gtsam::Expression< T > Class Template Reference

Detailed Description

template<typename T>
class gtsam::Expression< T >

Expression class that supports automatic differentiation.

Inheritance diagram for gtsam::Expression< T >:

Public Member Functions
	Expression (const T &value)
	Construct a constant expression.
	Expression (const Key &key)
	Construct a leaf expression, with Key.
	Expression (const Symbol &symbol)
	Construct a leaf expression, with Symbol.
	Expression (unsigned char c, std::uint64_t j)
	Construct a leaf expression, creating Symbol.
template<typename A >
	Expression (typename UnaryFunction< A >::type function, const Expression< A > &expression)
	Construct a unary function expression.
template<typename A1 , typename A2 >
	Expression (typename BinaryFunction< A1, A2 >::type function, const Expression< A1 > &expression1, const Expression< A2 > &expression2)
	Construct a binary function expression.
template<typename A1 , typename A2 , typename A3 >
	Expression (typename TernaryFunction< A1, A2, A3 >::type function, const Expression< A1 > &expression1, const Expression< A2 > &expression2, const Expression< A3 > &expression3)
	Construct a ternary function expression.
template<typename A >
	Expression (const Expression< A > &expression, T(A::*method)(typename MakeOptionalJacobian< T, A >::type) const)
	Construct a nullary method expression.
template<typename A1 , typename A2 >
	Expression (const Expression< A1 > &expression1, T(A1::*method)(const A2 &, typename MakeOptionalJacobian< T, A1 >::type, typename MakeOptionalJacobian< T, A2 >::type) const, const Expression< A2 > &expression2)
	Construct a unary method expression.
template<typename A1 , typename A2 , typename A3 >
	Expression (const Expression< A1 > &expression1, T(A1::*method)(const A2 &, const A3 &, typename MakeOptionalJacobian< T, A1 >::type, typename MakeOptionalJacobian< T, A2 >::type, typename MakeOptionalJacobian< T, A3 >::type) const, const Expression< A2 > &expression2, const Expression< A3 > &expression3)
	Construct a binary method expression.
virtual	~Expression ()
	Destructor.
std::set< Key >	keys () const
	Return keys that play in this expression.
void	dims (std::map< Key, int > &map) const
	Return dimensions for each argument, as a map.
void	print (const std::string &s) const
	Print.
T	value (const Values &values, boost::optional< std::vector< Matrix > & > H=boost::none) const
	Return value and optional derivatives, reverse AD version Notes: this is not terribly efficient, and H should have correct size. More...
virtual boost::shared_ptr< Expression >	clone () const
const boost::shared_ptr< internal::ExpressionNode< T > > &	root () const
	Return root.
size_t	traceSize () const
	Return size needed for memory buffer in traceExecution.
Expression< T > &	operator+= (const Expression< T > &e)
	Add another expression to this expression.

Public Types
typedef Expression< T >	type
	Define type so we can apply it as a meta-function.

Classes
struct	BinaryFunction
struct	TernaryFunction
struct	UnaryFunction

Protected Types
typedef std::pair< KeyVector, FastVector< int > >	KeysAndDims
	Keys and dimensions in same order.

Protected Member Functions
	Expression (const boost::shared_ptr< internal::ExpressionNode< T > > &root)
	Construct with a custom root.
	Expression ()
	Default constructor, for serialization.
KeysAndDims	keysAndDims () const
T	valueAndDerivatives (const Values &values, const KeyVector &keys, const FastVector< int > &dims, std::vector< Matrix > &H) const
	private version that takes keys and dimensions, returns derivatives
T	traceExecution (const Values &values, internal::ExecutionTrace< T > &trace, void *traceStorage) const
	trace execution, very unsafe
T	valueAndJacobianMap (const Values &values, internal::JacobianMap &jacobians) const
	brief Return value and derivatives, reverse AD version

Protected Attributes
boost::shared_ptr< internal::ExpressionNode< T > >	root_

Friends
class	ExpressionFactor< T >
class	internal::ExpressionNode< T >
class	::ExpressionFactorShallowTest

Member Function Documentation

clone()

template<typename T>

virtual boost::shared_ptr<Expression> gtsam::Expression< T >::clone ( ) const

inlinevirtual

Returns

a "deep" copy of this Expression "deep" is in quotes because the ExpressionNode hierarchy is not cloned. The intent is for derived classes to be copied using only a Base pointer.

value()

template<typename T >

T gtsam::Expression< T >::value	(	const Values &	values,
		boost::optional< std::vector< Matrix > & >	H = boost::none
	)		const

Return value and optional derivatives, reverse AD version Notes: this is not terribly efficient, and H should have correct size.

The order of the Jacobians is same as keys in either keys() or dims()

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

• /Users/dellaert/git/gtsam/gtsam/nonlinear/Expression.h
• /Users/dellaert/git/gtsam/gtsam/nonlinear/Expression-inl.h