variable const variable1, Variable const variable2, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const
	Default implementation: 2nd derivative of any constant property is zero.
virtual void	setProperties (std::vector< std::unique_ptr< Phase > > const &phases)
	Default implementation:
void	setScale (std::variant< Medium *, Phase *, Component * > scale)
template<typename T>
T	initialValue (ParameterLib::SpatialPosition const &pos, double const t) const
template<typename T>
T	value () const
template<typename T>
T	value (VariableArray const &variable_array, VariableArray const &variable_array_prev, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const
template<typename T>
T	value (VariableArray const &variable_array, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const
template<typename T>
T	dValue (VariableArray const &variable_array, VariableArray const &variable_array_prev, Variable const variable, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const
template<typename T>
T	dValue (VariableArray const &variable_array, Variable const variable, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const
template<typename T>
T	d2Value (VariableArray const &variable_array, Variable const &variable1, Variable const &variable2, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const

Private Member Functions
std::variant< Function::Implementation< 2 > *, Function::Implementation< 3 > * >	getImplementationForDimensionOfVariableArray (VariableArray const &variable_array) const

Private Attributes
std::unique_ptr< Implementation< 2 > >	impl2_
std::unique_ptr< Implementation< 3 > >	impl3_
std::vector< Variable >	variables_
	Variables used in the exprtk expressions.

Additional Inherited Members
Protected Attributes inherited from MaterialPropertyLib::Property
std::string	name_
PropertyDataType	value_
	The single value of a property.
PropertyDataType	dvalue_
std::variant< Medium *, Phase *, Component * >	scale_

Constructor & Destructor Documentation

Function()

MaterialPropertyLib::Function::Function	(	std::string	name,
		std::vector< std::string > const &	value_string_expressions,
		std::vector< std::pair< std::string, std::vector< std::string > > > const &	dvalue_string_expressions,
		std::map< std::string, std::unique_ptr< MathLib::PiecewiseLinearInterpolation > > const &	curves )

Definition at line 458 of file Function.cpp.

{
    name_ = std::move(name);
 
    auto const variables =
        collectVariables(value_string_expressions, dvalue_string_expressions);
 
    // filter the strings unrelated to time or spatial position
    static std::unordered_set<std::string> filter_not_variables = {"t", "x",
                                                                   "y", "z"};
    for (auto const& curve : curves)
    {
        filter_not_variables.insert(curve.first);
    }
 
    variables_ =
        variables |
        std::views::filter([](const std::string& s)
                           { return !filter_not_variables.contains(s); }) |
        std::views::transform([](std::string const& s)
                              { return convertStringToVariable(s); }) |
        ranges::to<std::vector>;
 
    auto const get_number_omp_threads = []()
    {
#ifdef _OPENMP
        return omp_get_max_threads();
#else
        return 1;
#endif
    };
 
    int const num_threads = std::max(BaseLib::getNumberOfAssemblyThreads(),
                                     get_number_omp_threads());
 
    impl2_ = std::make_unique<Implementation<2>>(
        num_threads, variables, value_string_expressions,
        dvalue_string_expressions, curves);
    impl3_ = std::make_unique<Implementation<3>>(
        num_threads, variables, value_string_expressions,
        dvalue_string_expressions, curves);
}

References MaterialPropertyLib::collectVariables(), MaterialPropertyLib::convertStringToVariable(), BaseLib::getNumberOfAssemblyThreads(), impl2_, impl3_, MaterialPropertyLib::name, MaterialPropertyLib::Property::name_, and variables_.

~Function()

MaterialPropertyLib::Function::~Function ( )

default

Member Function Documentation

dValue()

PropertyDataType MaterialPropertyLib::Function::dValue ( VariableArray const & variable_array, Variable const variable, ParameterLib::SpatialPosition const & pos, double const t, double const dt ) const

overridevirtual

This virtual method will compute the property derivative value based on the variables that are passed as arguments with the default implementation using empty variables array for the previous time step.

The default implementation of this method only returns the property value derivative without altering it.

Reimplemented from MaterialPropertyLib::Property.

Definition at line 555 of file Function.cpp.

{
#ifdef _OPENMP
    int const thread_id = omp_get_thread_num();
#else
    int const thread_id = 0;
#endif
    return std::visit(
        [&](auto&& impl_ptr)
        {
            if (thread_id >=
                static_cast<int>(impl_ptr->dvalue_expressions.size()))
            {
                OGS_FATAL(
                    "In Function-type property '{:s}' evaluation the "
                    "OMP-thread with id {:d} exceeds the number of allocated "
                    "threads {:d}.",
                    name_, thread_id, impl_ptr->value_expressions.size());
            }
            auto const it = std::find_if(
                begin(impl_ptr->dvalue_expressions[thread_id]),
                end(impl_ptr->dvalue_expressions[thread_id]),
                [&variable](auto const& v) { return v.first == variable; });
 
            if (it == end(impl_ptr->dvalue_expressions[thread_id]))
            {
                OGS_FATAL(
                    "Requested derivative with respect to the variable {:s} "
                    "not "
                    "provided for Function-type property {:s}.",
                    variable_enum_to_string[static_cast<int>(variable)], name_);
            }
 
            return evaluateExpressions(variables_, variable_array, pos, t,
                                       it->second,
                                       impl_ptr->variable_arrays[thread_id],
                                       impl_ptr->spatial_position_is_required);
        },
        getImplementationForDimensionOfVariableArray(variable_array));
}

References MaterialPropertyLib::evaluateExpressions(), getImplementationForDimensionOfVariableArray(), MaterialPropertyLib::Property::name_, OGS_FATAL, MaterialPropertyLib::variable_enum_to_string, and variables_.

getImplementationForDimensionOfVariableArray()

std::variant< Function::Implementation< 2 > *, Function::Implementation< 3 > * > MaterialPropertyLib::Function::getImplementationForDimensionOfVariableArray ( VariableArray const & variable_array ) const

private

Definition at line 509 of file Function.cpp.

{
    if (variable_array.is2D())
    {
        return impl2_.get();
    }
    if (variable_array.is3D())
    {
        return impl3_.get();
    }
 
    OGS_FATAL(
        "Variable array has vectors for 2 and 3 dimensions simultaneously. "
        "Mixed dimensions cannot be dealt within Function evaluation.");
}

References impl2_, impl3_, MaterialPropertyLib::VariableArray::is2D(), MaterialPropertyLib::VariableArray::is3D(), and OGS_FATAL.

Referenced by dValue(), and value().

value()

PropertyDataType MaterialPropertyLib::Function::value ( VariableArray const & variable_array, ParameterLib::SpatialPosition const & pos, double const t, double const dt ) const

overridevirtual

This virtual method will compute the property value based on the variables that are passed as arguments with the default implementation using empty variables array for the previous time step.

Reimplemented from MaterialPropertyLib::Property.

Definition at line 526 of file Function.cpp.

{
#ifdef _OPENMP
    int const thread_id = omp_get_thread_num();
#else
    int const thread_id = 0;
#endif
    return std::visit(
        [&](auto&& impl_ptr)
        {
            if (thread_id >=
                static_cast<int>(impl_ptr->value_expressions.size()))
            {
                OGS_FATAL(
                    "In Function-type property '{:s}' evaluation the "
                    "OMP-thread with id {:d} exceeds the number of allocated "
                    "threads {:d}.",
                    name_, thread_id, impl_ptr->value_expressions.size());
            }
            return evaluateExpressions(variables_, variable_array, pos, t,
                                       impl_ptr->value_expressions[thread_id],
                                       impl_ptr->variable_arrays[thread_id],
                                       impl_ptr->spatial_position_is_required);
        },
        getImplementationForDimensionOfVariableArray(variable_array));
}

References MaterialPropertyLib::evaluateExpressions(), getImplementationForDimensionOfVariableArray(), MaterialPropertyLib::Property::name_, OGS_FATAL, and variables_.

Referenced by MaterialPropertyLib::Function::Implementation< D >::createSymbolTable().

Member Data Documentation

impl2_

std::unique_ptr<Implementation<2> > MaterialPropertyLib::Function::impl2_

private

Definition at line 58 of file Function.h.

Referenced by Function(), and getImplementationForDimensionOfVariableArray().

impl3_

std::unique_ptr<Implementation<3> > MaterialPropertyLib::Function::impl3_

private

Definition at line 59 of file Function.h.

Referenced by Function(), and getImplementationForDimensionOfVariableArray().

variables_

std::vector<Variable> MaterialPropertyLib::Function::variables_

private

Variables used in the exprtk expressions.

Definition at line 66 of file Function.h.

Referenced by Function(), dValue(), and value().

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

• MaterialLib/MPL/Properties/Function.h
• MaterialLib/MPL/Properties/Function.cpp