The purpose is to add a call in THcHallCSpectrometer:TrackCalc
to fill variables in THcDC for the golden track.

THcHallCSpectrometer.h
----------------------
1) Add object THcDC* fDC
2) Eliminate object fShower since it was not being used.

THcHallCSpectrometer.cxx
----------------------
1) in ReadDatabase method cast fDC in detector "dc" is defined
2) in FindVertices method add call
    to fDC->SetFocalPlaneBestTrack(hit_gold_track)
    where hit_gold_track is the HaTracks array index
    of the golden track

THcDC.h
-------
1) Add method SetFocalPlaneBestTrack

THcDC.cxx
---------
1) Eliminate filling of best focal plane quantities
   in CoarseTrack which defined "best" by lowest chi2
2) Create method SetFocalPlaneBestTrack
   a)fills the best focal plane quantities using the golden track
   b) fills fResiduals using golden track

The change was made so that NonTrackingDetector could have information
on the "best" track in their FineProcess method.

In THcHallCSpectrometer::FindVertices the "best" track will be selected
and the Track object will its SetIndex method to set the index to 0 for
the best track. The other track will have index=1 or greater.

In the NonTrackingDetector FineProcess, the track that is selected to
be the "best" can be found by looping through the tracks checking
track index using Track.GetIndex() for find the track with Index=0.

In  the NonTrackingDetector's CoarseProcess they need to set quantities
for the Track object needed for selection of "best" track for the
"prune" and "usingscin" track selection methods.

1) In THcHallCSpectrometer:
  a) Moved selection methods of "best" track from TrackCalc to FindVertices.
  b) Removed setting of Golden Track in the selection methods.
  c) Add setting of Track Index=0 for "best" track in each selection method.
  d) Modified TrackCalc method to loop through Track object and find
     the track with Index=0 and set the Golden Track equal to this Track.

2) In THcHodoscope.cxx
  a) Moved all calculations in FineProcess into CoarseProcess
  b) CoarseProcess calculates the scintillator Beta for each Track
     and does Track->SetBeta.
  c) In determination "zcor" for corrected hits times
      use fBetaNominal instead fBetap from track. Still use Track
      to get distance.
  c) Eliminate fBetap variable which was using the Track momentum
  d) Add variable fBeta which is just from scintillator times.
  e) In FineProcess fill fBeta with the the beta associated
     with the "best" track determined by selecting Track with index=0

  Enforce variable conventions
  Default using_scin and using_prune selection to off
  Break different track selection methods into different class methods

section of THcHallCSpectrometer to be clearer.
Does not follow the fortran in detail, but should be doing the same
thing.

  There is some unclear code in the track selection that could
  do with improvement.

  Don't start variables that are not member variables with f
  Declare temporary variables as locally as possible
  Remove some unused member variables from THcHodoscope.h

    THcHallCSpectrometer inherits from THaSpectrometer which has method
    GetPcentral and a member fPcentral.
     THcHallCSpectrometer had been using fPCentral but decided to
    use fPcentral.
    Delete fPCentral in THcHallCSpectrometer.h
    Replace all fPCentral  by fPcentral in ReadDatabase and FindVertices methods.

  For the most part this is making sure that the loop variable in
  a for loop is of the same type as the variable that it is compared
  against (Often a UInt_t).

This reverts commit e9ce1040.

Conflicts:
	src/THcHallCSpectrometer.cxx

  For the most part this is making sure that the loop variable in
  a for loop is of the same type as the variable that it is compared
  against (Often a UInt_t).

Add THaSpectrometer::DefineVariables( mode );
to define those tree variables

  Convert some arrays that were fixed length to vectors.
  Since these arrays are only used local to the method
  ThcHallCSpectrometer::TrackCalc(), they were moved out of the class
  into the method.
  The affected arrays are fX2D, fY2D, f2XHits and f2YHits

      Selection of golden track using prune method is added.
      A bug is also fixed in THcHodoscope class
      Number of pmts hits, focal plane time, good time for plane 4
      and good time for plane 3 are set to the tracks in
      THcHodoscope class.

  This insures that 5th exponent is zero if not specified on recon file

- no need to call Nint() on an integer

    Hardwired numbers are fixed in THcHallcSpectrometer class.
    Generalized functions for center of hodoscope planes and
    their spacings are defined.

Goldent track is moved to THcHallCSpectrometer::TrackCalc()
  if  fSelUsingScin == 0 then golden track is calculated just
  like podd. i.e. it is the first track with minimum chi2/ndf
  with sorting ON

  if fSelUsingScin == 1 then golden track is calculetd just like
  engine/HTRACKING/h_select_best_track_using_scin.h. This method
  gives the best track with minimum value of chi2/ndf but with
  additional cuts on the tracks. These cuts are on dedx, beta
  and on energy.

  This commit also corrects and modifies the beta code written
  in the THcHodoscope::FineProcess

  At this point we have godlend track and in additoion to
  previous vlues the following values are set to a track:
  Energy, beta, chi2 of beta and dedx[track][first hit].

NOTE: For some tracks we have large differences in value of chi
      square between ENGINE and hcana and this is already
      discussed in the last group meeting. Following emails are
      exchanged regarding this difference of chisquare.

email to Mark:

Hi Mark,
I tried to trace the origin of difference of the chi square value between
ENGINE and hcana. Please see the attached file, it has long table which I
cannot present in this email. Or you can see the file at the following
link, thanks.

https://userweb.jlab.org/~zahmed/chi2diff.txt

Ahmed

Mark's reply:
Ahmed,
        Thanks. I agree with what you see, but there is also another reason
for the difference. For the space point in ch2 the engine and hcana
choose different left/right combinations. That is why you see the large
jump in the summed chi2 from planes 9 and 10. The two codes pick
different left/right because there is a cut on the difference between the
measured stub xp and an expected xp = sp->GetX()/875  and one code has a combination
slightly below the cut value and the other slightly above. I do not see a way
to make the codes agree more exactly since the stub fitting involves a matrix
inversion.

                Cheers,
                       Mark

Goldent track is moved to THcHallCSpectrometer::TrackCalc()
  if  fSelUsingScin == 0 then golden track is calculated just
  like podd. i.e. it is the first track with minimum chi2/ndf
  with sorting ON

  if fSelUsingScin == 1 then golden track is calculetd just like
  engine/HTRACKING/h_select_best_track_using_scin.h. This method
  gives the best track with minimum value of chi2/ndf but with
  additional cuts on the tracks. These cuts are on dedx, beta
  and on energy.

  This commit also corrects and modifies the beta code written
  in the THcHodoscope::FineProcess

  At this point we have godlend track and in additoion to
  previous vlues the following values are set to a track:
  Energy, beta, chi2 of beta and dedx[track][first hit].

NOTE: For some tracks we have large differences in value of chi
      square between ENGINE and hcana and this is already
      discussed in the last group meeting. Following emails are
      exchanged regarding this difference of chisquare.

email to Mark:

Hi Mark,
I tried to trace the origin of difference of the chi square value between
ENGINE and hcana. Please see the attached file, it has long table which I
cannot present in this email. Or you can see the file at the following
link, thanks.

https://userweb.jlab.org/~zahmed/chi2diff.txt

Ahmed

Mark's reply:
Ahmed,
        Thanks. I agree with what you see, but there is also another reason
for the difference. For the space point in ch2 the engine and hcana
choose different left/right combinations. That is why you see the large
jump in the summed chi2 from planes 9 and 10. The two codes pick
different left/right because there is a cut on the difference between the
measured stub xp and an expected xp = sp->GetX()/875  and one code has a combination
slightly below the cut value and the other slightly above. I do not see a way
to make the codes agree more exactly since the stub fitting involves a matrix
inversion.

                Cheers,
                       Mark

Bugs fixed.

  Goldent track is moved to THcHallCSpectrometer::TrackCalc()
  if  fSelUsingScin == 0 then golden track is calculated just
  like podd. i.e. it is the first track with minimum chi2/ndf
  with sorting ON

  if fSelUsingScin == 1 then golden track is calculetd just like
  engine/HTRACKING/h_select_best_track_using_scin.h. This method
  gives the best track with minimum value of chi2/ndf but with
  additional cuts on the tracks. These cuts are on dedx, beta
  and on energy.

  This commit also corrects and modifies the beta code written
  in the THcHodoscope::FineProcess

  At this point we have godlend track and in additoion to
  previous vlues the following values are set to a track:
  Energy, beta, chi2 of beta and dedx[track][first hit].

NOTE: For some tracks we have large differences in value of chi
      square between ENGINE and hcana and this is already
      discussed in the last group meeting. Following emails are
      exchanged regarding this difference of chisquare.

email to Mark:

Hi Mark,
I tried to trace the origin of difference of the chi square value between
ENGINE and hcana. Please see the attached file, it has long table which I
cannot present in this email. Or you can see the file at the following
link, thanks.

https://userweb.jlab.org/~zahmed/chi2diff.txt

Ahmed

Mark's reply:
Ahmed,
        Thanks. I agree with what you see, but there is also another reason
for the difference. For the space point in ch2 the engine and hcana
choose different left/right combinations. That is why you see the large
jump in the summed chi2 from planes 9 and 10. The two codes pick
different left/right because there is a cut on the difference between the
measured stub xp and an expected xp = sp->GetX()/875  and one code has a combination
slightly below the cut value and the other slightly above. I do not see a way
to make the codes agree more exactly since the stub fitting involves a matrix
inversion.

                Cheers,
                       Mark

---------------------------------------------------------------------------------------

shower counter's FineProcess.

       Remove THcHallCSpectrometer::TrackEnergies method.
       Add GetShEnergy call for each tack in THcShower::fineProcess.

crashes.

    Add TrackEnergies method in THcHallCSpectrometer class. It is
    called from TrackCalc metod.

  Parameters are retrieved in THcHallCSpectrometer::ReadDatabase
  Geometry information saved with
     SetCentralAngles and fPointOffset.SetXYX

Add fTheta_lab
Do offsets in THcHallCSpectrometer::ReadDatabase

  Name of coefficient file in hcana.param
  Some basic hms setting parameters added to test.database for run 50017
  Traceback code in THcHalCSpectrometer

  Results are focal plane coordinate (transport) system, not detector system
  Turn on golden track selection.