#include <expression_cell.h>

Inheritance diagram for smats::ExpressionCell< T >:

Classes
struct	Private

Public Member Functions
long	use_count () const

ExpressionKind	kind () const

virtual void	hash (DelegatingHasher &) const =0

const Variables &	variables () const

bool	is_polynomial () const

bool	is_expanded () const

virtual bool	equal_to (const ExpressionCell< T > &o) const =0

virtual bool	less (const ExpressionCell< T > &o) const =0

void	set_expanded ()

template<template< class > class E>
const E< T > &	to () const

template<template< class > class E>
E< T > &	to ()

Expression< T >	to_expression () const

virtual T	evaluate (const Environment< T > &env) const =0

virtual Expression< T >	expand () const =0

virtual Expression< T >	evaluate_partial (const Environment< T > &env) const =0

virtual Expression< T >	substitute (const Substitution< T > &s) const =0

virtual Expression< T >	differentiate (const Variable &x) const =0

virtual std::ostream &	display (std::ostream &os) const =0

void	invalidate_cache ()

Protected Member Functions
	ExpressionCell (ExpressionKind kind, bool is_expanded)

	ExpressionCell (ExpressionKind kind, bool is_polynomial, bool is_expanded)

virtual void	compute_variables (std::optional< Variables > &variables) const =0

virtual void	compute_is_polynomial (std::optional< bool > &is_polynomial) const =0

Private Attributes
const ExpressionKind	kind_
	The kind of the expression.

std::optional< Variables >	variables_
	Cached variables in the expression.

std::optional< bool >	is_polynomial_
	Cached information about whether the expression is a polynomial.

bool	is_expanded_ {false}
	Whether the expression is already expanded.

Detailed Description

template<class T>
class smats::ExpressionCell< T >

Abstract class used as the base of concrete symbolic-expression classes.

Note: It provides virtual function, ExpressionCell<T>::display because operator<< is not allowed to be virtual.; All subclasses of ExpressionCell must be immutable and implement the static function
static std::shared_ptr<ExpressionCell> create() { return std::make_shared<ExpressionCell>(Private()); }

smats::ExpressionCell::Private
Definition expression_cell.h:179

to create instances of the ExpressionCell externally while guaranteeing the use of shared_ptr.

Template Parameters

T	type of the expression evaluation

Constructor & Destructor Documentation

◆ ExpressionCell() [1/2]

template<class T >

smats::ExpressionCell< T >::ExpressionCell	(	ExpressionKind	kind,
		bool	is_expanded )

protected

Constructs ExpressionCell of kind with is_expanded .

Parameters

kind	kind of the expression
is_expanded	whether the expression is already expanded

ExpressionCell

◆ ExpressionCell() [2/2]

template<class T >

smats::ExpressionCell< T >::ExpressionCell	(	ExpressionKind	kind,
		bool	is_polynomial,
		bool	is_expanded )

protected

Constructs ExpressionCell of kind with is_polynomial and is_expanded .

Parameters

kind	kind of the expression
is_polynomial	whether the expression is a polynomial
is_expanded	whether the expression is already expanded

Member Function Documentation

◆ differentiate()

template<class T >

virtual Expression< T > smats::ExpressionCell< T >::differentiate ( const Variable & x ) const

nodiscardpure virtual

Differentiates this symbolic expression with respect to the variable var.

Parameters

x variable

Exceptions

std::runtime_exception if it is not differentiable.

Implemented in smats::ExpressionAdd< T >, smats::ExpressionConstant< T >, smats::ExpressionDiv< T >, smats::ExpressionMul< T >, smats::ExpressionNaN< T >, smats::ExpressionPow< T >, and smats::ExpressionVar< T >.

◆ display()

template<class T >

virtual std::ostream & smats::ExpressionCell< T >::display ( std::ostream & os ) const

pure virtual

Displays the expression in a human-readable format.

Parameters

os	output stream

Returns: updated output stream

Implemented in smats::ExpressionAdd< T >, smats::ExpressionConstant< T >, smats::ExpressionDiv< T >, smats::ExpressionMul< T >, smats::ExpressionNaN< T >, smats::ExpressionPow< T >, and smats::ExpressionVar< T >.

◆ equal_to()

template<class T >

virtual bool smats::ExpressionCell< T >::equal_to ( const ExpressionCell< T > & o ) const

nodiscardpure virtual

Compare two expression cells to determine if they are equal.

Parameters

o	other object to compare against

Returns: true the two object are equal; false if the two objects are different

Implemented in smats::BinaryExpressionCell< T >, smats::ExpressionAdd< T >, smats::ExpressionConstant< T >, smats::ExpressionMul< T >, smats::ExpressionNaN< T >, and smats::ExpressionVar< T >.

◆ evaluate()

template<class T >

virtual T smats::ExpressionCell< T >::evaluate ( const Environment< T > & env ) const

nodiscardpure virtual

Evaluates under a given environment (by default, an empty environment).

Parameters

env	environment

Exceptions

std::runtime_exception if NaN is detected during evaluation.

Implemented in smats::BinaryExpressionCell< T >, smats::ExpressionAdd< T >, smats::ExpressionConstant< T >, smats::ExpressionMul< T >, smats::ExpressionNaN< T >, and smats::ExpressionVar< T >.

◆ evaluate_partial()

template<class T >

virtual Expression< T > smats::ExpressionCell< T >::evaluate_partial ( const Environment< T > & env ) const

nodiscardpure virtual

Returns an Expression obtained by replacing all occurrences of the variables in env in the current expression cell with the corresponding values in env.

Parameters

env	environment

Exceptions

std::runtime_exception if NaN is detected during substitution.

Implemented in smats::ExpressionAdd< T >, smats::ExpressionConstant< T >, smats::ExpressionDiv< T >, smats::ExpressionMul< T >, smats::ExpressionNaN< T >, smats::ExpressionPow< T >, and smats::ExpressionVar< T >.

◆ expand()

template<class T >

virtual Expression< T > smats::ExpressionCell< T >::expand ( ) const

nodiscardpure virtual

Expands out products and positive integer powers in expression.

Exceptions

std::runtime_exception if NaN is detected during expansion.

Implemented in smats::ExpressionAdd< T >, smats::ExpressionConstant< T >, smats::ExpressionDiv< T >, smats::ExpressionMul< T >, smats::ExpressionNaN< T >, smats::ExpressionPow< T >, and smats::ExpressionVar< T >.

◆ hash()

template<class T >

virtual void smats::ExpressionCell< T >::hash ( DelegatingHasher & ) const

pure virtual

Sends all hash-relevant bytes for this ExpressionCell type into the given hasher, per the hash_append concept, except for kind(), because Expression already sends that.

Implemented in smats::BinaryExpressionCell< T >, smats::ExpressionAdd< T >, smats::ExpressionConstant< T >, smats::ExpressionMul< T >, smats::ExpressionNaN< T >, and smats::ExpressionVar< T >.

◆ invalidate_cache()

template<class T >

void smats::ExpressionCell< T >::invalidate_cache ( )

Invalidate the cached information.

This will force the expression to recompute the cached information the next time they are requested. Must be called whenever the expression is modified.

◆ is_expanded()

template<class T >

bool smats::ExpressionCell< T >::is_expanded ( ) const

inlinenodiscard

Check whether the expression cell is expanded.

Returns: true if the expression cell is expanded; false if the expression cell is not expanded

◆ is_polynomial()

template<class T >

bool smats::ExpressionCell< T >::is_polynomial ( ) const

nodiscard

Check whether the expression cell is polynomial.

Returns: true if the expression cell is polynomial; false if the expression cell is not polynomial

◆ kind()

template<class T >

ExpressionKind smats::ExpressionCell< T >::kind ( ) const

inlinenodiscard

Get read-only access to the kind of the expression cell.

Returns: kind of the expression cell

◆ less()

template<class T >

virtual bool smats::ExpressionCell< T >::less ( const ExpressionCell< T > & o ) const

nodiscardpure virtual

Compare two expression cells to determine the order between them.

Parameters

o	other object to compare against

Returns: true if this object is less than the other object; false if this object is not less than the other object

Implemented in smats::BinaryExpressionCell< T >, smats::ExpressionAdd< T >, smats::ExpressionConstant< T >, smats::ExpressionMul< T >, smats::ExpressionNaN< T >, and smats::ExpressionVar< T >.

◆ set_expanded()

template<class T >

void smats::ExpressionCell< T >::set_expanded ( )

inline

Sets this symbolic expression as already expanded.

◆ substitute()

template<class T >

virtual Expression< T > smats::ExpressionCell< T >::substitute ( const Substitution< T > & s ) const

nodiscardpure virtual

Returns an Expression obtained by replacing all occurrences of the variables in s in the current expression cell with the corresponding expressions in s.

Parameters

s	substitution

Exceptions

std::runtime_exception if NaN is detected during substitution.

Implemented in smats::ExpressionAdd< T >, smats::ExpressionConstant< T >, smats::ExpressionDiv< T >, smats::ExpressionMul< T >, smats::ExpressionNaN< T >, smats::ExpressionPow< T >, and smats::ExpressionVar< T >.

◆ to() [1/2]

template<class T >

template<template< class > class E>

E< T > & smats::ExpressionCell< T >::to ( )

inlinenodiscard

Casts this ExpressionCell to a subclass of ExpressionCell with the same template type.

Template Parameters

E	subclass of ExpressionCell

Returns: mutable reference to the casted ExpressionCell

◆ to() [2/2]

template<class T >

template<template< class > class E>

const E< T > & smats::ExpressionCell< T >::to ( ) const

inlinenodiscard

Casts this ExpressionCell to a subclass of ExpressionCell with the same template type.

Template Parameters

E	subclass of ExpressionCell

Returns: constant reference to the casted ExpressionCell

◆ to_expression()

template<class T >

Expression< T > smats::ExpressionCell< T >::to_expression ( ) const

inlinenodiscard

Create an Expression from this ExpressionCell.

Returns: Expression containing this ExpressionCell

◆ use_count()

template<class T >

long smats::ExpressionCell< T >::use_count ( ) const

inlinenodiscard

Get read-only access to the reference count of the expression cell.

Returns: reference count of the expression cell

◆ variables()

template<class T >

const Variables & smats::ExpressionCell< T >::variables ( ) const

nodiscard

Get read-only access to the variables of the expression cell.

Returns: variables of the expression cell

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

smats/symbolic/expression.h
smats/symbolic/expression_cell.h
smats/symbolic/expression_cell.cpp

Classes

Public Member Functions

Protected Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ ExpressionCell() [1/2]

◆ ExpressionCell() [2/2]

Member Function Documentation

◆ differentiate()

◆ display()

◆ equal_to()

◆ evaluate()

◆ evaluate_partial()

◆ expand()

◆ hash()

◆ invalidate_cache()

◆ is_expanded()

◆ is_polynomial()

◆ kind()

◆ less()

◆ set_expanded()

◆ substitute()

◆ to() [1/2]

◆ to() [2/2]

◆ to_expression()

◆ use_count()

◆ variables()