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 can be used.

Warning

The evaluation calls are not to be used in parallel (openMP), because the values' updates are using the same space.

Definition at line 26 of file Function.h.

#include <Function.h>

Inheritance diagram for MaterialPropertyLib::Function:

Collaboration diagram for MaterialPropertyLib::Function:

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)
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 primary_variable, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const override
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. More...
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 Types
using	Expression = exprtk::expression< double >

Private Attributes
std::vector< std::pair< int, double * > >	symbol_values_
	Mapping from variable array index to symbol table values. More...
std::vector< Expression >	value_expressions_
std::vector< std::pair< Variable, std::vector< Expression > > >	dvalue_expressions_

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

Member Typedef Documentation

Expression

using MaterialPropertyLib::Function::Expression = exprtk::expression<double>

private

Definition at line 47 of file Function.h.

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
	)

Definition at line 151 of file Function.cpp.

{
    name_ = std::move(name);
 
    // Create symbol table for used variables.
    exprtk::symbol_table<double> symbol_table;
 
    for (auto const& v :
         collectVariables(value_string_expressions, dvalue_string_expressions))
    {
        symbol_table.create_variable(v);
        // Store variables index in the variable array and the pointer to the
        // value in the symbol table for fast access later.
        int const variable_array_index =
            static_cast<int>(convertStringToVariable(v));
        symbol_values_.emplace_back(variable_array_index,
                                    &symbol_table.get_variable(v)->ref());
    }
 
    // value expressions.
    value_expressions_ =
        compileExpressions(symbol_table, value_string_expressions);
 
    // dValue expressions.
    for (auto const& [variable_name, string_expressions] :
         dvalue_string_expressions)
    {
        dvalue_expressions_.emplace_back(
            convertStringToVariable(variable_name),
            compileExpressions(symbol_table, string_expressions));
    }
}

References MaterialPropertyLib::collectVariables(), MaterialPropertyLib::compileExpressions(), MaterialPropertyLib::convertStringToVariable(), dvalue_expressions_, MaterialPropertyLib::name, MaterialPropertyLib::Property::name_, symbol_values_, and value_expressions_.

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 196 of file Function.cpp.

{
    auto const it = std::find_if(begin(dvalue_expressions_),
                                 end(dvalue_expressions_),
                                 [&primary_variable](auto const& v)
                                 { return v.first == primary_variable; });
 
    if (it == end(dvalue_expressions_))
    {
        OGS_FATAL(
            "Requested derivative with respect to the variable {:s} not "
            "provided for Function-type property {:s}.",
            variable_enum_to_string[static_cast<int>(primary_variable)], name_);
    }
 
    return evaluateExpressions(symbol_values_, variable_array, it->second);
}

References dvalue_expressions_, MaterialPropertyLib::evaluateExpressions(), MaterialPropertyLib::Property::name_, OGS_FATAL, symbol_values_, and MaterialPropertyLib::variable_enum_to_string.

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 188 of file Function.cpp.

{
    return evaluateExpressions(symbol_values_, variable_array,
                               value_expressions_);
}

References MaterialPropertyLib::evaluateExpressions(), symbol_values_, and value_expressions_.

Member Data Documentation

dvalue_expressions_

std::vector<std::pair<Variable, std::vector<Expression> > > MaterialPropertyLib::Function::dvalue_expressions_

private

Derivative expressions with respect to the variable. Multiple expressions are representing vector-valued functions.

Definition at line 57 of file Function.h.

Referenced by Function(), and dValue().

symbol_values_

std::vector<std::pair<int, double*> > MaterialPropertyLib::Function::symbol_values_

private

Mapping from variable array index to symbol table values.

Definition at line 50 of file Function.h.

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

value_expressions_

std::vector<Expression> MaterialPropertyLib::Function::value_expressions_

private

Value expressions. Multiple expressions are representing vector-valued functions.

Definition at line 53 of file Function.h.

Referenced by Function(), 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