Abstract base class for constraints of kinematic fits. More...
#include <ParticleConstraint.h>
Public Member Functions | |
| ParticleConstraint () | |
| Creates an empty ParticleConstraint object. | |
| virtual | ~ParticleConstraint () |
| Virtual destructor. | |
| virtual void | setFOList (std::vector< ParticleFitObject * > *fitobjects_) |
| Adds several ParticleFitObject objects to the list. More... | |
| virtual void | addToFOList (ParticleFitObject &fitobject, int flag=1) |
| Adds one ParticleFitObject objects to the list. | |
| virtual void | resetFOList () |
| Resests ParticleFitObject list. | |
| virtual void | invalidateCache () const |
| Invalidates any cached values for the next event. | |
 Public Member Functions inherited from BaseHardConstraint | |
| virtual | ~BaseHardConstraint () |
| Virtual destructor. | |
| virtual void | add1stDerivativesToMatrix (double *M, int idim) const |
| Adds first order derivatives to global covariance matrix M. More... | |
| virtual void | add2ndDerivativesToMatrix (double *M, int idim, double lambda) const |
| Adds second order derivatives to global covariance matrix M. More... | |
| virtual void | addToGlobalChi2DerVector (double *y, int idim, double lambda) const |
| Add lambda times derivatives of chi squared to global derivative vector. More... | |
| virtual double | dirDer (double *p, double *w, int idim, double mu=1) |
| Calculate directional derivative. More... | |
| virtual double | dirDerAbs (double *p, double *w, int idim, double mu=1) |
| Calculate directional derivative for abs(c) More... | |
| virtual bool | secondDerivatives (int i, int j, double *derivatives) const =0 |
| Second derivatives with respect to the meta-variables of Fit objects i and j; result false if all derivatives are zero. More... | |
| virtual bool | firstDerivatives (int i, double *derivatives) const =0 |
| First derivatives with respect to the meta-variables of Fit objects i; result false if all derivatives are zero. More... | |
| virtual int | getVarBasis () const =0 |
| virtual double | getValue () const =0 |
| Returns the value of the constraint. | |
| virtual double | getError () const |
| Returns the error on the value of the constraint. | |
| virtual void | getDerivatives (int idim, double der[]) const =0 |
| Get first order derivatives. More... | |
| virtual int | getGlobalNum () const |
| Accesses position of constraint in global constraint list. | |
| virtual void | setGlobalNum (int iglobal) |
| Sets position of constraint in global constraint list. More... | |
| virtual void | printFirstDerivatives () const |
| virtual void | printSecondDerivatives () const |
| virtual void | test1stDerivatives () |
| virtual void | test2ndDerivatives () |
| virtual double | num1stDerivative (int ifo, int ilocal, double eps) |
| Evaluates numerically the 1st derivative w.r.t. a parameter. More... | |
| virtual double | num2ndDerivative (int ifo1, int ilocal1, double eps1, int ifo2, int ilocal2, double eps2) |
| Evaluates numerically the 2nd derivative w.r.t. 2 parameters. More... | |
| Public Member Functions inherited from BaseConstraint | |
| BaseConstraint () | |
| Creates an empty BaseConstraint object. | |
| BaseConstraint (const BaseConstraint &rhs) | |
| Copy constructor. More... | |
| BaseConstraint & | operator= (const BaseConstraint &rhs) |
| Assignment. More... | |
| virtual | ~BaseConstraint () |
| Virtual destructor. | |
| virtual const char * | getName () const |
| Returns the name of the constraint. | |
| virtual void | setName (const char *name_) |
| Set object's name. | |
| virtual std::ostream & | print (std::ostream &os) const |
| print object to ostream More... | |
Additional Inherited Members | |
| Protected Types inherited from BaseHardConstraint | |
|
typedef std::vector < BaseFitObject * > | FitObjectContainer |
| Vector of pointers to ParticleFitObjects. | |
|
typedef FitObjectContainer::iterator | FitObjectIterator |
| Iterator through vector of pointers to ParticleFitObjects. | |
|
typedef FitObjectContainer::const_iterator | ConstFitObjectIterator |
| Constant iterator through vector of pointers to ParticleFitObjects. | |
| Protected Attributes inherited from BaseHardConstraint | |
| FitObjectContainer | fitobjects |
| The FitObjectContainer. | |
| std::vector< double > | derivatives |
| The derivatives. | |
| std::vector< int > | flags |
| The flags can be used to divide the FitObjectContainer into several subsets used for example to implement an equal mass constraint (see MassConstraint). More... | |
| int | globalNum |
| Position of constraint in global constraint list. | |
| Protected Attributes inherited from BaseConstraint | |
| char * | name |
| Related Functions inherited from BaseConstraint | |
| std::ostream & | operator<< (std::ostream &os, const BaseConstraint &bc) |
| Prints out a BaseConstraint, using its print method. More... | |
Detailed Description
Abstract base class for constraints of kinematic fits.
This class defines the minimal functionality any constraint class must provide. First of all a constraint should know on with particles (or FitObject) it is applied. Where as for example a constraint on the total transvese momentum takes into account all particles in the event, an invariant mass constraint usually applies only to a subset of particles.
The particle list is implemented as a vector containing pointers to objects derived from ParticleFitObject and can be either set a whole (setFOList) or enlarged by adding a single ParticleFitObject (addToFOList).
From the four–momenta of all concerned fit objects the constraint has to be able to calculate its current value (getValue). Constraints should be formulated such that a value of zero corresponds to a perfectly fulfilled constraint.
In order to find a solution to the constrained minimisation problem, fit algorithms usually need the first order derivatives of the constraint with respect to the fit parameters. Since many constraints can be most easily expressed in terms of E, px, py, pz, the constraints supply their derivatives w.r.t. these parameters. If a FitObject uses a different parametrisation, it is its own task to provide the additional derivatives of E, px, py, pz w.r.t. the parameters of the FitObject. Thus it is easily possible to use FitObjects with different kinds of parametrisations under the same constraint. Some fit algorithms also need the second derivatives of the constraint, i.e. the NewtonFitter.
First and second order derivatives of each constraint can be added directly to the global covariance matrix containing the derivatives of all constraints w.r.t. to all parameters (add1stDerivativesToMatrix, add2ndDerivativesToMatrix). This requires the constraint to know its position in the overall list of constraints (globalNum).
Author: Jenny List, Benno List
- Date:
- 2008/02/12 16:43:26
- Author:
- blist
Member Function Documentation
|
inlinevirtual |
Adds several ParticleFitObject objects to the list.
- Parameters
-
fitobjects_ A list of BaseFitObject objects
References BaseHardConstraint::fitobjects, and BaseHardConstraint::flags.
The documentation for this class was generated from the following file:
