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StEEmcPointUtils Class Reference
Inheritance diagram for StEEmcPointUtils:
StEEmcPointMaker StEEmcPointFitMaker StEEmcPointTreeMaker

Public Member Functions

Bool_t opening_angle_cut (StEEmcPoint &p1, StEEmcPoint &p2, Float_t energy, Float_t mass=0.135, Float_t frac=0.3)
StEEmcPointVec_t find_best_points (StEEmcPointVec_t points, Float_t em_energy, Bool_t &stat, Float_t &chi2, Int_t npoint=1)
Bool_t no_parallel_smd_clusters (StEEmcPointVec_t points, Int_t npoint)

Detailed Description

Definition at line 9 of file StEEmcPointUtils.h.

Member Function Documentation

StEEmcPointVec_t StEEmcPointUtils::find_best_points ( StEEmcPointVec_t  points,
Float_t  em_energy,
Bool_t &  stat,
Float_t &  chi2,
Int_t  npoint = 1 

Given a vector of points matching some energy in the endcap, return the best set of points using the following criteria:

1) assume an SMD sampling fraction of 0.6% 2) predict energy deposit in SMD 3) compute a "chi^2" = ( epredict - epoint )^2 + 4.0 ( esmdu - esmdv )^2

The set of npoints which minimizes this "chi^2" will be returned

NOTE– points which lie along the same strips will not be considered. it will be possible that no set of points will find an optimal minimum. If so, stat returns false.

pointsInput vector of points
em_energyElectormagnetic energy we're fitting to
statfalse if it fails to find a good set of points
chi2the "chi2" of the minimization
npointsthe number of points we're looking for.

Check sanity. Number of requested points must be no bigger than our vector.

Loop over all permutations. Calculate chi2 for the firsn npoint points.

require all smd clusters in permutation to be on different smd strips

Definition at line 18 of file StEEmcPointUtils.cxx.

References no_parallel_smd_clusters().

Bool_t StEEmcPointUtils::no_parallel_smd_clusters ( StEEmcPointVec_t  points,
Int_t  npoint 

Test if the first npoint points in the vector have SMD strips which are along the same strips (means are equal)

no clusters found along parallel strips

Definition at line 61 of file StEEmcPointUtils.cxx.

Referenced by find_best_points().

Bool_t StEEmcPointUtils::opening_angle_cut ( StEEmcPoint p1,
StEEmcPoint p2,
Float_t  energy,
Float_t  mass = 0.135,
Float_t  frac = 0.3 

Returns true if the two points are outside a given fraction of the minimum opening angle for a meson with a given mass. Default is set for 30% of the pi0 minimum opening angle at a given energy.

p1point 1
p2point 2
energyenergy of candidate
massmass of meson
fracfraction of opening angle to test (default=0.3).

Definition at line 10 of file StEEmcPointUtils.cxx.

References StEEmcPoint::position().

The documentation for this class was generated from the following files: