gtsam::ImuFactor2WithGravityT< PIM, GRAVITY > Class Template Reference

Detailed Description

template<class PIM = PreintegratedImuMeasurements, class GRAVITY = Unit3>
class gtsam::ImuFactor2WithGravityT< PIM, GRAVITY >

ImuFactor2WithGravityT is the NavState version of ImuFactorWithGravityT, just as ImuFactor2T is the NavState version of ImuFactorT: a 4-ways factor involving the previous and current NavStates, the bias estimate, and a GRAVITY variable so that gravity can be optimized instead of being fixed by the preintegration parameters.

Two parametrizations are provided, see ImuFactor2WithGravityDirection and ImuFactor2WithGravityVector.

The observability caveat of ImuFactorWithGravityT applies here as well: gravity in the nav frame is entangled with the initial attitude, so a graph should anchor one of the two.

Inheritance diagram for gtsam::ImuFactor2WithGravityT< PIM, GRAVITY >:

Public Member Functions
	ImuFactor2WithGravityT ()
	Default constructor - only use for serialization.
	ImuFactor2WithGravityT (Key state_i, Key state_j, Key bias, Key gravity, const PIM &preintegratedMeasurements, std::optional< double > gravityMagnitude={})
	Constructor.
gtsam::NonlinearFactor::shared_ptr	clone () const override
const PIM &	preintegratedMeasurements () const
	Access the preintegrated measurements.
double	gravityMagnitude () const
	The gravity magnitude used by the Unit3 parametrization.
Vector9	evaluateError (const NavState &state_i, const NavState &state_j, const imuBias::ConstantBias &bias_i, const GRAVITY &gravity, OptionalMatrixType H1, OptionalMatrixType H2, OptionalMatrixType H3, OptionalMatrixType H4) const override
	implement functions needed to derive from Factor
virtual Vector9	evaluateError (const ValueTypes &... x, OptionalMatrixTypeT< ValueTypes >... H) const =0
	Override evaluateError to finish implementing an n-way factor.
Vector	evaluateError (const ValueTypes &... x, MatrixTypeT< ValueTypes > &... H) const
	If all the optional arguments are matrices then redirect the call to the one which takes pointers.
Vector	evaluateError (const ValueTypes &... x) const
	No-Jacobians requested function overload.
AreAllMatrixRefs< Vector, OptionalJacArgs... >	evaluateError (const ValueTypes &... x, OptionalJacArgs &&... H) const
	Some (but not all) optional Jacobians are omitted (function overload) and the jacobians are l-value references to matrices.
Testable
void	print (const std::string &s="", const KeyFormatter &keyFormatter=DefaultKeyFormatter) const override
	print
bool	equals (const NonlinearFactor &expected, double tol=1e-9) const override
	Check if two factors are equal.
Public Member Functions inherited from gtsam::NoiseModelFactorT< Vector9, NavState, NavState, imuBias::ConstantBias, Unit3 >
Vector	unwhitenedError (const Values &x, std::vector< Matrix > &H) const
	support taking in the actual vector instead of the pointer as well to get access to this version of the function from derived classes one will need to use the "using" keyword and specify that like this: public: using NoiseModelFactor::unwhitenedError;
Key	key () const
	Returns a key.
	NoiseModelFactorT ()
	Default Constructor for I/O.
Key	key1 () const
Key	key2 () const
Key	key3 () const
Key	key4 () const
Key	key5 () const
Key	key6 () const
std::shared_ptr< GaussianFactor >	linearize (const Values &values) const override
	Linearize factors whose error and argument dimensions are all fixed to an arbitrary-arity FixedJacobianFactor.
Public Member Functions inherited from gtsam::NoiseModelFactor
	NoiseModelFactor ()
	Default constructor for I/O only.
	~NoiseModelFactor () override
	Destructor.
template<typename CONTAINER>
	NoiseModelFactor (const SharedNoiseModel &noiseModel, const CONTAINER &keys)
	Constructor.
void	print (const std::string &s="", const KeyFormatter &keyFormatter=DefaultKeyFormatter) const override
	Print.
bool	equals (const NonlinearFactor &f, double tol=1e-9) const override
	Check if two factors are equal.
size_t	dim () const override
	get the dimension of the factor (number of rows on linearization)
const SharedNoiseModel &	noiseModel () const
	access to the noise model
virtual Vector	unwhitenedError (const Values &x, OptionalMatrixVecType H=nullptr) const =0
	Error function without the NoiseModel, \( z-h(x) \).
Vector	unwhitenedError (const Values &x, std::vector< Matrix > &H) const
	support taking in the actual vector instead of the pointer as well to get access to this version of the function from derived classes one will need to use the "using" keyword and specify that like this: public: using NoiseModelFactor::unwhitenedError;
Vector	whitenedError (const Values &c) const
	Vector of errors, whitened This is the raw error, i.e., i.e.
Vector	unweightedWhitenedError (const Values &c) const
	Vector of errors, whitened, but unweighted by any loss function.
double	weight (const Values &c) const
	Compute the effective weight of the factor from the noise model.
double	error (const Values &c) const override
	Calculate the error of the factor.
shared_ptr	cloneWithNewNoiseModel (const SharedNoiseModel newNoise) const
	Creates a shared_ptr clone of the factor with a new noise model.
double	error (const HybridValues &c) const override
	All factor types need to implement an error function.
	NonlinearFactor ()
	Default constructor for I/O only.
template<typename CONTAINER>
	NonlinearFactor (const CONTAINER &keys)
	Constructor from a collection of the keys involved in this factor.
void	print (const std::string &s="", const KeyFormatter &keyFormatter=DefaultKeyFormatter) const override
	print
double	error (const HybridValues &c) const override
	All factor types need to implement an error function.
virtual bool	active (const Values &c) const
	Checks whether a factor should be used based on a set of values.
virtual void	qcqpFactors (NonlinearFactorGraph *costs, NonlinearEqualityConstraints *constraints, size_t columnDimension=1) const
	Add this factor's QCQP cost and constraints over matrix-valued QCQP variables with the given column dimension.
virtual shared_ptr	rekey (const std::map< Key, Key > &rekey_mapping) const
	Creates a shared_ptr clone of the factor with different keys using a map from old->new keys.
virtual shared_ptr	rekey (const KeyVector &new_keys) const
	Clones a factor and fully replaces its keys.
virtual bool	sendable () const
	Should the factor be evaluated in the same thread as the caller This is to enable factors that has shared states (like the Python GIL lock).
Public Member Functions inherited from gtsam::Factor
virtual	~Factor ()=default
	Default destructor.
bool	empty () const
	Whether the factor is empty (involves zero variables).
Key	front () const
	First key.
Key	back () const
	Last key.
const_iterator	find (Key key) const
	find
const KeyVector &	keys () const
	Access the factor's involved variable keys.
const_iterator	begin () const
	Iterator at beginning of involved variable keys.
const_iterator	end () const
	Iterator at end of involved variable keys.
size_t	size () const
virtual void	printKeys (const std::string &s="Factor", const KeyFormatter &formatter=DefaultKeyFormatter) const
	print only keys
bool	equals (const This &other, double tol=1e-9) const
	check equality
KeyVector &	keys ()
iterator	begin ()
	Iterator at beginning of involved variable keys.
iterator	end ()
	Iterator at end of involved variable keys.

Additional Inherited Members
Static Public Attributes inherited from gtsam::NoiseModelFactorT< Vector9, NavState, NavState, imuBias::ConstantBias, Unit3 >
static constexpr auto	N
	N is the number of variables (N-way factor).
Public Types inherited from gtsam::NoiseModelFactorT< Vector9, NavState, NavState, imuBias::ConstantBias, Unit3 >
using	ValueType
	The type of the I'th template param can be obtained as ValueType.
Public Types inherited from gtsam::NoiseModelFactor
typedef std::shared_ptr< This >	shared_ptr
	Noise model.
Public Types inherited from gtsam::NonlinearFactor
typedef std::shared_ptr< This >	shared_ptr
Public Types inherited from gtsam::Factor
typedef KeyVector::iterator	iterator
	Iterator over keys.
typedef KeyVector::const_iterator	const_iterator
	Const iterator over keys.
Protected Types inherited from gtsam::NoiseModelFactorT< Vector9, NavState, NavState, imuBias::ConstantBias, Unit3 >
using	Base
using	This
using	OptionalMatrixTypeT
using	KeyType
using	MatrixTypeT
using	IsConvertible
using	IndexIsValid
using	ContainerElementType
using	IsContainerOfKeys
using	AreAllMatrixRefs
	A helper alias to check if a list of args are all references to a matrix or not.
using	IsMatrixPointer
using	IsNullpointer
using	AreAllMatrixPtrs
	A helper alias to check if a list of args are all pointers to a matrix or not.
Protected Types inherited from gtsam::NoiseModelFactor
typedef NonlinearFactor	Base
typedef NoiseModelFactor	This
Protected Types inherited from gtsam::NonlinearFactor
typedef Factor	Base
typedef NonlinearFactor	This
Protected Member Functions inherited from gtsam::NoiseModelFactor
	NoiseModelFactor (const SharedNoiseModel &noiseModel)
	Constructor - only for subclasses, as this does not set keys.
	Factor ()
	Default constructor for I/O.
template<typename CONTAINER>
	Factor (const CONTAINER &keys)
	Construct factor from container of keys.
template<typename ITERATOR>
	Factor (ITERATOR first, ITERATOR last)
	Construct factor from iterator keys.
template<typename CONTAINER>
static Factor	FromKeys (const CONTAINER &keys)
	Construct factor from container of keys.
template<typename ITERATOR>
static Factor	FromIterators (ITERATOR first, ITERATOR last)
	Construct factor from iterator keys.
Protected Attributes inherited from gtsam::NoiseModelFactor
SharedNoiseModel	noiseModel_
Protected Attributes inherited from gtsam::Factor
KeyVector	keys_
	The keys involved in this factor.

Constructor & Destructor Documentation

ImuFactor2WithGravityT()

template<class PIM = PreintegratedImuMeasurements, class GRAVITY = Unit3>

gtsam::ImuFactor2WithGravityT< PIM, GRAVITY >::ImuFactor2WithGravityT ( Key state_i, Key state_j, Key bias, Key gravity, const PIM & preintegratedMeasurements, std::optional< double > gravityMagnitude = {} )

inline

Constructor.

Parameters

state_i	Previous state key
state_j	Current state key
bias	Previous bias key
gravity	Gravity key
preintegratedMeasurements	The preintegrated measurements since the last state
gravityMagnitude	The known gravity magnitude for the Unit3 parametrization; defaults to the norm of the gravity vector in the preintegration params. Must not be provided for the Point3 parametrization, where the magnitude is part of the optimized variable; to constrain it, add a VectorNormFactor<3> on the gravity variable.

Member Function Documentation

clone()

template<class PIM = PreintegratedImuMeasurements, class GRAVITY = Unit3>

gtsam::NonlinearFactor::shared_ptr gtsam::ImuFactor2WithGravityT< PIM, GRAVITY >::clone ( ) const

inlineoverridevirtual

Returns

a deep copy of this factor

Reimplemented from gtsam::NonlinearFactor.

equals()

template<class PIM, class GRAVITY>

bool gtsam::ImuFactor2WithGravityT< PIM, GRAVITY >::equals ( const NonlinearFactor & f, double tol = 1e-9 ) const

overridevirtual

Check if two factors are equal.

Reimplemented from gtsam::NonlinearFactor.

evaluateError() [1/5]

template<class PIM, class GRAVITY>

Vector9 gtsam::ImuFactor2WithGravityT< PIM, GRAVITY >::evaluateError ( const NavState & state_i, const NavState & state_j, const imuBias::ConstantBias & bias_i, const GRAVITY & gravity, OptionalMatrixType H1, OptionalMatrixType H2, OptionalMatrixType H3, OptionalMatrixType H4 ) const

override

implement functions needed to derive from Factor

vector of errors

evaluateError() [2/5]

template<class PIM = PreintegratedImuMeasurements, class GRAVITY = Unit3>

Vector gtsam::NoiseModelFactorT< Vector9, ValueTypes >::evaluateError ( const ValueTypes &... x ) const

inline

No-Jacobians requested function overload.

This specializes the version below to avoid recursive calls since this is commonly used.

e.g. const Vector error = factor.evaluateError(pose, point);

evaluateError() [3/5]

template<class PIM = PreintegratedImuMeasurements, class GRAVITY = Unit3>

Vector gtsam::NoiseModelFactorT< Vector9, ValueTypes >::evaluateError ( const ValueTypes &... x, MatrixTypeT< ValueTypes > &... H ) const

inline

If all the optional arguments are matrices then redirect the call to the one which takes pointers.

To get access to this version of the function from derived classes one will need to use the "using" keyword and specify that like this: public: using NoiseModelFactorT<list the value types here>::evaluateError;

evaluateError() [4/5]

template<class PIM = PreintegratedImuMeasurements, class GRAVITY = Unit3>

AreAllMatrixRefs< Vector, OptionalJacArgs... > gtsam::NoiseModelFactorT< Vector9, ValueTypes >::evaluateError ( const ValueTypes &... x, OptionalJacArgs &&... H ) const

inline

Some (but not all) optional Jacobians are omitted (function overload) and the jacobians are l-value references to matrices.

e.g. const Vector error = factor.evaluateError(pose, point, Hpose);

evaluateError() [5/5]

template<class PIM = PreintegratedImuMeasurements, class GRAVITY = Unit3>

virtual Vector9 gtsam::NoiseModelFactorT< Vector9, ValueTypes >::evaluateError ( const ValueTypes &... x, OptionalMatrixTypeT< ValueTypes >... H ) const

virtual

Override evaluateError to finish implementing an n-way factor.

Both the x and H arguments are written here as parameter packs, but when overriding this method, you probably want to explicitly write them out. For example, for a 2-way factor with variable types Pose3 and Point3, you should implement:

Vector evaluateError(
    const Pose3& x1, const Point3& x2,
    OptionalMatrixType H1 = OptionalNone,
    OptionalMatrixType H2 = OptionalNone) const override { ... }

If any of the optional Matrix reference arguments are specified, it should compute both the function evaluation and its derivative(s) in the requested variables.

Parameters

	x	The values of the variables to evaluate the error for. Passed in as separate arguments.
[out]	H	The Jacobian with respect to each variable (optional).

Implements gtsam::NoiseModelFactorT< Vector9, NavState, NavState, imuBias::ConstantBias, Unit3 >.

print()

template<class PIM, class GRAVITY>

void gtsam::ImuFactor2WithGravityT< PIM, GRAVITY >::print ( const std::string & s = "", const KeyFormatter & formatter = DefaultKeyFormatter ) const

overridevirtual

print

Reimplemented from gtsam::Factor.

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

• /tmp/gtsam-4.3.0-doxygen.rsXPUS/source/gtsam/navigation/ImuFactorWithGravity.h
• /tmp/gtsam-4.3.0-doxygen.rsXPUS/source/gtsam/navigation/ImuFactorWithGravity.cpp