smats::ExpressionAdd< T > Class Template Reference

#include <expression_cell.h>

Inheritance diagram for smats::ExpressionAdd< T >:

Public Types
using	ExpressionMap = std::map<Expression<T>, T>

Public Member Functions
	NEW_OPERATOR_PARAMS (ExpressionAdd, PARAMS(T constant, ExpressionMap expr_to_coeff_map), PARAMS(constant, expr_to_coeff_map))
void	hash (DelegatingHasher &) const override
bool	equal_to (const ExpressionCell< T > &o) const override
bool	less (const ExpressionCell< T > &o) const override
T	evaluate (const Environment< T > &env) const override
Expression< T >	evaluate_partial (const Environment< T > &env) const override
Expression< T >	expand () const override
Expression< T >	substitute (const Substitution< T > &s) const override
Expression< T >	differentiate (const Variable &x) const override
std::ostream &	display (std::ostream &os) const override
const T &	constant () const
T &	m_constant ()
const ExpressionMap &	expr_to_coeff_map () const
ExpressionMap &	m_expr_to_coeff_map ()
Public Member Functions inherited from smats::ExpressionCell< T >
long	use_count () const
ExpressionKind	kind () const
const Variables &	variables () const
bool	is_polynomial () const
bool	is_expanded () const
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
void	invalidate_cache ()

Static Public Attributes
static const ExpressionKind	expression_kind = ExpressionKind::Add

Private Member Functions
void	compute_variables (std::optional< Variables > &variables) const override
void	compute_is_polynomial (std::optional< bool > &is_polynomial) const override
std::ostream &	display_term (std::ostream &os, bool print_plus, const T &coeff, const Expression< T > &term) const

Static Private Member Functions
static Variables	extract_variables (const ExpressionMap &expr_to_coeff_map)

Private Attributes
const T	constant_
	Constant term of the addition.
const ExpressionMap	expr_to_coeff_map_
	Map from expressions to their coefficients.

Additional Inherited Members
Protected Member Functions inherited from smats::ExpressionCell< T >
	ExpressionCell (ExpressionKind kind, bool is_expanded)
	ExpressionCell (ExpressionKind kind, bool is_polynomial, bool is_expanded)

Detailed Description

template<class T>
class smats::ExpressionAdd< T >

Symbolic expression representing the addition of multiple terms.

The expression holds a constant term and a map from expressions to their coefficients. Let \( k \) be the constant term and \( E \) be the set of pairs \((c, e)\) where \( c \) is the coefficient and \( e \) is the expression. The ExpressionAdd cell represents the following expression:

\[ k + \sum_{(c, e) \in E} c \cdot e \]

Template Parameters

T	type of the expression evaluation

Member Function Documentation

compute_is_polynomial()

template<class T >

void smats::ExpressionAdd< T >::compute_is_polynomial ( std::optional< bool > & is_polynomial ) const

overrideprivatevirtual

Implements smats::ExpressionCell< T >.

compute_variables()

template<class T >

void smats::ExpressionAdd< T >::compute_variables ( std::optional< Variables > & variables ) const

overrideprivatevirtual

Implements smats::ExpressionCell< T >.

constant()

template<class T >

const T & smats::ExpressionAdd< T >::constant ( ) const

inlinenodiscard

Get read-only access to the constant of the addition expression.

Returns

constant of the addition expression

differentiate()

template<class T >

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

nodiscardoverridevirtual

Differentiates this symbolic expression with respect to the variable var.

Parameters

x

variable

Exceptions

std::runtime_exception

if it is not differentiable.

Implements smats::ExpressionCell< T >.

display()

template<class T >

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

overridevirtual

Displays the expression in a human-readable format.

Parameters

os	output stream

Returns

updated output stream

Implements smats::ExpressionCell< T >.

display_term()

template<class T >

std::ostream & smats::ExpressionAdd< T >::display_term ( std::ostream & os, bool print_plus, const T & coeff, const Expression< T > & term ) const

private

Utility function used to display a single term in a pretty format.

Parameters

os	output stream
print_plus	whether to print a plus at the beginning
coeff	coefficient of the term
term	expression of the term

Returns

updated output stream

equal_to()

template<class T >

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

nodiscardoverridevirtual

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

Implements smats::ExpressionCell< T >.

evaluate()

template<class T >

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

nodiscardoverridevirtual

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

Parameters

env	environment

Exceptions

std::runtime_exception

if NaN is detected during evaluation.

Implements smats::ExpressionCell< T >.

evaluate_partial()

template<class T >

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

nodiscardoverridevirtual

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.

Implements smats::ExpressionCell< T >.

expand()

template<class T >

Expression< T > smats::ExpressionAdd< T >::expand ( ) const

nodiscardoverridevirtual

Expands out products and positive integer powers in expression.

Exceptions

std::runtime_exception

if NaN is detected during expansion.

Implements smats::ExpressionCell< T >.

expr_to_coeff_map()

template<class T >

const ExpressionMap & smats::ExpressionAdd< T >::expr_to_coeff_map ( ) const

inlinenodiscard

Get read-only access to the map of the addition expression.

Returns

map of the addition expression

hash()

template<class T >

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

overridevirtual

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.

Implements smats::ExpressionCell< T >.

less()

template<class T >

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

nodiscardoverridevirtual

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

Implements smats::ExpressionCell< T >.

m_constant()

template<class T >

T & smats::ExpressionAdd< T >::m_constant

(

)

Get read-write access to the constant of the addition expression.

Returns

constant of the addition expression

m_expr_to_coeff_map()

template<class T >

ExpressionAdd< T >::ExpressionMap & smats::ExpressionAdd< T >::m_expr_to_coeff_map

(

)

Get read-write access to the map of the addition expression.

Returns

map of the addition expression

substitute()

template<class T >

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

nodiscardoverridevirtual

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.

Implements smats::ExpressionCell< T >.

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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