gtsam
4.0.0
gtsam
|
Binary factor to estimate parameters of zero-mean Gaussian white noise.
This factor uses the mean-precision parameterization.
Takes three template arguments: Key: key type to use for mean Key: key type to use for precision Values: Values type for optimization
Standard Constructors | |
WhiteNoiseFactor (double z, Key meanKey, Key precisionKey) | |
Construct from measurement. More... | |
Advanced Constructors | |
virtual | ~WhiteNoiseFactor () |
Destructor. | |
Testable | |
void | print (const std::string &p="WhiteNoiseFactor", const KeyFormatter &keyFormatter=DefaultKeyFormatter) const |
Print. | |
Standard Interface | |
virtual size_t | dim () const |
get the dimension of the factor (number of rows on linearization) | |
double | error (const Values &x) const |
Calculate the error of the factor, typically equal to log-likelihood. | |
virtual Vector | unwhitenedError (const Values &x) const |
Vector of errors "unwhitened" does not make sense for this factor What is meant typically is only "e" above Here we shoehorn sqrt(2*error(p)) TODO: Where is this used? should disappear. | |
Advanced Interface | |
virtual boost::shared_ptr< GaussianFactor > | linearize (const Values &x) const |
linearize returns a Hessianfactor that is an approximation of error(p) | |
Static Public Member Functions | |
static double | f (double z, double u, double p) |
negative log likelihood as a function of mean \( \mu \) and precision \( \tau \) \[ f(z, \tau, \mu) = -\log \left( \frac{\sqrt{\tau}}{\sqrt{2\pi}} \exp(-0.5\tau(z-\mu)^2) \right) = \log(\sqrt{2\pi}) - 0.5* \log(\tau) + 0.5\tau(z-\mu)^2 \] | |
static HessianFactor::shared_ptr | linearize (double z, double u, double p, Key j1, Key j2) |
linearize returns a Hessianfactor that approximates error Hessian is \[ 0.5f - x^T g + 0.5*x^T G x \] Taylor expansion is \[ f(x+dx) = f(x) + df(x) dx + 0.5 ddf(x) dx^2 \] So f = 2 f(x), g = -df(x), G = ddf(x) | |
Additional Inherited Members | |
Public Member Functions inherited from gtsam::NonlinearFactor | |
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. | |
virtual bool | equals (const NonlinearFactor &f, double tol=1e-9) const |
Check if two factors are equal. | |
virtual | ~NonlinearFactor () |
Destructor. | |
virtual bool | active (const Values &) const |
Checks whether a factor should be used based on a set of values. More... | |
virtual shared_ptr | clone () const |
Creates a shared_ptr clone of the factor - needs to be specialized to allow for subclasses. More... | |
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. | |
shared_ptr | rekey (const KeyVector &new_keys) const |
Clones a factor and fully replaces its keys. More... | |
Public Member Functions inherited from gtsam::Factor | |
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 |
void | print (const std::string &s="Factor", const KeyFormatter &formatter=DefaultKeyFormatter) const |
print | |
void | printKeys (const std::string &s="Factor", const KeyFormatter &formatter=DefaultKeyFormatter) const |
print only keys | |
KeyVector & | keys () |
iterator | begin () |
Iterator at beginning of involved variable keys. | |
iterator | end () |
Iterator at end of involved variable keys. | |
Public Types inherited from gtsam::NonlinearFactor | |
typedef boost::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::NonlinearFactor | |
typedef Factor | Base |
typedef NonlinearFactor | This |
Protected Member Functions inherited from gtsam::Factor | |
Factor () | |
Default constructor for I/O. | |
template<typename CONTAINER > | |
Factor (const CONTAINER &keys) | |
Construct factor from container of keys. More... | |
template<typename ITERATOR > | |
Factor (ITERATOR first, ITERATOR last) | |
Construct factor from iterator keys. More... | |
bool | equals (const This &other, double tol=1e-9) const |
check equality | |
Static Protected Member Functions inherited from gtsam::Factor | |
template<typename CONTAINER > | |
static Factor | FromKeys (const CONTAINER &keys) |
Construct factor from container of keys. More... | |
template<typename ITERATOR > | |
static Factor | FromIterators (ITERATOR first, ITERATOR last) |
Construct factor from iterator keys. More... | |
Protected Attributes inherited from gtsam::Factor | |
KeyVector | keys_ |
The keys involved in this factor. | |
Construct from measurement.
z | Measurment value |
meanKey | Key for mean variable |
precisionKey | Key for precision variable |