gtsam/cpp/PriorFactor.h

67 lines
1.8 KiB
C++

/**
* @file PriorFactor.h
* @authors Frank Dellaert
**/
#pragma once
#include <ostream>
#include "NonlinearFactor.h"
#include "Pose2.h"
namespace gtsam {
/**
* A class for a soft prior on any Lie type
* T is the Lie group type, Config where the T's are gotten from
*/
template<class Config, class Key, class T>
class PriorFactor: public NonlinearFactor1<Config, Key, T> {
private:
typedef NonlinearFactor1<Config, Key, T> Base;
T prior_; /** The measurement */
Matrix square_root_inverse_covariance_; /** sqrt(inv(covariance)) */
public:
// shorthand for a smart pointer to a factor
typedef typename boost::shared_ptr<PriorFactor> shared_ptr;
/** Constructor */
PriorFactor(const Key& key, const T& prior, const Matrix& covariance) :
Base(1.0, key), prior_(prior) {
square_root_inverse_covariance_ = inverse_square_root(covariance);
}
/** implement functions needed for Testable */
/** print */
void print(const std::string& s) const {
Base::print(s);
prior_.print("prior");
gtsam::print(square_root_inverse_covariance_,
"Square Root Inverse Covariance");
}
/** equals */
bool equals(const NonlinearFactor<Config>& expected, double tol) const {
const PriorFactor<Config, Key, T> *e = dynamic_cast<const PriorFactor<
Config, Key, T>*> (&expected);
return e != NULL && Base::equals(expected) && this->prior_.equals(
e->prior_, tol);
}
/** implement functions needed to derive from Factor */
/** vector of errors */
Vector evaluateError(const T& p, boost::optional<Matrix&> H = boost::none) const {
if (H) (*H) = square_root_inverse_covariance_;
// manifold equivalent of h(x)-z -> log(z,h(x))
return square_root_inverse_covariance_ * logmap(prior_, p);
}
};
} /// namespace gtsam