sleipnir::detail::Expression Struct Reference

#include <sleipnir/autodiff/Expression.hpp>

Inheritance diagram for sleipnir::detail::Expression:

Public Member Functions
constexpr	Expression ()=default
constexpr	Expression (double value)
constexpr	Expression (ExpressionPtr lhs)
constexpr	Expression (ExpressionPtr lhs, ExpressionPtr rhs)
virtual	~Expression ()=default
constexpr bool	IsConstant (double constant) const
virtual double	Value (double lhs, double rhs) const =0
virtual ExpressionType	Type () const =0
virtual double	GradientValueLhs (double lhs, double rhs, double parentAdjoint) const
virtual double	GradientValueRhs (double lhs, double rhs, double parentAdjoint) const
virtual ExpressionPtr	GradientLhs (const ExpressionPtr &lhs, const ExpressionPtr &rhs, const ExpressionPtr &parentAdjoint) const
virtual ExpressionPtr	GradientRhs (const ExpressionPtr &lhs, const ExpressionPtr &rhs, const ExpressionPtr &parentAdjoint) const

Public Attributes
double	value = 0.0
	The value of the expression node.
double	adjoint = 0.0
	The adjoint of the expression node used during autodiff.
uint32_t	duplications = 0
int32_t	row = -1
ExpressionPtr	adjointExpr
uint32_t	refCount = 0
	Reference count for intrusive shared pointer.
std::array< ExpressionPtr, 2 >	args {nullptr, nullptr}
	Expression arguments.

Friends
ExpressionPtr	operator* (const ExpressionPtr &lhs, const ExpressionPtr &rhs)
ExpressionPtr	operator/ (const ExpressionPtr &lhs, const ExpressionPtr &rhs)
ExpressionPtr	operator+ (const ExpressionPtr &lhs, const ExpressionPtr &rhs)
ExpressionPtr	operator- (const ExpressionPtr &lhs, const ExpressionPtr &rhs)
ExpressionPtr	operator- (const ExpressionPtr &lhs)
ExpressionPtr	operator+ (const ExpressionPtr &lhs)

Detailed Description

An autodiff expression node.

Constructor & Destructor Documentation

Expression() [1/4]

constexpr sleipnir::detail::Expression::Expression ( )

constexprdefault

Constructs a constant expression with a value of zero.

Expression() [2/4]

constexpr sleipnir::detail::Expression::Expression ( double  value )

inlineexplicitconstexpr

Constructs a nullary expression (an operator with no arguments).

Parameters

value

The expression value.

Expression() [3/4]

constexpr sleipnir::detail::Expression::Expression ( ExpressionPtr  lhs )

inlineexplicitconstexpr

Constructs an unary expression (an operator with one argument).

Parameters

lhs	Unary operator's operand.

Expression() [4/4]

constexpr sleipnir::detail::Expression::Expression ( ExpressionPtr  lhs, ExpressionPtr  rhs  )

inlineconstexpr

Constructs a binary expression (an operator with two arguments).

Parameters

lhs	Binary operator's left operand.
rhs	Binary operator's right operand.

~Expression()

virtual sleipnir::detail::Expression::~Expression ( )

virtualdefault

Member Function Documentation

GradientLhs()

virtual ExpressionPtr sleipnir::detail::Expression::GradientLhs ( const ExpressionPtr &  lhs, const ExpressionPtr &  rhs, const ExpressionPtr &  parentAdjoint  ) const

inlinevirtual

Returns Variable adjoint of the left child expression.

Parameters

lhs	Left argument to binary operator.
rhs	Right argument to binary operator.
parentAdjoint	Adjoint of parent expression.

Reimplemented in sleipnir::detail::SignExpression, sleipnir::detail::BinaryMinusExpression< T >, sleipnir::detail::BinaryPlusExpression< T >, sleipnir::detail::UnaryMinusExpression< T >, sleipnir::detail::DivExpression< T >, sleipnir::detail::PowExpression< T >, sleipnir::detail::MultExpression< T >, sleipnir::detail::AbsExpression, sleipnir::detail::AcosExpression, sleipnir::detail::AsinExpression, sleipnir::detail::AtanExpression, sleipnir::detail::CosExpression, sleipnir::detail::CoshExpression, sleipnir::detail::ErfExpression, sleipnir::detail::ExpExpression, sleipnir::detail::LogExpression, sleipnir::detail::Log10Expression, sleipnir::detail::SinExpression, sleipnir::detail::SinhExpression, sleipnir::detail::SqrtExpression, sleipnir::detail::TanExpression, sleipnir::detail::TanhExpression, sleipnir::detail::HypotExpression, and sleipnir::detail::Atan2Expression.

GradientRhs()

virtual ExpressionPtr sleipnir::detail::Expression::GradientRhs ( const ExpressionPtr &  lhs, const ExpressionPtr &  rhs, const ExpressionPtr &  parentAdjoint  ) const

inlinevirtual

Returns Variable adjoint of the right child expression.

Parameters

lhs	Left argument to binary operator.
rhs	Right argument to binary operator.
parentAdjoint	Adjoint of parent expression.

Reimplemented in sleipnir::detail::BinaryMinusExpression< T >, sleipnir::detail::BinaryPlusExpression< T >, sleipnir::detail::PowExpression< T >, sleipnir::detail::DivExpression< T >, sleipnir::detail::MultExpression< T >, sleipnir::detail::HypotExpression, and sleipnir::detail::Atan2Expression.

GradientValueLhs()

virtual double sleipnir::detail::Expression::GradientValueLhs ( double  lhs, double  rhs, double  parentAdjoint  ) const

inlinevirtual

Returns double adjoint of the left child expression.

Parameters

lhs	Left argument to binary operator.
rhs	Right argument to binary operator.
parentAdjoint	Adjoint of parent expression.

Reimplemented in sleipnir::detail::PowExpression< T >, sleipnir::detail::MultExpression< T >, sleipnir::detail::HypotExpression, sleipnir::detail::AbsExpression, sleipnir::detail::AcosExpression, sleipnir::detail::AsinExpression, sleipnir::detail::AtanExpression, sleipnir::detail::CosExpression, sleipnir::detail::CoshExpression, sleipnir::detail::ErfExpression, sleipnir::detail::ExpExpression, sleipnir::detail::LogExpression, sleipnir::detail::Log10Expression, sleipnir::detail::SinExpression, sleipnir::detail::SinhExpression, sleipnir::detail::SqrtExpression, sleipnir::detail::TanExpression, sleipnir::detail::TanhExpression, sleipnir::detail::Atan2Expression, sleipnir::detail::DivExpression< T >, sleipnir::detail::BinaryMinusExpression< T >, sleipnir::detail::BinaryPlusExpression< T >, sleipnir::detail::UnaryMinusExpression< T >, and sleipnir::detail::SignExpression.

GradientValueRhs()

virtual double sleipnir::detail::Expression::GradientValueRhs ( double  lhs, double  rhs, double  parentAdjoint  ) const

inlinevirtual

Returns double adjoint of the right child expression.

Parameters

lhs	Left argument to binary operator.
rhs	Right argument to binary operator.
parentAdjoint	Adjoint of parent expression.

Reimplemented in sleipnir::detail::PowExpression< T >, sleipnir::detail::DivExpression< T >, sleipnir::detail::MultExpression< T >, sleipnir::detail::HypotExpression, sleipnir::detail::Atan2Expression, sleipnir::detail::BinaryMinusExpression< T >, and sleipnir::detail::BinaryPlusExpression< T >.

IsConstant()

constexpr bool sleipnir::detail::Expression::IsConstant ( double  constant ) const

inlineconstexpr

Returns true if the expression is the given constant.

Parameters

constant

The constant.

Type()

virtual ExpressionType sleipnir::detail::Expression::Type ( ) const

pure virtual

Returns the type of this expression (constant, linear, quadratic, or nonlinear).

Implemented in sleipnir::detail::BinaryMinusExpression< T >, sleipnir::detail::BinaryPlusExpression< T >, sleipnir::detail::ConstExpression, sleipnir::detail::DecisionVariableExpression, sleipnir::detail::DivExpression< T >, sleipnir::detail::MultExpression< T >, sleipnir::detail::UnaryMinusExpression< T >, sleipnir::detail::AbsExpression, sleipnir::detail::AcosExpression, sleipnir::detail::AsinExpression, sleipnir::detail::AtanExpression, sleipnir::detail::Atan2Expression, sleipnir::detail::CosExpression, sleipnir::detail::CoshExpression, sleipnir::detail::ErfExpression, sleipnir::detail::ExpExpression, sleipnir::detail::HypotExpression, sleipnir::detail::LogExpression, sleipnir::detail::Log10Expression, sleipnir::detail::PowExpression< T >, sleipnir::detail::SignExpression, sleipnir::detail::SinExpression, sleipnir::detail::SinhExpression, sleipnir::detail::SqrtExpression, sleipnir::detail::TanExpression, and sleipnir::detail::TanhExpression.

Value()

virtual double sleipnir::detail::Expression::Value ( double  lhs, double  rhs  ) const

pure virtual

Either nullary operator with no arguments, unary operator with one argument, or binary operator with two arguments. This operator is used to update the node's value.

Parameters

lhs	Left argument to binary operator.
rhs	Right argument to binary operator.

Implemented in sleipnir::detail::PowExpression< T >, sleipnir::detail::BinaryMinusExpression< T >, sleipnir::detail::BinaryPlusExpression< T >, sleipnir::detail::DivExpression< T >, sleipnir::detail::MultExpression< T >, sleipnir::detail::UnaryMinusExpression< T >, sleipnir::detail::HypotExpression, sleipnir::detail::AbsExpression, sleipnir::detail::AcosExpression, sleipnir::detail::AsinExpression, sleipnir::detail::AtanExpression, sleipnir::detail::CosExpression, sleipnir::detail::CoshExpression, sleipnir::detail::ErfExpression, sleipnir::detail::ExpExpression, sleipnir::detail::LogExpression, sleipnir::detail::Log10Expression, sleipnir::detail::SignExpression, sleipnir::detail::SinExpression, sleipnir::detail::SinhExpression, sleipnir::detail::SqrtExpression, sleipnir::detail::TanExpression, sleipnir::detail::TanhExpression, sleipnir::detail::Atan2Expression, sleipnir::detail::ConstExpression, and sleipnir::detail::DecisionVariableExpression.

Friends And Related Symbol Documentation

operator*

ExpressionPtr operator* ( const ExpressionPtr &  lhs, const ExpressionPtr &  rhs  )

friend

Expression-Expression multiplication operator.

Parameters

lhs	Operator left-hand side.
rhs	Operator right-hand side.

operator+ [1/2]

ExpressionPtr operator+ ( const ExpressionPtr &  lhs )

friend

Unary plus operator.

Parameters

lhs	Operand of unary plus.

operator+ [2/2]

ExpressionPtr operator+ ( const ExpressionPtr &  lhs, const ExpressionPtr &  rhs  )

friend

Expression-Expression addition operator.

Parameters

lhs	Operator left-hand side.
rhs	Operator right-hand side.

operator- [1/2]

ExpressionPtr operator- ( const ExpressionPtr &  lhs )

friend

Unary minus operator.

Parameters

lhs	Operand of unary minus.

operator- [2/2]

ExpressionPtr operator- ( const ExpressionPtr &  lhs, const ExpressionPtr &  rhs  )

friend

Expression-Expression subtraction operator.

Parameters

lhs	Operator left-hand side.
rhs	Operator right-hand side.

operator/

ExpressionPtr operator/ ( const ExpressionPtr &  lhs, const ExpressionPtr &  rhs  )

friend

Expression-Expression division operator.

Parameters

lhs	Operator left-hand side.
rhs	Operator right-hand side.

Member Data Documentation

adjoint

double sleipnir::detail::Expression::adjoint = 0.0

The adjoint of the expression node used during autodiff.

adjointExpr

ExpressionPtr sleipnir::detail::Expression::adjointExpr

The adjoint of the expression node used during gradient expression tree generation.

args

std::array<ExpressionPtr, 2> sleipnir::detail::Expression::args {nullptr, nullptr}

Expression arguments.

duplications

uint32_t sleipnir::detail::Expression::duplications = 0

Tracks the number of instances of this expression yet to be encountered in an expression tree.

refCount

uint32_t sleipnir::detail::Expression::refCount = 0

Reference count for intrusive shared pointer.

row

int32_t sleipnir::detail::Expression::row = -1

This expression's row in wrt for autodiff gradient, Jacobian, or Hessian. This is -1 if the expression isn't in wrt.

value

double sleipnir::detail::Expression::value = 0.0

The value of the expression node.

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The documentation for this struct was generated from the following file:

• include/sleipnir/autodiff/Expression.hpp