TProfile2D

class TProfile2D : public TH2D

    private:

      Double_t* GetB()
      Double_t* GetW()
      Double_t* GetW2()

    public:

           TProfile2D TProfile2D()
           TProfile2D TProfile2D(const char* name, const char* title, Int_t nbinsx, Axis_t xlow, Axis_t xup, Int_t nbinsy, Axis_t ylow, Axis_t yup, Option_t* option)
           TProfile2D TProfile2D(const char* name, const char* title, Int_t nbinsx, Axis_t xlow, Axis_t xup, Int_t nbinsy, Axis_t ylow, Axis_t yup, Axis_t zlow, Axis_t zup, Option_t* option)
           TProfile2D TProfile2D(const TProfile2D& profile)
         virtual void ~TProfile2D()
         virtual void Add(TH1* h1, Float_t c1 = 1)
         virtual void Add(TH1* h1, TH1* h2, Float_t c1 = 1, Float_t c2 = 1)
                 void BuildOptions(Float_t zmin, Float_t zmax, Option_t* option)
       static TClass* Class()
         virtual void Copy(TObject& hnew)
         virtual void Divide(TH1* h1)
         virtual void Divide(TH1* h1, TH1* h2, Float_t c1 = 1, Float_t c2 = 1, Option_t* option)
         virtual TH1* DrawCopy(Option_t* option)
        virtual Int_t Fill(Axis_t)
        virtual Int_t Fill(Axis_t, Axis_t)
        virtual Int_t Fill(Axis_t, Stat_t)
        virtual Int_t Fill(Axis_t x, Axis_t y, Axis_t z)
        virtual Int_t Fill(Axis_t x, Axis_t y, Stat_t z)
        virtual Int_t Fill(Axis_t x, Axis_t y, Axis_t z, Stat_t w)
       virtual Stat_t GetBinContent(Int_t bin)
       virtual Stat_t GetBinEntries(Int_t bin)
       virtual Stat_t GetBinError(Int_t bin)
            Option_t* GetErrorOption() const
      virtual Float_t GetZmax()
      virtual Float_t GetZmin()
      virtual TClass* IsA() const
         virtual void Multiply(TH1* h1)
         virtual void Multiply(TH1* h1, TH1* h2, Float_t c1 = 1, Float_t c2 = 1, Option_t* option)
                TH2D* ProjectionXY(const char* name = _pxy, Option_t* option = e)
         virtual void Reset(Option_t* option)
         virtual void Scale(Float_t c1 = 1)
         virtual void SetBinEntries(Int_t bin, Stat_t w)
         virtual void SetBins(Int_t, Float_t, Float_t)
         virtual void SetBins(Int_t nbinsx, Float_t xmin, Float_t xmax, Int_t nbinsy, Float_t ymin, Float_t ymax)
         virtual void SetBins(Int_t, Float_t, Float_t, Int_t, Float_t, Float_t, Int_t, Float_t, Float_t)
         virtual void SetErrorOption(Option_t* option)
         virtual void ShowMembers(TMemberInspector& insp, char* parent)
         virtual void Streamer(TBuffer& b)

  Data Members

    protected:

         TArrayD fBinEntries  number of entries per bin
      EErrorType fErrorMode   Option to compute errors
         Float_t fZmin        Lower limit in Z (if set)
         Float_t fZmax        Upper limit in Z (if set)

Class Description

  Profile2D histograms are used to display the mean
  value of Z and its RMS for each cell in X,Y.
  Profile2D histograms are in many cases an
  elegant replacement of three-dimensional histograms : the inter-relation of three
  measured quantities X, Y and Z can always be visualized by a three-dimensional
  histogram or scatter-plot; its representation on the line-printer is not particularly
  satisfactory, except for sparse data. If Z is an unknown (but single-valued)
  approximate function of X,Y this function is displayed by a profile2D histogram with
  much better precision than by a scatter-plot.

  The following formulae show the cumulated contents (capital letters) and the values
  displayed by the printing or plotting routines (small letters) of the elements for cell I, J.

                                                        2
      H(I,J)  =  sum Z                  E(I,J)  =  sum Z
      l(I,J)  =  sum l                  L(I,J)  =  sum l
      h(I,J)  =  H(I,J)/L(I,J)          s(I,J)  =  sqrt(E(I,J)/L(I,J)- h(I,J)**2)
      e(I,J)  =  s(I,J)/sqrt(L(I,J))

  In the special case where s(I,J) is zero (eg, case of 1 entry only in one cell)
  e(I,J) is computed from the average of the s(I,J) for all cells.
  This simple/crude approximation was suggested in order to keep the cell
  during a fit operation.

           Example of a profile2D histogram
{
  TCanvas *c1 = new TCanvas("c1","Profile histogram example",200,10,700,500);
  hprof2d  = new TProfile2D("hprof2d","Profile of pz versus px and py",40,-4,4,40,-4,4,0,20);
  Float_t px, py, pz;
  for ( Int_t i=0; i<25000; i++) {
     gRandom->Rannor(px,py);
     pz = px*px + py*py;
     hprof2d->Fill(px,py,pz,1);
  }
  hprof2d->Draw();
}

*-*-*-*-*-*Default constructor for Profile2D histograms*-*-*-*-*-*-*-*-*
*-*        ============================================

*-*-*-*-*-*Default destructor for Profile2D histograms*-*-*-*-*-*-*-*-*
*-*        ===========================================

*-*-*-*-*-*Normal Constructor for Profile histograms*-*-*-*-*-*-*-*-*-*
*-*        ==========================================

  The first eight parameters are similar to TH2D::TH2D.
  All values of z are accepted at filling time.
  To fill a profile2D histogram, one must use TProfile2D::Fill function.

  Note that when filling the profile histogram the function Fill
  checks if the variable z is betyween fZmin and fZmax.
  If a minimum or maximum value is set for the Z scale before filling,
  then all values below zmin or above zmax will be discarded.
  Setting the minimum or maximum value for the Z scale before filling
  has the same effect as calling the special TProfile2D constructor below
  where zmin and zmax are specified.

  H(I,J) is printed as the cell contents. The errors computed are s(I,J) if CHOPT='S'
  (spread option), or e(I,J) if CHOPT=' ' (error on mean).

        See TProfile2D::BuildOptions for explanation of parameters

*-*-*-*-*-*Constructor for Profile2D histograms with range in z*-*-*-*-*-*
*-*        ====================================================
  The first eight parameters are similar to TH2D::TH2D.
  Only the values of Z between ZMIN and ZMAX will be considered at filling time.
  zmin and zmax will also be the maximum and minimum values
  on the z scale when drawing the profile2D.

        See TProfile2D::BuildOptions for more explanations on errors

*-*-*-*-*-*-*Set Profile2D histogram structure and options*-*-*-*-*-*-*-*-*
*-*          =============================================

    If a cell has N data points all with the same value Z (especially
    possible when dealing with integers), the spread in Z for that cell
    is zero, and the uncertainty assigned is also zero, and the cell is
    ignored in making subsequent fits. If SQRT(Z) was the correct error
    in the case above, then SQRT(Z)/SQRT(N) would be the correct error here.
    In fact, any cell with non-zero number of entries N but with zero spread
    should have an uncertainty SQRT(Z)/SQRT(N).

    Now, is SQRT(Z)/SQRT(N) really the correct uncertainty?
    that it is only in the case where the Z variable is some sort
    of counting statistics, following a Poisson distribution. This should
    probably be set as the default case. However, Z can be any variable
    from an original NTUPLE, not necessarily distributed "Poissonly".
    The computation of errors is based on the parameter option:
    option:
     ' '  (Default) Errors are Spread/SQRT(N) for Spread.ne.0. ,
                      "     "  SQRT(Z)/SQRT(N) for Spread.eq.0,N.gt.0 ,
                      "     "  0.  for N.eq.0
     's'            Errors are Spread  for Spread.ne.0. ,
                      "     "  SQRT(Z)  for Spread.eq.0,N.gt.0 ,
                      "     "  0.  for N.eq.0
     'i'            Errors are Spread/SQRT(N) for Spread.ne.0. ,
                      "     "  1./SQRT(12.*N) for Spread.eq.0,N.gt.0 ,
                      "     "  0.  for N.eq.0

    The third case above corresponds to Integer Z values for which the
    uncertainty is +-0.5, with the assumption that the probability that Z
    takes any value between Z-0.5 and Z+0.5 is uniform (the same argument
    goes for Z uniformly distributed between Z and Z+1); this would be
    useful if Z is an ADC measurement, for example. Other, fancier options
    would be possible, at the cost of adding one more parameter to the PROFILE2D
    For example, if all Z variables are distributed according to some
    known Gaussian of standard deviation Sigma, then:
     'G'            Errors are Spread/SQRT(N) for Spread.ne.0. ,
                      "     "  Sigma/SQRT(N) for Spread.eq.0,N.gt.0 ,
                      "     "  0.  for N.eq.0
    For example, this would be useful when all Z's are experimental quantities
    measured with the same instrument with precision Sigma.

 Performs the operation: this = this + c1*h1

*-*-*-*-*Replace contents of this profile2D by the addition of h1 and h2*-*-*
*-*      ===============================================================

   this = c1*h1 + c2*h2

*-*-*-*-*-*-*-*Copy a Profile2D histogram to a new profile2D histogram*-*-*-*
*-*            =======================================================

*-*-*-*-*-*-*-*-*-*-*Divide this profile2D by h1*-*-*-*-*-*-*-*-*-*-*-*-*
*-*                  ===========================

   this = this/h1

*-*-*-*-*Replace contents of this profile2D by the division of h1 by h2*-*-*
*-*      ==============================================================

   this = c1*h1/(c2*h2)

*-*-*-*-*-*-*-*Draw a copy of this profile2D histogram*-*-*-*-*-*-*-*-*-*-*
*-*            =======================================

*-*-*-*-*-*-*-*-*-*-*Fill a Profile2D histogram (no weights)*-*-*-*-*-*-*-*
*-*                  =======================================

*-*-*-*-*-*-*-*-*-*-*Fill a Profile2D histogram with weights*-*-*-*-*-*-*-*
*-*                  =======================================

*-*-*-*-*-*-*Return bin content of a Profile2D histogram*-*-*-*-*-*-*-*-*
*-*          ===========================================

*-*-*-*-*-*-*Return bin entries of a Profile2D histogram*-*-*-*-*-*-*-*-*
*-*          ===========================================

*-*-*-*-*-*-*Return bin error of a Profile2D histogram*-*-*-*-*-*-*-*-*
*-*          =========================================

*-*-*-*-*-*-*-*-*-*Return option to compute profile2D errors*-*-*-*-*-*-*-*
*-*                =========================================

*-*-*-*-*-*-*-*-*-*-*Multiply this profile2D by h1*-*-*-*-*-*-*-*-*-*-*-*
*-*                  =============================

   this = this*h1

*-*-*-*-*Replace contents of this profile2D by multiplication of h1 by h2*-*
*-*      ================================================================

   this = (c1*h1)*(c2*h2)

*-*-*-*-*Project this profile2D into a 2-D histogram along X,Y*-*-*-*-*-*-*
*-*      =====================================================

   The projection is always of the type TH2D.

   if option "E" is specified, the errors are computed. (default)

*-*-*-*-*-*-*-*-*-*Reset contents of a Profile2D histogram*-*-*-*-*-*-*-*
*-*                =======================================

*-*-*-*-*Multiply this profile2D by a constant c1*-*-*-*-*-*-*-*-*
*-*      ========================================

   this = c1*this

 This function uses the services of TProfile2D::Add

*-*-*-*-*-*-*-*-*Set the number of entries in bin*-*-*-*-*-*-*-*-*-*-*-*
*-*              ================================

*-*-*-*-*-*-*-*-*Redefine  x axis parameters*-*-*-*-*-*-*-*-*-*-*-*
*-*              ===========================

*-*-*-*-*-*-*-*-*-*Set option to compute profile2D errors*-*-*-*-*-*-*-*
*-*                =======================================

    The computation of errors is based on the parameter option:
    option:
     ' '  (Default) Errors are Spread/SQRT(N) for Spread.ne.0. ,
                      "     "  SQRT(Z)/SQRT(N) for Spread.eq.0,N.gt.0 ,
                      "     "  0.  for N.eq.0
     's'            Errors are Spread  for Spread.ne.0. ,
                      "     "  SQRT(Z)  for Spread.eq.0,N.gt.0 ,
                      "     "  0.  for N.eq.0
     'i'            Errors are Spread/SQRT(N) for Spread.ne.0. ,
                      "     "  1./SQRT(12.*N) for Spread.eq.0,N.gt.0 ,
                      "     "  0.  for N.eq.0
   See TProfile2D::BuildOptions for explanation of all options

Inline Functions

          Double_t* GetB()
          Double_t* GetW()
          Double_t* GetW2()
              Int_t Fill(Axis_t, Stat_t)
              Int_t Fill(Axis_t x, Axis_t y, Axis_t z)
              Int_t Fill(Axis_t x, Axis_t y, Stat_t z)
              Int_t Fill(Axis_t x, Axis_t y, Axis_t z, Stat_t w)
            Float_t GetZmin()
            Float_t GetZmax()
               void SetBins(Int_t nbinsx, Float_t xmin, Float_t xmax, Int_t nbinsy, Float_t ymin, Float_t ymax)
               void SetBins(Int_t, Float_t, Float_t, Int_t, Float_t, Float_t, Int_t, Float_t, Float_t)
            TClass* Class()
            TClass* IsA() const
               void ShowMembers(TMemberInspector& insp, char* parent)
               void Streamer(TBuffer& b)