hitfit::Fourvec_Constraint_Calculator Class Reference

Concrete realization of the Constraint_Calculator class. Evaluate constraints at the point described by x and y (well-measured and poorly-measured variables, respectively). The results should be stored in F. Bx and By should be set to the gradients of F with respect to x and y, respectively. More...

Inheritance diagram for hitfit::Fourvec_Constraint_Calculator:

Public Member Functions
bool	calculate_constraints (Row_Vector &F, Matrix &Bx, Matrix &By) const
	Calculate the constraint functions and gradients. More...
virtual bool	eval (const Column_Vector &x, const Column_Vector &y, Row_Vector &F, Matrix &Bx, Matrix &By) override
	Evaluate constraints at the point described by x and y (well-measured and poorly-measured variables, respectively). The results should be stored in F. Bx and By should be set to the gradients of F with respect to x and y, respectively. More...
	Fourvec_Constraint_Calculator (Fourvec_Event &ev, const vector< Constraint > &constraints, const Fourvec_Constrainer_Args &args)
	Constructor. More...
virtual	~Fourvec_Constraint_Calculator ()
Public Member Functions inherited from hitfit::Constraint_Calculator
	Constraint_Calculator (int nconstraints)
int	nconstraints () const
virtual	~Constraint_Calculator ()

Private Attributes
const Fourvec_Constrainer_Args &	_args
const vector< Constraint > &	_constraints
Fourvec_Event &	_ev
Pair_Table	_pt

Detailed Description

Concrete realization of the Constraint_Calculator class. Evaluate constraints at the point described by x and y (well-measured and poorly-measured variables, respectively). The results should be stored in F. Bx and By should be set to the gradients of F with respect to x and y, respectively.

Parameters

x	Column_Vector of well-measured variables.
y	Column_Vector of poorly-measured variables.
F	Row_Vector contains the results of the constraint evaluation.
Bx	Gradients of F with respect to x
By	Gradients of F with respect to y

Return:

true if the point (x,y) is accepted.
false if the point (x,y) is rejected (i.e., in an unphysical region). The constraints need not be evaluated in that case.

Definition at line 1375 of file Fourvec_Constrainer.cc.

Constructor & Destructor Documentation

hitfit::Fourvec_Constraint_Calculator::Fourvec_Constraint_Calculator	(	Fourvec_Event &	ev,
		const vector< Constraint > &	constraints,
		const Fourvec_Constrainer_Args &	args
	)

Constructor.

Parameters

ev	The event we are fitting.
constraints	The list of constraints.
args	The parameter settings for this instance.

Definition at line 1433 of file Fourvec_Constrainer.cc.

  : Constraint_Calculator (constraints.size() +
                           ((ev.has_neutrino() || args.ignore_met()) ? 0 : 2)),
    _ev (ev),
    _constraints (constraints),
    _args (args),
    _pt (constraints, ev)

{
}

virtual hitfit::Fourvec_Constraint_Calculator::~Fourvec_Constraint_Calculator ( )

inlinevirtual

Definition at line 1386 of file Fourvec_Constrainer.cc.

{}

Member Function Documentation

bool hitfit::Fourvec_Constraint_Calculator::calculate_constraints	(	Row_Vector &	F,
		Matrix &	Bx,
		Matrix &	By
	)		const

Calculate the constraint functions and gradients.

Parameters

F	Vector of constraint values.
Bx	The gradient of well-measured variables.
By	The gradient of poorly-measured variables.

Output:

• F.
• Bx.
• By.

Definition at line 1471 of file Fourvec_Constrainer.cc.

References hitfit::eta_offs, F(), relval_steps::k, hitfit::FE_Obj::muon_p, hitfit::FE_Obj::p, and hitfit::p_offs.

Referenced by eval().

{
  // Clear the matrices.
  Bx = Matrix (Bx.num_row(), Bx.num_col(), 0);
  By = Matrix (By.num_row(), By.num_col(), 0);
  F = Row_Vector (F.num_col(), 0);

  const double p_eps = 1e-10;

  if (_ev.has_neutrino() && _ev.nu().z() > _args.e_com()) {
    return false;
  }

  int nobjs = _ev.nobjs ();

  // Reject the point if any of the momenta get too small.
  for (int j=0; j<nobjs; j++) {
    if (_ev.obj(j).p.perp() <= p_eps || _ev.obj(j).p.e() <= p_eps) {
      return false;
    }
  }

  if (! calculate_mass_constraints (_ev, _pt, _constraints, _args.use_e(),
                                    F, Bx, By))
    return false;

  if (_ev.has_neutrino())
    convert_neutrino (_ev, _args.use_e(), Bx, By);
  else if (!_args.ignore_met())
  {
    /* kt constraints */
    calculate_kt_constraints (_ev, _args.use_e(), F, Bx);
  }

  /* convert d/dtheta to d/deta */
  for (int j=0; j<nobjs; j++) {
    ddtheta_to_ddeta (obj_index (j) + eta_offs,
                      _ev.obj(j).p.cosTheta(),
                      Bx);
  }

  /* handle muons */
  for (int j=0; j<nobjs; j++) {
    const FE_Obj& obj = _ev.obj (j);
    if (obj.muon_p) {
      // Again, E vs. P doesn't matter here since we assume muons to be massless.
      double pmu2 = obj.p.vect().mag2();
      int ndx = obj_index (j) + p_offs;
      for (int k=1; k<=Bx.num_col(); k++)
    Bx(ndx, k) = - Bx(ndx, k) * pmu2;
    }
  }

  return true;
}

bool hitfit::Fourvec_Constraint_Calculator::eval ( const Column_Vector &  x, const Column_Vector &  y, Row_Vector &  F, Matrix &  Bx, Matrix &  By  )

overridevirtual

Evaluate constraints at the point described by x and y (well-measured and poorly-measured variables, respectively). The results should be stored in F. Bx and By should be set to the gradients of F with respect to x and y, respectively.

Parameters

x	Column_Vector of well-measured variables.
y	Column_Vector of poorly-measured variables.
F	Row_Vector contains the results of the constraint evaluation.
Bx	Gradients of F with respect to x
By	Gradients of F with respect to y

Output:

• F.
• Bx.
• By.

Return:

true if the point (x,y) is accepted.
false if the point (x,y) is rejected (i.e., in an unphysical region). The constraints need not be evaluated in that case.

Implements hitfit::Constraint_Calculator.

Definition at line 1567 of file Fourvec_Constrainer.cc.

References _args, _ev, calculate_constraints(), hitfit::eta_offs, hitfit::Fourvec_Event::has_neutrino(), hitfit::Fourvec_Constrainer_Args::ignore_met(), hitfit::Fourvec_Event::nobjs(), hitfit::p_offs, and hitfit::Fourvec_Constrainer_Args::use_e().

{
  int nobjs = _ev.nobjs();

  const double p_eps = 1e-10;
  const double eta_max = 10;

  // Give up if we've gone into an obviously unphysical region.
  for (int j=0; j<nobjs; j++)
    if (x(obj_index (j) + p_offs) < p_eps ||
        fabs(x(obj_index (j) + eta_offs)) > eta_max) {
      return false;
    }

  unpack_event (_ev, x, y, _args.use_e(),
                _ev.has_neutrino() || !_args.ignore_met());

  return calculate_constraints (F, Bx, By);
}

Member Data Documentation

const Fourvec_Constrainer_Args& hitfit::Fourvec_Constraint_Calculator::_args

private

Definition at line 1416 of file Fourvec_Constrainer.cc.

Referenced by Vispa.Main.Application.Application::_readCommandLineAttributes(), and eval().

const vector<Constraint>& hitfit::Fourvec_Constraint_Calculator::_constraints

private

Definition at line 1413 of file Fourvec_Constrainer.cc.

Fourvec_Event& hitfit::Fourvec_Constraint_Calculator::_ev

private

Definition at line 1410 of file Fourvec_Constrainer.cc.

Referenced by eval().

Pair_Table hitfit::Fourvec_Constraint_Calculator::_pt

private

Definition at line 1419 of file Fourvec_Constrainer.cc.