Node

A Node is an internal class invented to hold an experimental reconstructed object (represented by the class RecObject), a State and the quantities that relate both objects (residual). This class is essential for local fits (i.e. Kalman Filter), which require a local definition of the state vector. The data members are:

// the model to which the node has been fitted
std::string name;
// a map of additional names
std::map< std::string, std::string > names;

// status of the node: fitted or not (state filled or not), etc
std::map< std::string, bool > status;
// the number of degrees of freedom
int ndof;
// quality of the local fit:chi2
double quality;
// map of qualities of the local fit (”chi2”, “chi2ndf”, etc)
std::map< std::string, double > qualities;

// The local state
State* state;
// The reconstructed object associated to this node
RecObject* recObject;

// the residual and its covariance matrix
HyperVector residual;
// residuals map. Some fitters produce several residuals (i.e. Kalman Filter)
std::map< std::string, HyperVector > residual_map;

The name and the map of names are inherited from the base class NamedObject, while the status, NDOF, quality, map of qualities are inherited from the base class RecResult.