// @(#)root/graf:$Name:  $:$Id: TGraphErrors.h,v 1.21 2005/03/07 09:15:45 brun Exp $
// Author: Rene Brun   15/09/96

/*************************************************************************
 * Copyright (C) 1995-2000, Rene Brun and Fons Rademakers.               *
 * All rights reserved.                                                  *
 *                                                                       *
 * For the licensing terms see $ROOTSYS/LICENSE.                         *
 * For the list of contributors see $ROOTSYS/README/CREDITS.             *
 *************************************************************************/

#ifndef ROOT_TGraphErrors
#define ROOT_TGraphErrors


//////////////////////////////////////////////////////////////////////////
//                                                                      //
// TGraphErrors                                                         //
//                                                                      //
// a Graph with error bars                                              //
//                                                                      //
//////////////////////////////////////////////////////////////////////////

#ifndef ROOT_TGraph
#include "TGraph.h"
#endif

class TGraphErrors : public TGraph {

protected:
    Double_t    *fEX;        //[fNpoints] array of X errors
    Double_t    *fEY;        //[fNpoints] array of Y errors

    virtual void     SwapPoints(Int_t pos1, Int_t pos2);

   virtual Double_t** Allocate(Int_t size);
   virtual void       CopyAndRelease(Double_t **newarrays,
                                     Int_t ibegin, Int_t iend, Int_t obegin);
   virtual Bool_t     CopyPoints(Double_t **arrays, Int_t ibegin, Int_t iend,
                                 Int_t obegin);
           Bool_t     CtorAllocate();
   virtual void       FillZero(Int_t begin, Int_t end,
                               Bool_t from_ctor = kTRUE);

public:
        TGraphErrors();
        TGraphErrors(Int_t n);
        TGraphErrors(Int_t n, const Float_t *x, const Float_t *y, const Float_t *ex=0, const Float_t *ey=0);
        TGraphErrors(Int_t n, const Double_t *x, const Double_t *y, const Double_t *ex=0, const Double_t *ey=0);
        TGraphErrors(const TVector  &vx, const TVector  &vy, const TVector  &vex, const TVector  &vey);
        TGraphErrors(const TVectorD &vx, const TVectorD &vy, const TVectorD &vex, const TVectorD &vey);
        TGraphErrors(const TGraphErrors &gr);
        TGraphErrors(const TH1 *h);
        TGraphErrors(const char *filename, const char *format="%lg %lg %lg %lg", Option_t *option="");
        virtual ~TGraphErrors();
        virtual void    Apply(TF1 *f);
        static Int_t    CalculateScanfFields(const char *fmt);
        virtual void    ComputeRange(Double_t &xmin, Double_t &ymin, Double_t &xmax, Double_t &ymax) const;
        Double_t        GetErrorX(Int_t bin)     const;
        Double_t        GetErrorY(Int_t bin)     const;
	Double_t        GetErrorXhigh(Int_t bin) const;
	Double_t        GetErrorXlow(Int_t bin)  const;
	Double_t        GetErrorYhigh(Int_t bin) const;
	Double_t        GetErrorYlow(Int_t bin)  const;
        Double_t       *GetEX() const {return fEX;}
        Double_t       *GetEY() const {return fEY;}
        virtual void    Paint(Option_t *chopt="");
        virtual void    Print(Option_t *chopt="") const;
        virtual void    SavePrimitive(ofstream &out, Option_t *option);
        virtual void    SetPointError(Double_t ex, Double_t ey);  // *MENU
        virtual void    SetPointError(Int_t i, Double_t ex, Double_t ey);

        ClassDef(TGraphErrors,3)  //A graph with error bars
};

inline Double_t **TGraphErrors::Allocate(Int_t size) {
   return AllocateArrays(4, size);
}

#endif