// @(#)root/hist:$Id: TH3.cxx 26511 2008-11-28 15:35:51Z moneta $
// Author: Rene Brun   27/10/95

/*************************************************************************
 * 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.             *
 *************************************************************************/

#include "TROOT.h"
#include "TClass.h"
#include "THashList.h"
#include "TH3.h"
#include "TProfile2D.h"
#include "TH2.h"
#include "TF1.h"
#include "TVirtualPad.h"
#include "TVirtualHistPainter.h"
#include "THLimitsFinder.h"
#include "TRandom.h"
#include "TError.h"
#include "TMath.h"
#include "TObjString.h"

ClassImp(TH3)

//______________________________________________________________________________
//*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
//*-*
//*-*  The 3-D histogram classes derived from the 1-D histogram classes.
//*-*  all operations are supported (fill, fit).
//*-*  Drawing is currently restricted to one single option.
//*-*  A cloud of points is drawn. The number of points is proportional to
//*-*  cell content.
//*-*
//
//  TH3C a 3-D histogram with one byte per cell (char)
//  TH3S a 3-D histogram with two bytes per cell (short integer)
//  TH3I a 3-D histogram with four bytes per cell (32 bits integer)
//  TH3F a 3-D histogram with four bytes per cell (float)
//  TH3D a 3-D histogram with eight bytes per cell (double)
//
//*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

//______________________________________________________________________________
TH3::TH3()
{
   // Default constructor.
   fDimension   = 3;
   fTsumwy      = fTsumwy2 = fTsumwxy = 0;
   fTsumwz      = fTsumwz2 = fTsumwxz = fTsumwyz = 0;
   SetBinsLength(27);
}

//______________________________________________________________________________
TH3::TH3(const char *name,const char *title,Int_t nbinsx,Double_t xlow,Double_t xup
                                     ,Int_t nbinsy,Double_t ylow,Double_t yup
                                     ,Int_t nbinsz,Double_t zlow,Double_t zup)
     :TH1(name,title,nbinsx,xlow,xup),
      TAtt3D()
{
//*-*-*-*-*-*-*-*-*Normal constructor for fix bin size 3-D histograms*-*-*-*-*
//*-*              ==================================================

   fDimension   = 3;
   if (nbinsy <= 0) nbinsy = 1;
   if (nbinsz <= 0) nbinsz = 1;
   fYaxis.Set(nbinsy,ylow,yup);
   fZaxis.Set(nbinsz,zlow,zup);
   fNcells      = (nbinsx+2)*(nbinsy+2)*(nbinsz+2);
   fTsumwy      = fTsumwy2 = fTsumwxy = 0;
   fTsumwz      = fTsumwz2 = fTsumwxz = fTsumwyz = 0;
}

//______________________________________________________________________________
TH3::TH3(const char *name,const char *title,Int_t nbinsx,const Float_t *xbins
                                           ,Int_t nbinsy,const Float_t *ybins
                                           ,Int_t nbinsz,const Float_t *zbins)
     :TH1(name,title,nbinsx,xbins),
      TAtt3D()
{
//*-*-*-*-*-*-*-*Normal constructor for variable bin size 3-D histograms*-*-*-*
//*-*            =======================================================
   fDimension   = 3;
   if (nbinsy <= 0) nbinsy = 1;
   if (nbinsz <= 0) nbinsz = 1;
   if (ybins) fYaxis.Set(nbinsy,ybins);
   else       fYaxis.Set(nbinsy,0,1);
   if (zbins) fZaxis.Set(nbinsz,zbins);
   else       fZaxis.Set(nbinsz,0,1);
   fNcells      = (nbinsx+2)*(nbinsy+2)*(nbinsz+2);
   fTsumwy      = fTsumwy2 = fTsumwxy = 0;
   fTsumwz      = fTsumwz2 = fTsumwxz = fTsumwyz = 0;
}

//______________________________________________________________________________
TH3::TH3(const char *name,const char *title,Int_t nbinsx,const Double_t *xbins
                                           ,Int_t nbinsy,const Double_t *ybins
                                           ,Int_t nbinsz,const Double_t *zbins)
     :TH1(name,title,nbinsx,xbins),
      TAtt3D()
{
//*-*-*-*-*-*-*-*Normal constructor for variable bin size 3-D histograms*-*-*-*
//*-*            =======================================================
   fDimension   = 3;
   if (nbinsy <= 0) nbinsy = 1;
   if (nbinsz <= 0) nbinsz = 1;
   if (ybins) fYaxis.Set(nbinsy,ybins);
   else       fYaxis.Set(nbinsy,0,1);
   if (zbins) fZaxis.Set(nbinsz,zbins);
   else       fZaxis.Set(nbinsz,0,1);
   fNcells      = (nbinsx+2)*(nbinsy+2)*(nbinsz+2);
   fTsumwy      = fTsumwy2 = fTsumwxy = 0;
   fTsumwz      = fTsumwz2 = fTsumwxz = fTsumwyz = 0;
}

//______________________________________________________________________________
TH3::TH3(const TH3 &h) : TH1(), TAtt3D()
{
   // Copy constructor.
   // The list of functions is not copied. (Use Clone if needed)

   ((TH3&)h).Copy(*this);
}

//______________________________________________________________________________
TH3::~TH3()
{
   // Destructor.
}

//______________________________________________________________________________
void TH3::Copy(TObject &obj) const
{
   // Copy.

   TH1::Copy(obj);
   ((TH3&)obj).fTsumwy      = fTsumwy;
   ((TH3&)obj).fTsumwy2     = fTsumwy2;
   ((TH3&)obj).fTsumwxy     = fTsumwxy;
   ((TH3&)obj).fTsumwz      = fTsumwz;
   ((TH3&)obj).fTsumwz2     = fTsumwz2;
   ((TH3&)obj).fTsumwxz     = fTsumwxz;
   ((TH3&)obj).fTsumwyz     = fTsumwyz;
}

//______________________________________________________________________________
Int_t TH3::BufferEmpty(Int_t action)
{
   // Fill histogram with all entries in the buffer.
   // action = -1 histogram is reset and refilled from the buffer (called by THistPainter::Paint)
   // action =  0 histogram is filled from the buffer
   // action =  1 histogram is filled and buffer is deleted
   //             The buffer is automatically deleted when the number of entries
   //             in the buffer is greater than the number of entries in the histogram

   // do we need to compute the bin size?
   if (!fBuffer) return 0;
   Int_t nbentries = (Int_t)fBuffer[0];
   if (!nbentries) return 0;
   Double_t *buffer = fBuffer;
   if (nbentries < 0) {
      if (action == 0) return 0;
      nbentries  = -nbentries;
      fBuffer=0;
      Reset();
      fBuffer = buffer;
   }
   if (TestBit(kCanRebin) || fXaxis.GetXmax() <= fXaxis.GetXmin() ||
      fYaxis.GetXmax() <= fYaxis.GetXmin() ||
      fZaxis.GetXmax() <= fZaxis.GetXmin()) {
         //find min, max of entries in buffer
         Double_t xmin = fBuffer[2];
         Double_t xmax = xmin;
         Double_t ymin = fBuffer[3];
         Double_t ymax = ymin;
         Double_t zmin = fBuffer[4];
         Double_t zmax = zmin;
         for (Int_t i=1;i<nbentries;i++) {
            Double_t x = fBuffer[4*i+2];
            if (x < xmin) xmin = x;
            if (x > xmax) xmax = x;
            Double_t y = fBuffer[4*i+3];
            if (y < ymin) ymin = y;
            if (y > ymax) ymax = y;
            Double_t z = fBuffer[4*i+4];
            if (z < zmin) zmin = z;
            if (z > zmax) zmax = z;
         }
         if (fXaxis.GetXmax() <= fXaxis.GetXmin() || fYaxis.GetXmax() <= fYaxis.GetXmin() || fZaxis.GetXmax() <= fZaxis.GetXmin()) {
            THLimitsFinder::GetLimitsFinder()->FindGoodLimits(this,xmin,xmax,ymin,ymax,zmin,zmax);
         } else {
            fBuffer = 0;
            Int_t keep = fBufferSize; fBufferSize = 0;
            if (xmin <  fXaxis.GetXmin()) RebinAxis(xmin,&fXaxis);
            if (xmax >= fXaxis.GetXmax()) RebinAxis(xmax,&fXaxis);
            if (ymin <  fYaxis.GetXmin()) RebinAxis(ymin,&fYaxis);
            if (ymax >= fYaxis.GetXmax()) RebinAxis(ymax,&fYaxis);
            if (zmin <  fZaxis.GetXmin()) RebinAxis(zmin,&fZaxis);
            if (zmax >= fZaxis.GetXmax()) RebinAxis(zmax,&fZaxis);
            fBuffer = buffer;
            fBufferSize = keep;
         }
   }
   fBuffer = 0;

   for (Int_t i=0;i<nbentries;i++) {
      Fill(buffer[4*i+2],buffer[4*i+3],buffer[4*i+4],buffer[4*i+1]);
   }
   fBuffer = buffer;

   if (action > 0) { delete [] fBuffer; fBuffer = 0; fBufferSize = 0;}
   else {
      if (nbentries == (Int_t)fEntries) fBuffer[0] = -nbentries;
      else                              fBuffer[0] = 0;
   }
   return nbentries;
}

//______________________________________________________________________________
Int_t TH3::BufferFill(Double_t x, Double_t y, Double_t z, Double_t w)
{
   // accumulate arguments in buffer. When buffer is full, empty the buffer
   // fBuffer[0] = number of entries in buffer
   // fBuffer[1] = w of first entry
   // fBuffer[2] = x of first entry
   // fBuffer[3] = y of first entry
   // fBuffer[4] = z of first entry

   if (!fBuffer) return -3;
   Int_t nbentries = (Int_t)fBuffer[0];
   if (nbentries < 0) {
      nbentries  = -nbentries;
      fBuffer[0] =  nbentries;
      if (fEntries > 0) {
         Double_t *buffer = fBuffer; fBuffer=0;
         Reset();
         fBuffer = buffer;
      }
   }
   if (4*nbentries+4 >= fBufferSize) {
      BufferEmpty(1);
      return Fill(x,y,z,w);
   }
   fBuffer[4*nbentries+1] = w;
   fBuffer[4*nbentries+2] = x;
   fBuffer[4*nbentries+3] = y;
   fBuffer[4*nbentries+4] = z;
   fBuffer[0] += 1;
   return -3;
}

//______________________________________________________________________________
Int_t TH3::Fill(Double_t x, Double_t y, Double_t z)
{
   //*-*-*-*-*-*-*-*-*-*-*Increment cell defined by x,y,z by 1 *-*-*-*-*
   //*-*                  ====================================
   //*-*
   //*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

   if (fBuffer) return BufferFill(x,y,z,1);

   Int_t binx, biny, binz, bin;
   fEntries++;
   binx = fXaxis.FindBin(x);
   biny = fYaxis.FindBin(y);
   binz = fZaxis.FindBin(z);
   bin  =  binx + (fXaxis.GetNbins()+2)*(biny + (fYaxis.GetNbins()+2)*binz);
   AddBinContent(bin);
   if (fSumw2.fN) ++fSumw2.fArray[bin];
   if (binx == 0 || binx > fXaxis.GetNbins()) {
      if (!fgStatOverflows) return -1;
   }

   if (biny == 0 || biny > fYaxis.GetNbins()) {
      if (!fgStatOverflows) return -1;
   }
   if (binz == 0 || binz > fZaxis.GetNbins()) {
      if (!fgStatOverflows) return -1;
   }
   ++fTsumw;
   ++fTsumw2;
   fTsumwx  += x;
   fTsumwx2 += x*x;
   fTsumwy  += y;
   fTsumwy2 += y*y;
   fTsumwxy += x*y;
   fTsumwz  += z;
   fTsumwz2 += z*z;
   fTsumwxz += x*z;
   fTsumwyz += y*z;
   return bin;
}

//______________________________________________________________________________
Int_t TH3::Fill(Double_t x, Double_t y, Double_t z, Double_t w)
{
   //*-*-*-*-*-*-*-*-*-*-*Increment cell defined by x,y,z by a weight w*-*-*-*-*
   //*-*                  =============================================
   //*-*
   //*-* If the storage of the sum of squares of weights has been triggered,
   //*-* via the function Sumw2, then the sum of the squares of weights is incremented
   //*-* by w^2 in the cell corresponding to x,y,z.
   //*-*
   //*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

   if (fBuffer) return BufferFill(x,y,z,w);

   Int_t binx, biny, binz, bin;
   fEntries++;
   binx = fXaxis.FindBin(x);
   biny = fYaxis.FindBin(y);
   binz = fZaxis.FindBin(z);
   bin  =  binx + (fXaxis.GetNbins()+2)*(biny + (fYaxis.GetNbins()+2)*binz);
   AddBinContent(bin,w);
   if (fSumw2.fN) fSumw2.fArray[bin] += w*w;
   if (binx == 0 || binx > fXaxis.GetNbins()) {
      if (!fgStatOverflows) return -1;
   }
   if (biny == 0 || biny > fYaxis.GetNbins()) {
      if (!fgStatOverflows) return -1;
   }
   if (binz == 0 || binz > fZaxis.GetNbins()) {
      if (!fgStatOverflows) return -1;
   }
   fTsumw   += w;
   fTsumw2  += w*w;
   fTsumwx  += w*x;
   fTsumwx2 += w*x*x;
   fTsumwy  += w*y;
   fTsumwy2 += w*y*y;
   fTsumwxy += w*x*y;
   fTsumwz  += w*z;
   fTsumwz2 += w*z*z;
   fTsumwxz += w*x*z;
   fTsumwyz += w*y*z;
   return bin;
}

//______________________________________________________________________________
Int_t TH3::Fill(const char *namex, const char *namey, const char *namez, Double_t w)
{
   // Increment cell defined by namex,namey,namez by a weight w
   //
   // If the storage of the sum of squares of weights has been triggered,
   // via the function Sumw2, then the sum of the squares of weights is incremented
   // by w^2 in the cell corresponding to x,y,z.
   //
   Int_t binx, biny, binz, bin;
   fEntries++;
   binx = fXaxis.FindBin(namex);
   biny = fYaxis.FindBin(namey);
   binz = fZaxis.FindBin(namez);
   bin  =  binx + (fXaxis.GetNbins()+2)*(biny + (fYaxis.GetNbins()+2)*binz);
   AddBinContent(bin,w);
   if (fSumw2.fN) fSumw2.fArray[bin] += w*w;
   if (binx == 0 || binx > fXaxis.GetNbins()) return -1;
   if (biny == 0 || biny > fYaxis.GetNbins()) return -1;
   if (binz == 0 || binz > fZaxis.GetNbins()) return -1;
   Double_t x = fXaxis.GetBinCenter(binx);
   Double_t y = fYaxis.GetBinCenter(biny);
   Double_t z = fZaxis.GetBinCenter(binz);
   Double_t v = (w > 0 ? w : -w);
   fTsumw   += v;
   fTsumw2  += v*v;
   fTsumwx  += v*x;
   fTsumwx2 += v*x*x;
   fTsumwy  += v*y;
   fTsumwy2 += v*y*y;
   fTsumwxy += v*x*y;
   fTsumwz  += v*z;
   fTsumwz2 += v*z*z;
   fTsumwxz += v*x*z;
   fTsumwyz += v*y*z;
   return bin;
}

//______________________________________________________________________________
Int_t TH3::Fill(const char *namex, Double_t y, const char *namez, Double_t w)
{
   // Increment cell defined by namex,y,namez by a weight w
   //
   // If the storage of the sum of squares of weights has been triggered,
   // via the function Sumw2, then the sum of the squares of weights is incremented
   // by w^2 in the cell corresponding to x,y,z.
   //
   Int_t binx, biny, binz, bin;
   fEntries++;
   binx = fXaxis.FindBin(namex);
   biny = fYaxis.FindBin(y);
   binz = fZaxis.FindBin(namez);
   bin  =  binx + (fXaxis.GetNbins()+2)*(biny + (fYaxis.GetNbins()+2)*binz);
   AddBinContent(bin,w);
   if (fSumw2.fN) fSumw2.fArray[bin] += w*w;
   if (binx == 0 || binx > fXaxis.GetNbins()) return -1;
   if (biny == 0 || biny > fYaxis.GetNbins()) {
      if (!fgStatOverflows) return -1;
   }
   if (binz == 0 || binz > fZaxis.GetNbins()) return -1;
   Double_t x = fXaxis.GetBinCenter(binx);
   Double_t z = fZaxis.GetBinCenter(binz);
   Double_t v = (w > 0 ? w : -w);
   fTsumw   += v;
   fTsumw2  += v*v;
   fTsumwx  += v*x;
   fTsumwx2 += v*x*x;
   fTsumwy  += v*y;
   fTsumwy2 += v*y*y;
   fTsumwxy += v*x*y;
   fTsumwz  += v*z;
   fTsumwz2 += v*z*z;
   fTsumwxz += v*x*z;
   fTsumwyz += v*y*z;
   return bin;
}

//______________________________________________________________________________
Int_t TH3::Fill(const char *namex, const char *namey, Double_t z, Double_t w)
{
   // Increment cell defined by namex,namey,z by a weight w
   //
   // If the storage of the sum of squares of weights has been triggered,
   // via the function Sumw2, then the sum of the squares of weights is incremented
   // by w^2 in the cell corresponding to x,y,z.
   //
   Int_t binx, biny, binz, bin;
   fEntries++;
   binx = fXaxis.FindBin(namex);
   biny = fYaxis.FindBin(namey);
   binz = fZaxis.FindBin(z);
   bin  =  binx + (fXaxis.GetNbins()+2)*(biny + (fYaxis.GetNbins()+2)*binz);
   AddBinContent(bin,w);
   if (fSumw2.fN) fSumw2.fArray[bin] += w*w;
   if (binx == 0 || binx > fXaxis.GetNbins()) return -1;
   if (biny == 0 || biny > fYaxis.GetNbins()) return -1;
   if (binz == 0 || binz > fZaxis.GetNbins()) {
      if (!fgStatOverflows) return -1;
   }
   Double_t x = fXaxis.GetBinCenter(binx);
   Double_t y = fYaxis.GetBinCenter(biny);
   Double_t v = (w > 0 ? w : -w);
   fTsumw   += v;
   fTsumw2  += v*v;
   fTsumwx  += v*x;
   fTsumwx2 += v*x*x;
   fTsumwy  += v*y;
   fTsumwy2 += v*y*y;
   fTsumwxy += v*x*y;
   fTsumwz  += v*z;
   fTsumwz2 += v*z*z;
   fTsumwxz += v*x*z;
   fTsumwyz += v*y*z;
   return bin;
}

//______________________________________________________________________________
Int_t TH3::Fill(Double_t x, const char *namey, const char *namez, Double_t w)
{
   // Increment cell defined by x,namey,namezz by a weight w
   //
   // If the storage of the sum of squares of weights has been triggered,
   // via the function Sumw2, then the sum of the squares of weights is incremented
   // by w^2 in the cell corresponding to x,y,z.
   //
   Int_t binx, biny, binz, bin;
   fEntries++;
   binx = fXaxis.FindBin(x);
   biny = fYaxis.FindBin(namey);
   binz = fZaxis.FindBin(namez);
   bin  =  binx + (fXaxis.GetNbins()+2)*(biny + (fYaxis.GetNbins()+2)*binz);
   AddBinContent(bin,w);
   if (fSumw2.fN) fSumw2.fArray[bin] += w*w;
   if (binx == 0 || binx > fXaxis.GetNbins()) {
      if (!fgStatOverflows) return -1;
   }
   if (biny == 0 || biny > fYaxis.GetNbins()) return -1;
   if (binz == 0 || binz > fZaxis.GetNbins()) return -1;
   Double_t y = fYaxis.GetBinCenter(biny);
   Double_t z = fZaxis.GetBinCenter(binz);
   Double_t v = (w > 0 ? w : -w);
   fTsumw   += v;
   fTsumw2  += v*v;
   fTsumwx  += v*x;
   fTsumwx2 += v*x*x;
   fTsumwy  += v*y;
   fTsumwy2 += v*y*y;
   fTsumwxy += v*x*y;
   fTsumwz  += v*z;
   fTsumwz2 += v*z*z;
   fTsumwxz += v*x*z;
   fTsumwyz += v*y*z;
   return bin;
}

//______________________________________________________________________________
Int_t TH3::Fill(Double_t x, const char *namey, Double_t z, Double_t w)
{
   // Increment cell defined by x,namey,z by a weight w
   //
   // If the storage of the sum of squares of weights has been triggered,
   // via the function Sumw2, then the sum of the squares of weights is incremented
   // by w^2 in the cell corresponding to x,y,z.
   //
   Int_t binx, biny, binz, bin;
   fEntries++;
   binx = fXaxis.FindBin(x);
   biny = fYaxis.FindBin(namey);
   binz = fZaxis.FindBin(z);
   bin  =  binx + (fXaxis.GetNbins()+2)*(biny + (fYaxis.GetNbins()+2)*binz);
   AddBinContent(bin,w);
   if (fSumw2.fN) fSumw2.fArray[bin] += w*w;
   if (binx == 0 || binx > fXaxis.GetNbins()) {
      if (!fgStatOverflows) return -1;
   }
   if (biny == 0 || biny > fYaxis.GetNbins()) return -1;
   if (binz == 0 || binz > fZaxis.GetNbins()) {
      if (!fgStatOverflows) return -1;
   }
   Double_t y = fYaxis.GetBinCenter(biny);
   Double_t v = (w > 0 ? w : -w);
   fTsumw   += v;
   fTsumw2  += v*v;
   fTsumwx  += v*x;
   fTsumwx2 += v*x*x;
   fTsumwy  += v*y;
   fTsumwy2 += v*y*y;
   fTsumwxy += v*x*y;
   fTsumwz  += v*z;
   fTsumwz2 += v*z*z;
   fTsumwxz += v*x*z;
   fTsumwyz += v*y*z;
   return bin;
}

//______________________________________________________________________________
Int_t TH3::Fill(Double_t x, Double_t y, const char *namez, Double_t w)
{
   // Increment cell defined by x,y,namez by a weight w
   //
   // If the storage of the sum of squares of weights has been triggered,
   // via the function Sumw2, then the sum of the squares of weights is incremented
   // by w^2 in the cell corresponding to x,y,z.
   //
   Int_t binx, biny, binz, bin;
   fEntries++;
   binx = fXaxis.FindBin(x);
   biny = fYaxis.FindBin(y);
   binz = fZaxis.FindBin(namez);
   bin  =  binx + (fXaxis.GetNbins()+2)*(biny + (fYaxis.GetNbins()+2)*binz);
   AddBinContent(bin,w);
   if (fSumw2.fN) fSumw2.fArray[bin] += w*w;
   if (binx == 0 || binx > fXaxis.GetNbins()) {
      if (!fgStatOverflows) return -1;
   }
   if (biny == 0 || biny > fYaxis.GetNbins()) {
      if (!fgStatOverflows) return -1;
   }
   if (binz == 0 || binz > fZaxis.GetNbins()) return -1;
   Double_t z = fZaxis.GetBinCenter(binz);
   Double_t v = (w > 0 ? w : -w);
   fTsumw   += v;
   fTsumw2  += v*v;
   fTsumwx  += v*x;
   fTsumwx2 += v*x*x;
   fTsumwy  += v*y;
   fTsumwy2 += v*y*y;
   fTsumwxy += v*x*y;
   fTsumwz  += v*z;
   fTsumwz2 += v*z*z;
   fTsumwxz += v*x*z;
   fTsumwyz += v*y*z;
   return bin;
}

//______________________________________________________________________________
void TH3::FillRandom(const char *fname, Int_t ntimes)
{
   //*-*-*-*-*-*-*Fill histogram following distribution in function fname*-*-*-*
   //*-*          =======================================================
   //*-*
   //*-*   The distribution contained in the function fname (TF1) is integrated
   //*-*   over the channel contents.
   //*-*   It is normalized to 1.
   //*-*   Getting one random number implies:
   //*-*     - Generating a random number between 0 and 1 (say r1)
   //*-*     - Look in which bin in the normalized integral r1 corresponds to
   //*-*     - Fill histogram channel
   //*-*   ntimes random numbers are generated
   //*-*
   //*-*  One can also call TF1::GetRandom to get a random variate from a function.
   //*-*
   //*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-**-*-*-*-*-*-*-*

   Int_t bin, binx, biny, binz, ibin, loop;
   Double_t r1, x, y,z, xv[3];
   //*-*- Search for fname in the list of ROOT defined functions
   TF1 *f1 = (TF1*)gROOT->GetFunction(fname);
   if (!f1) { Error("FillRandom", "Unknown function: %s",fname); return; }

   //*-*- Allocate temporary space to store the integral and compute integral
   Int_t nbinsx = GetNbinsX();
   Int_t nbinsy = GetNbinsY();
   Int_t nbinsz = GetNbinsZ();
   Int_t nxy    = nbinsx*nbinsy;
   Int_t nbins  = nxy*nbinsz;

   Double_t *integral = new Double_t[nbins+1];
   ibin = 0;
   integral[ibin] = 0;
   for (binz=1;binz<=nbinsz;binz++) {
      xv[2] = fZaxis.GetBinCenter(binz);
      for (biny=1;biny<=nbinsy;biny++) {
         xv[1] = fYaxis.GetBinCenter(biny);
         for (binx=1;binx<=nbinsx;binx++) {
            xv[0] = fXaxis.GetBinCenter(binx);
            ibin++;
            integral[ibin] = integral[ibin-1] + f1->Eval(xv[0],xv[1],xv[2]);
         }
      }
   }

   //*-*- Normalize integral to 1
   if (integral[nbins] == 0 ) {
      Error("FillRandom", "Integral = zero"); return;
   }
   for (bin=1;bin<=nbins;bin++)  integral[bin] /= integral[nbins];

   //*-*--------------Start main loop ntimes
   if (fDimension < 2) nbinsy = -1;
   if (fDimension < 3) nbinsz = -1;
   for (loop=0;loop<ntimes;loop++) {
      r1 = gRandom->Rndm(loop);
      ibin = TMath::BinarySearch(nbins,&integral[0],r1);
      binz = ibin/nxy;
      biny = (ibin - nxy*binz)/nbinsx;
      binx = 1 + ibin - nbinsx*(biny + nbinsy*binz);
      if (nbinsz) binz++;
      if (nbinsy) biny++;
      x    = fXaxis.GetBinCenter(binx);
      y    = fYaxis.GetBinCenter(biny);
      z    = fZaxis.GetBinCenter(binz);
      Fill(x,y,z, 1.);
   }
   delete [] integral;
}

//______________________________________________________________________________
void TH3::FillRandom(TH1 *h, Int_t ntimes)
{
   //*-*-*-*-*-*-*Fill histogram following distribution in histogram h*-*-*-*
   //*-*          ====================================================
   //*-*
   //*-*   The distribution contained in the histogram h (TH3) is integrated
   //*-*   over the channel contents.
   //*-*   It is normalized to 1.
   //*-*   Getting one random number implies:
   //*-*     - Generating a random number between 0 and 1 (say r1)
   //*-*     - Look in which bin in the normalized integral r1 corresponds to
   //*-*     - Fill histogram channel
   //*-*   ntimes random numbers are generated
   //*-*
   //*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-**-*-*-*-*-*-*-*

   if (!h) { Error("FillRandom", "Null histogram"); return; }
   if (fDimension != h->GetDimension()) {
      Error("FillRandom", "Histograms with different dimensions"); return;
   }

   if (h->ComputeIntegral() == 0) return;

   TH3 *h3 = (TH3*)h;
   Int_t loop;
   Double_t x,y,z;
   for (loop=0;loop<ntimes;loop++) {
      h3->GetRandom3(x,y,z);
      Fill(x,y,z,1.);
   }
}


//______________________________________________________________________________
void TH3::FitSlicesZ(TF1 *f1, Int_t binminx, Int_t binmaxx, Int_t binminy, Int_t binmaxy, Int_t cut, Option_t *option)
{
   // Project slices along Z in case of a 3-D histogram, then fit each slice
   // with function f1 and make a 2-d histogram for each fit parameter
   // Only cells in the bin range [binminx,binmaxx] and [binminy,binmaxy] are considered.
   // if f1=0, a gaussian is assumed
   // Before invoking this function, one can set a subrange to be fitted along Z
   // via f1->SetRange(zmin,zmax)
   // The argument option (default="QNR") can be used to change the fit options.
   //     "Q" means Quiet mode
   //     "N" means do not show the result of the fit
   //     "R" means fit the function in the specified function range
   //
   // Note that the generated histograms are added to the list of objects
   // in the current directory. It is the user's responsability to delete
   // these histograms.
   //
   //  Example: Assume a 3-d histogram h3
   //   Root > h3->FitSlicesZ(); produces 4 TH2D histograms
   //          with h3_0 containing parameter 0(Constant) for a Gaus fit
   //                    of each cell in X,Y projected along Z
   //          with h3_1 containing parameter 1(Mean) for a gaus fit
   //          with h3_2 containing parameter 2(RMS)  for a gaus fit
   //          with h3_chi2 containing the chisquare/number of degrees of freedom for a gaus fit
   //
   //   Root > h3->Fit(0,15,22,0,0,10);
   //          same as above, but only for bins 15 to 22 along X
   //          and only for cells in X,Y for which the corresponding projection
   //          along Z has more than cut bins filled.
   //
   //  NOTE: To access the generated histograms in the current directory, do eg:
   //     TH2D *h3_1 = (TH2D*)gDirectory->Get("h3_1");

   Int_t nbinsx  = fXaxis.GetNbins();
   Int_t nbinsy  = fYaxis.GetNbins();
   Int_t nbinsz  = fZaxis.GetNbins();
   if (binminx < 1) binminx = 1;
   if (binmaxx > nbinsx) binmaxx = nbinsx;
   if (binmaxx < binminx) {binminx = 1; binmaxx = nbinsx;}
   if (binminy < 1) binminy = 1;
   if (binmaxy > nbinsy) binmaxy = nbinsy;
   if (binmaxy < binminy) {binminy = 1; binmaxy = nbinsy;}

   //default is to fit with a gaussian
   if (f1 == 0) {
      f1 = (TF1*)gROOT->GetFunction("gaus");
      if (f1 == 0) f1 = new TF1("gaus","gaus",fZaxis.GetXmin(),fZaxis.GetXmax());
      else         f1->SetRange(fZaxis.GetXmin(),fZaxis.GetXmax());
   }
   const char *fname = f1->GetName();
   Int_t npar = f1->GetNpar();
   Double_t *parsave = new Double_t[npar];
   f1->GetParameters(parsave);

   //Create one 2-d histogram for each function parameter
   Int_t ipar;
   char name[80], title[80];
   TH2D *hlist[25];
   const TArrayD *xbins = fXaxis.GetXbins();
   const TArrayD *ybins = fYaxis.GetXbins();
   for (ipar=0;ipar<npar;ipar++) {
      sprintf(name,"%s_%d",GetName(),ipar);
      sprintf(title,"Fitted value of par[%d]=%s",ipar,f1->GetParName(ipar));
      if (xbins->fN == 0) {
         hlist[ipar] = new TH2D(name, title,
                                nbinsx, fXaxis.GetXmin(), fXaxis.GetXmax(),
                                nbinsy, fYaxis.GetXmin(), fYaxis.GetXmax());
      } else {
         hlist[ipar] = new TH2D(name, title,
                                nbinsx, xbins->fArray,
                                nbinsy, ybins->fArray);
      }
      hlist[ipar]->GetXaxis()->SetTitle(fXaxis.GetTitle());
      hlist[ipar]->GetYaxis()->SetTitle(fYaxis.GetTitle());
   }
   sprintf(name,"%s_chi2",GetName());
   TH2D *hchi2 = new TH2D(name,"chisquare", nbinsx, fXaxis.GetXmin(), fXaxis.GetXmax()
      , nbinsy, fYaxis.GetXmin(), fYaxis.GetXmax());

   //Loop on all cells in X,Y generate a projection along Z
   TH1D *hpz = new TH1D("R_temp","_temp",nbinsz, fZaxis.GetXmin(), fZaxis.GetXmax());
   Int_t bin,binx,biny,binz;
   for (biny=binminy;biny<=binmaxy;biny++) {
      Float_t y = fYaxis.GetBinCenter(biny);
      for (binx=binminx;binx<=binmaxx;binx++) {
         Float_t x = fXaxis.GetBinCenter(binx);
         hpz->Reset();
         Int_t nfill = 0;
         for (binz=1;binz<=nbinsz;binz++) {
            bin = GetBin(binx,biny,binz);
            Float_t w = GetBinContent(bin);
            if (w == 0) continue;
            hpz->Fill(fZaxis.GetBinCenter(binz),w);
            hpz->SetBinError(binz,GetBinError(bin));
            nfill++;
         }
         if (nfill < cut) continue;
         f1->SetParameters(parsave);
         hpz->Fit(fname,option);
         Int_t npfits = f1->GetNumberFitPoints();
         if (npfits > npar && npfits >= cut) {
            for (ipar=0;ipar<npar;ipar++) {
               hlist[ipar]->Fill(x,y,f1->GetParameter(ipar));
               hlist[ipar]->SetCellError(binx,biny,f1->GetParError(ipar));
            }
            hchi2->Fill(x,y,f1->GetChisquare()/(npfits-npar));
         }
      }
   }
   delete [] parsave;
   delete hpz;
}

//______________________________________________________________________________
Double_t TH3::GetBinWithContent3(Double_t c, Int_t &binx, Int_t &biny, Int_t &binz, Int_t firstx, Int_t lastx, Int_t firsty, Int_t lasty, Int_t firstz, Int_t lastz, Double_t maxdiff) const
{
   // compute first cell (binx,biny,binz) in the range [firstx,lastx](firsty,lasty][firstz,lastz] for which
   // diff = abs(cell_content-c) <= maxdiff
   // In case several cells in the specified range with diff=0 are found
   // the first cell found is returned in binx,biny,binz.
   // In case several cells in the specified range satisfy diff <=maxdiff
   // the cell with the smallest difference is returned in binx,biny,binz.
   // In all cases the function returns the smallest difference.
   //
   // NOTE1: if firstx <= 0, firstx is set to bin 1
   //        if (lastx < firstx then firstx is set to the number of bins in X
   //        ie if firstx=0 and lastx=0 (default) the search is on all bins in X.
   //        if firsty <= 0, firsty is set to bin 1
   //        if (lasty < firsty then firsty is set to the number of bins in Y
   //        ie if firsty=0 and lasty=0 (default) the search is on all bins in Y.
   //        if firstz <= 0, firstz is set to bin 1
   //        if (lastz < firstz then firstz is set to the number of bins in Z
   //        ie if firstz=0 and lastz=0 (default) the search is on all bins in Z.
   // NOTE2: if maxdiff=0 (default), the first cell with content=c is returned.

   if (fDimension != 3) {
      binx = 0;
      biny = 0;
      binz = 0;
      Error("GetBinWithContent3","function is only valid for 3-D histograms");
      return 0;
   }
   if (firstx <= 0) firstx = 1;
   if (lastx < firstx) lastx = fXaxis.GetNbins();
   if (firsty <= 0) firsty = 1;
   if (lasty < firsty) lasty = fYaxis.GetNbins();
   if (firstz <= 0) firstz = 1;
   if (lastz < firstz) lastz = fZaxis.GetNbins();
   Int_t binminx = 0, binminy=0, binminz=0;
   Double_t diff, curmax = 1.e240;
   for (Int_t k=firstz;k<=lastz;k++) {
      for (Int_t j=firsty;j<=lasty;j++) {
         for (Int_t i=firstx;i<=lastx;i++) {
            diff = TMath::Abs(GetBinContent(i,j,k)-c);
            if (diff <= 0) {binx = i; biny=j; binz=k; return diff;}
            if (diff < curmax && diff <= maxdiff) {curmax = diff, binminx=i; binminy=j;binminz=k;}
         }
      }
   }
   binx = binminx;
   biny = binminy;
   binz = binminz;
   return curmax;
}

//______________________________________________________________________________
Double_t TH3::GetCorrelationFactor(Int_t axis1, Int_t axis2) const
{
   //*-*-*-*-*-*-*-*Return correlation factor between axis1 and axis2*-*-*-*-*
   //*-*            ====================================================
   if (axis1 < 1 || axis2 < 1 || axis1 > 3 || axis2 > 3) {
      Error("GetCorrelationFactor","Wrong parameters");
      return 0;
   }
   if (axis1 == axis2) return 1;
   Double_t rms1 = GetRMS(axis1);
   if (rms1 == 0) return 0;
   Double_t rms2 = GetRMS(axis2);
   if (rms2 == 0) return 0;
   return GetCovariance(axis1,axis2)/rms1/rms2;
}

//______________________________________________________________________________
Double_t TH3::GetCovariance(Int_t axis1, Int_t axis2) const
{
   //*-*-*-*-*-*-*-*Return covariance between axis1 and axis2*-*-*-*-*
   //*-*            ====================================================

   if (axis1 < 1 || axis2 < 1 || axis1 > 3 || axis2 > 3) {
      Error("GetCovariance","Wrong parameters");
      return 0;
   }
   Double_t stats[11];
   GetStats(stats);
   Double_t sumw   = stats[0];
   Double_t sumw2  = stats[1];
   Double_t sumwx  = stats[2];
   Double_t sumwx2 = stats[3];
   Double_t sumwy  = stats[4];
   Double_t sumwy2 = stats[5];
   Double_t sumwxy = stats[6];
   Double_t sumwz  = stats[7];
   Double_t sumwz2 = stats[8];
   Double_t sumwxz = stats[9];
   Double_t sumwyz = stats[10];

   if (sumw == 0) return 0;
   if (axis1 == 1 && axis2 == 1) {
      return TMath::Abs(sumwx2/sumw - sumwx*sumwx/sumw2);
   }
   if (axis1 == 2 && axis2 == 2) {
      return TMath::Abs(sumwy2/sumw - sumwy*sumwy/sumw2);
   }
   if (axis1 == 3 && axis2 == 3) {
      return TMath::Abs(sumwz2/sumw - sumwz*sumwz/sumw2);
   }
   if ((axis1 == 1 && axis2 == 2) || (axis1 == 2 && axis1 == 1)) {
      return sumwxy/sumw - sumwx/sumw*sumwy/sumw;
   }
   if ((axis1 == 1 && axis2 == 3) || (axis1 == 3 && axis2 == 1)) {
      return sumwxz/sumw - sumwx/sumw*sumwz/sumw;
   }
   if ((axis1 == 2 && axis2 == 3) || (axis1 == 3 && axis2 == 2)) {
      return sumwyz/sumw - sumwy/sumw*sumwz/sumw;
   }
   return 0;
}


//______________________________________________________________________________
void TH3::GetRandom3(Double_t &x, Double_t &y, Double_t &z)
{
   // return 3 random numbers along axis x , y and z distributed according
   // the cellcontents of a 3-dim histogram

   Int_t nbinsx = GetNbinsX();
   Int_t nbinsy = GetNbinsY();
   Int_t nbinsz = GetNbinsZ();
   Int_t nxy    = nbinsx*nbinsy;
   Int_t nbins  = nxy*nbinsz;
   Double_t integral;
   if (fIntegral) {
      if (fIntegral[nbins+1] != fEntries) integral = ComputeIntegral();
   } else {
      integral = ComputeIntegral();
      if (integral == 0 || fIntegral == 0) return;
   }
   Double_t r1 = gRandom->Rndm();
   Int_t ibin = TMath::BinarySearch(nbins,fIntegral,(Double_t) r1);
   Int_t binz = ibin/nxy;
   Int_t biny = (ibin - nxy*binz)/nbinsx;
   Int_t binx = ibin - nbinsx*(biny + nbinsy*binz);
   x = fXaxis.GetBinLowEdge(binx+1);
   if (r1 > fIntegral[ibin]) x +=
      fXaxis.GetBinWidth(binx+1)*(r1-fIntegral[ibin])/(fIntegral[ibin+1] - fIntegral[ibin]);
   y = fYaxis.GetBinLowEdge(biny+1) + fYaxis.GetBinWidth(biny+1)*gRandom->Rndm();
   z = fZaxis.GetBinLowEdge(binz+1) + fZaxis.GetBinWidth(binz+1)*gRandom->Rndm();
}

//______________________________________________________________________________
void TH3::GetStats(Double_t *stats) const
{
   // fill the array stats from the contents of this histogram
   // The array stats must be correctly dimensionned in the calling program.
   // stats[0] = sumw
   // stats[1] = sumw2
   // stats[2] = sumwx
   // stats[3] = sumwx2
   // stats[4] = sumwy
   // stats[5] = sumwy2
   // stats[6] = sumwxy
   // stats[7] = sumwz
   // stats[8] = sumwz2
   // stats[9] = sumwxz
   // stats[10]= sumwyz

   if (fBuffer) ((TH3*)this)->BufferEmpty();

   Int_t bin, binx, biny, binz;
   Double_t w,err;
   Double_t x,y,z;
   if (fTsumw == 0 || fXaxis.TestBit(TAxis::kAxisRange) || fYaxis.TestBit(TAxis::kAxisRange) || fZaxis.TestBit(TAxis::kAxisRange)) {
      for (bin=0;bin<9;bin++) stats[bin] = 0;

      Int_t firstBinX = fXaxis.GetFirst();
      Int_t lastBinX  = fXaxis.GetLast();
      Int_t firstBinY = fYaxis.GetFirst();
      Int_t lastBinY  = fYaxis.GetLast();
      Int_t firstBinZ = fZaxis.GetFirst();
      Int_t lastBinZ  = fZaxis.GetLast();
      // include underflow/overflow if TH1::StatOverflows(kTRUE) in case no range is set on the axis
      if (fgStatOverflows) {
         if ( !fXaxis.TestBit(TAxis::kAxisRange) ) {
            if (firstBinX == 1) firstBinX = 0;
            if (lastBinX ==  fXaxis.GetNbins() ) lastBinX += 1;
         }
         if ( !fYaxis.TestBit(TAxis::kAxisRange) ) {
            if (firstBinY == 1) firstBinY = 0;
            if (lastBinY ==  fYaxis.GetNbins() ) lastBinY += 1;
         }
         if ( !fZaxis.TestBit(TAxis::kAxisRange) ) {
            if (firstBinZ == 1) firstBinZ = 0;
            if (lastBinZ ==  fZaxis.GetNbins() ) lastBinZ += 1;
         }
      }
      for (binz = firstBinZ; binz <= lastBinZ; binz++) {
         z = fZaxis.GetBinCenter(binz);
         for (biny = firstBinY; biny <= lastBinY; biny++) {
            y = fYaxis.GetBinCenter(biny);
            for (binx = firstBinX; binx <= lastBinX; binx++) {
               bin = GetBin(binx,biny,binz);
               x   = fXaxis.GetBinCenter(binx);
               w   = TMath::Abs(GetBinContent(bin));
               err = TMath::Abs(GetBinError(bin));
               stats[0] += w;
               stats[1] += err*err;
               stats[2] += w*x;
               stats[3] += w*x*x;
               stats[4] += w*y;
               stats[5] += w*y*y;
               stats[6] += w*x*y;
               stats[7] += w*z;
               stats[8] += w*z*z;
               stats[9] += w*x*z;
               stats[10]+= w*y*z;
            }
         }
      }
   } else {
      stats[0] = fTsumw;
      stats[1] = fTsumw2;
      stats[2] = fTsumwx;
      stats[3] = fTsumwx2;
      stats[4] = fTsumwy;
      stats[5] = fTsumwy2;
      stats[6] = fTsumwxy;
      stats[7] = fTsumwz;
      stats[8] = fTsumwz2;
      stats[9] = fTsumwxz;
      stats[10]= fTsumwyz;
   }
}

//______________________________________________________________________________
Double_t TH3::Integral(Option_t *option) const
{
   //Return integral of bin contents. Only bins in the bins range are considered.
   // By default the integral is computed as the sum of bin contents in the range.
   // if option "width" is specified, the integral is the sum of
   // the bin contents multiplied by the bin width in x, y and in z.

   return Integral(fXaxis.GetFirst(),fXaxis.GetLast(),
      fYaxis.GetFirst(),fYaxis.GetLast(),
      fZaxis.GetFirst(),fZaxis.GetLast(),option);
}

//______________________________________________________________________________
Double_t TH3::Integral(Int_t binx1, Int_t binx2, Int_t biny1, Int_t biny2, Int_t binz1, Int_t binz2, Option_t *option) const
{
   //Return integral of bin contents in range [binx1,binx2],[biny1,biny2],[binz1,binz2]
   // for a 3-D histogram
   // By default the integral is computed as the sum of bin contents in the range.
   // if option "width" is specified, the integral is the sum of
   // the bin contents multiplied by the bin width in x, y and in z.

   Int_t nbinsx = GetNbinsX();
   Int_t nbinsy = GetNbinsY();
   Int_t nbinsz = GetNbinsZ();
   if (binx1 < 0) binx1 = 0;
   if (binx2 > nbinsx+1) binx2 = nbinsx+1;
   if (binx2 < binx1)    binx2 = nbinsx;
   if (biny1 < 0) biny1 = 0;
   if (biny2 > nbinsy+1) biny2 = nbinsy+1;
   if (biny2 < biny1)    biny2 = nbinsy;
   if (binz1 < 0) binz1 = 0;
   if (binz2 > nbinsz+1) binz2 = nbinsz+1;
   if (binz2 < binz1)    binz2 = nbinsz;
   Double_t integral = 0;

   //*-*- Loop on bins in specified range
   TString opt = option;
   opt.ToLower();
   Bool_t width = kFALSE;
   if (opt.Contains("width")) width = kTRUE;
   Int_t bin, binx, biny, binz;
   for (binz=binz1;binz<=binz2;binz++) {
      for (biny=biny1;biny<=biny2;biny++) {
         for (binx=binx1;binx<=binx2;binx++) {
            bin = binx +(nbinsx+2)*(biny + (nbinsy+2)*binz);
            if (width) integral += GetBinContent(bin)*fXaxis.GetBinWidth(binx)*fYaxis.GetBinWidth(biny)*fZaxis.GetBinWidth(binz);
            else       integral += GetBinContent(bin);
         }
      }
   }
   return integral;
}

//______________________________________________________________________________
Double_t TH3::Interpolate(Double_t)
{
   
   //Not yet implemented
   Error("Interpolate","This function must be called with 3 arguments for a TH3");
   return 0;
}

//______________________________________________________________________________
Double_t TH3::Interpolate(Double_t, Double_t)
{
   
   //Not yet implemented
   Error("Interpolate","This function must be called with 3 arguments for a TH3");
   return 0;
}

//______________________________________________________________________________
Double_t TH3::Interpolate(Double_t, Double_t, Double_t)
{
   
   //Not yet implemented
   Error("Interpolate","This function is not yet implemented for a TH3");
   return 0;
}

//______________________________________________________________________________
Double_t TH3::KolmogorovTest(const TH1 *h2, Option_t *option) const
{
   //  Statistical test of compatibility in shape between
   //  THIS histogram and h2, using Kolmogorov test.
   //     Default: Ignore under- and overflow bins in comparison
   //
   //     option is a character string to specify options
   //         "U" include Underflows in test
   //         "O" include Overflows
   //         "N" include comparison of normalizations
   //         "D" Put out a line of "Debug" printout
   //         "M" Return the Maximum Kolmogorov distance instead of prob
   //
   //   The returned function value is the probability of test
   //       (much less than one means NOT compatible)
   //
   //   The KS test uses the distance between the pseudo-CDF's obtained 
   //   from the histogram. Since in more than 1D the order for generating the pseudo-CDF is 
   //   arbitrary, we use the pseudo-CDF's obtained from all the possible 6 combinatons of the 3 axis. 
   //   The average of all the maximum  distances obtained is used in the tests.  

   TString opt = option;
   opt.ToUpper();

   Double_t prb = 0;
   TH1 *h1 = (TH1*)this;
   if (h2 == 0) return 0;
   TAxis *xaxis1 = h1->GetXaxis();
   TAxis *xaxis2 = h2->GetXaxis();
   TAxis *yaxis1 = h1->GetYaxis();
   TAxis *yaxis2 = h2->GetYaxis();
   TAxis *zaxis1 = h1->GetZaxis();
   TAxis *zaxis2 = h2->GetZaxis();
   Int_t ncx1   = xaxis1->GetNbins();
   Int_t ncx2   = xaxis2->GetNbins();
   Int_t ncy1   = yaxis1->GetNbins();
   Int_t ncy2   = yaxis2->GetNbins();
   Int_t ncz1   = zaxis1->GetNbins();
   Int_t ncz2   = zaxis2->GetNbins();

   // Check consistency of dimensions
   if (h1->GetDimension() != 3 || h2->GetDimension() != 3) {
      Error("KolmogorovTest","Histograms must be 3-D\n");
      return 0;
   }

   // Check consistency in number of channels
   if (ncx1 != ncx2) {
      Error("KolmogorovTest","Number of channels in X is different, %d and %d\n",ncx1,ncx2);
      return 0;
   }
   if (ncy1 != ncy2) {
      Error("KolmogorovTest","Number of channels in Y is different, %d and %d\n",ncy1,ncy2);
      return 0;
   }
   if (ncz1 != ncz2) {
      Error("KolmogorovTest","Number of channels in Z is different, %d and %d\n",ncz1,ncz2);
      return 0;
   }

   // Check consistency in channel edges
   Bool_t afunc1 = kFALSE;
   Bool_t afunc2 = kFALSE;
   Double_t difprec = 1e-5;
   Double_t diff1 = TMath::Abs(xaxis1->GetXmin() - xaxis2->GetXmin());
   Double_t diff2 = TMath::Abs(xaxis1->GetXmax() - xaxis2->GetXmax());
   if (diff1 > difprec || diff2 > difprec) {
      Error("KolmogorovTest","histograms with different binning along X");
      return 0;
   }
   diff1 = TMath::Abs(yaxis1->GetXmin() - yaxis2->GetXmin());
   diff2 = TMath::Abs(yaxis1->GetXmax() - yaxis2->GetXmax());
   if (diff1 > difprec || diff2 > difprec) {
      Error("KolmogorovTest","histograms with different binning along Y");
      return 0;
   }
   diff1 = TMath::Abs(zaxis1->GetXmin() - zaxis2->GetXmin());
   diff2 = TMath::Abs(zaxis1->GetXmax() - zaxis2->GetXmax());
   if (diff1 > difprec || diff2 > difprec) {
      Error("KolmogorovTest","histograms with different binning along Z");
      return 0;
   }

   //   Should we include Uflows, Oflows?
   Int_t ibeg = 1, jbeg = 1, kbeg = 1;
   Int_t iend = ncx1, jend = ncy1, kend = ncz1;
   if (opt.Contains("U")) {ibeg = 0; jbeg = 0; kbeg = 0;}
   if (opt.Contains("O")) {iend = ncx1+1; jend = ncy1+1; kend = ncz1+1;}

   Int_t i,j,k,bin;
   Double_t sum1  = 0;
   Double_t sum2  = 0;
   Double_t w1    = 0;
   Double_t w2    = 0;
   for (i = ibeg; i <= iend; i++) {
      for (j = jbeg; j <= jend; j++) {
         for (k = kbeg; k <= kend; k++) {
            bin = h1->GetBin(i,j,k);
            sum1 += h1->GetBinContent(bin);
            sum2 += h1->GetBinContent(bin);
            Double_t ew1   = h1->GetBinError(bin);
            Double_t ew2   = h2->GetBinError(bin);
            w1   += ew1*ew1;
            w2   += ew2*ew2;
         }
      }
   }


   //    Check that both scatterplots contain events
   if (sum1 == 0) {
      Error("KolmogorovTest","Integral is zero for h1=%s\n",h1->GetName());
      return 0;
   }
   if (sum2 == 0) {
      Error("KolmogorovTest","Integral is zero for h2=%s\n",h2->GetName());
      return 0;
   }
   // calculate the effective entries.  
   // the case when errors are zero (w1 == 0 or w2 ==0) are equivalent to 
   // compare to a function. In that case the rescaling is done only on sqrt(esum2) or sqrt(esum1) 
   Double_t esum1 = 0, esum2 = 0; 
   if (w1 > 0) 
      esum1 = sum1 * sum1 / w1; 
   else 
      afunc1 = kTRUE;    // use later for calculating z
   
   if (w2 > 0) 
      esum2 = sum2 * sum2 / w2; 
   else 
      afunc2 = kTRUE;    // use later for calculating z
   
   if (afunc2 && afunc1) { 
      Error("KolmogorovTest","Errors are zero for both histograms\n");
      return 0;
   }

   //   Find Kolmogorov distance
   //   order is arbitrary take average of all possible 6 starting orders x,y,z 
   int order[3] = {0,1,2};
   int binbeg[3]; 
   int binend[3]; 
   int ibin[3];
   binbeg[0] = ibeg; binbeg[1] = jbeg; binbeg[2] = kbeg; 
   binend[0] = iend; binend[1] = jend; binend[2] = kend; 
   Double_t vdfmax[6]; // there are in total 6 combinations 
   int icomb = 0; 
   Double_t s1 = 1/sum1;
   Double_t s2 = 1/sum2;
   Double_t rsum1=0, rsum2=0;
   do { 
      // loop on bins
      Double_t dmax = 0;
      for (i = binbeg[order[0] ]; i <= binend[order[0] ]; i++) {
         for ( j = binbeg[order[1] ]; j <= binend[order[1] ]; j++) {
            for ( k = binbeg[order[2] ]; k <= binend[order[2] ]; k++) {
                  ibin[ order[0] ] = i;
                  ibin[ order[1] ] = j;
                  ibin[ order[2] ] = k;
                  bin = h1->GetBin(ibin[0],ibin[1],ibin[2]);
                  rsum1 += s1*h1->GetBinContent(bin);
                  rsum2 += s2*h2->GetBinContent(bin);
                  dmax   = TMath::Max(dmax, TMath::Abs(rsum1-rsum2));
            }
         }
      }
      vdfmax[icomb] = dmax; 
      icomb++;
   } while (TMath::Permute(3,order)  );


   // get average of distances 
   Double_t dfmax = TMath::Mean(6,vdfmax);
   
   //    Get Kolmogorov probability
   Double_t factnm;
   if (afunc1)      factnm = TMath::Sqrt(sum2);
   else if (afunc2) factnm = TMath::Sqrt(sum1);
   else             factnm = TMath::Sqrt(sum1*sum2/(sum1+sum2));
   Double_t z  = dfmax*factnm;

   prb = TMath::KolmogorovProb(z); 

   Double_t prb1 = 0, prb2 = 0; 
   // option N to combine normalization makes sense if both afunc1 and afunc2 are false
   if (opt.Contains("N")  && !(afunc1 || afunc2 ) ) { 
      // Combine probabilities for shape and normalization
      prb1   = prb;
      Double_t d12    = esum1-esum2;
      Double_t chi2   = d12*d12/(esum1+esum2);
      prb2   = TMath::Prob(chi2,1);
      //     see Eadie et al., section 11.6.2
      if (prb > 0 && prb2 > 0) prb = prb*prb2*(1-TMath::Log(prb*prb2));
      else                     prb = 0;
   }

   //    debug printout
   if (opt.Contains("D")) {
      printf(" Kolmo Prob  h1 = %s, sum1=%g\n",h1->GetName(),sum1);
      printf(" Kolmo Prob  h2 = %s, sum2=%g\n",h2->GetName(),sum2);
      printf(" Kolmo Probabil = %f, Max Dist = %g\n",prb,dfmax);
      if (opt.Contains("N"))
         printf(" Kolmo Probabil = %f for shape alone, =%f for normalisation alone\n",prb1,prb2);
   }
   // This numerical error condition should never occur:
   if (TMath::Abs(rsum1-1) > 0.002) Warning("KolmogorovTest","Numerical problems with h1=%s\n",h1->GetName());
   if (TMath::Abs(rsum2-1) > 0.002) Warning("KolmogorovTest","Numerical problems with h2=%s\n",h2->GetName());

   if(opt.Contains("M"))      return dfmax;  // return avergae of max distance

   return prb;
}


//______________________________________________________________________________
Long64_t TH3::Merge(TCollection *list)
{
   //Add all histograms in the collection to this histogram.
   //This function computes the min/max for the axes,
   //compute a new number of bins, if necessary,
   //add bin contents, errors and statistics.
   //If overflows are present and limits are different the function will fail.
   //The function returns the total number of entries in the result histogram
   //if the merge is successfull, -1 otherwise.
   //
   //IMPORTANT remark. The 2 axis x and y may have different number
   //of bins and different limits, BUT the largest bin width must be
   //a multiple of the smallest bin width and the upper limit must also
   //be a multiple of the bin width.

   if (!list) return 0;
   if (list->IsEmpty()) return (Int_t) GetEntries();

   TList inlist;
   TH1* hclone = (TH1*)Clone("FirstClone");
   R__ASSERT(hclone);
   BufferEmpty(1);         // To remove buffer.
   Reset();                // BufferEmpty sets limits so we can't use it later.
   SetEntries(0);
   inlist.Add(hclone);
   inlist.AddAll(list);

   TAxis newXAxis;
   TAxis newYAxis;
   TAxis newZAxis;
   Bool_t initialLimitsFound = kFALSE;
   Bool_t same = kTRUE;
   Bool_t allHaveLimits = kTRUE;

   TIter next(&inlist);
   while (TObject *o = next()) {
      TH3* h = dynamic_cast<TH3*> (o);
      if (!h) {
         Error("Add","Attempt to add object of class: %s to a %s",
            o->ClassName(),this->ClassName());
         return -1;
      }
      Bool_t hasLimits = h->GetXaxis()->GetXmin() < h->GetXaxis()->GetXmax();
      allHaveLimits = allHaveLimits && hasLimits;

      if (hasLimits) {
         h->BufferEmpty();
         if (!initialLimitsFound) {
            initialLimitsFound = kTRUE;
            newXAxis.Set(h->GetXaxis()->GetNbins(), h->GetXaxis()->GetXmin(),
               h->GetXaxis()->GetXmax());
            newYAxis.Set(h->GetYaxis()->GetNbins(), h->GetYaxis()->GetXmin(),
               h->GetYaxis()->GetXmax());
            newZAxis.Set(h->GetZaxis()->GetNbins(), h->GetZaxis()->GetXmin(),
               h->GetZaxis()->GetXmax());
         }
         else {
            if (!RecomputeAxisLimits(newXAxis, *(h->GetXaxis()))) {
               Error("Merge", "Cannot merge histograms - limits are inconsistent:\n "
                  "first: (%d, %f, %f), second: (%d, %f, %f)",
                  newXAxis.GetNbins(), newXAxis.GetXmin(), newXAxis.GetXmax(),
                  h->GetXaxis()->GetNbins(), h->GetXaxis()->GetXmin(),
                  h->GetXaxis()->GetXmax());
            }
            if (!RecomputeAxisLimits(newYAxis, *(h->GetYaxis()))) {
               Error("Merge", "Cannot merge histograms - limits are inconsistent:\n "
                  "first: (%d, %f, %f), second: (%d, %f, %f)",
                  newYAxis.GetNbins(), newYAxis.GetXmin(), newYAxis.GetXmax(),
                  h->GetYaxis()->GetNbins(), h->GetYaxis()->GetXmin(),
                  h->GetYaxis()->GetXmax());
            }
            if (!RecomputeAxisLimits(newZAxis, *(h->GetZaxis()))) {
               Error("Merge", "Cannot merge histograms - limits are inconsistent:\n "
                  "first: (%d, %f, %f), second: (%d, %f, %f)",
                  newZAxis.GetNbins(), newZAxis.GetXmin(), newZAxis.GetXmax(),
                  h->GetZaxis()->GetNbins(), h->GetZaxis()->GetXmin(),
                  h->GetZaxis()->GetXmax());
            }
         }
      }
   }
   next.Reset();

   same = same && SameLimitsAndNBins(newXAxis, *GetXaxis())
      && SameLimitsAndNBins(newYAxis, *GetYaxis());
   if (!same && initialLimitsFound)
      SetBins(newXAxis.GetNbins(), newXAxis.GetXmin(), newXAxis.GetXmax(),
      newYAxis.GetNbins(), newYAxis.GetXmin(), newYAxis.GetXmax(),
      newZAxis.GetNbins(), newZAxis.GetXmin(), newZAxis.GetXmax());

   if (!allHaveLimits) {
      // fill this histogram with all the data from buffers of histograms without limits
      while (TH3* h = dynamic_cast<TH3*> (next())) {
         if (h->GetXaxis()->GetXmin() >= h->GetXaxis()->GetXmax() && h->fBuffer) {
            // no limits
            Int_t nbentries = (Int_t)h->fBuffer[0];
            for (Int_t i = 0; i < nbentries; i++)
               Fill(h->fBuffer[4*i + 2], h->fBuffer[4*i + 3],
               h->fBuffer[4*i + 4], h->fBuffer[4*i + 1]);
            // Entries from buffers have to be filled one by one
            // because FillN doesn't resize histograms.
         }
      }
      if (!initialLimitsFound)
         return (Int_t) GetEntries();  // all histograms have been processed
      next.Reset();
   }

   //merge bin contents and errors
   Double_t stats[kNstat], totstats[kNstat];
   for (Int_t i=0;i<kNstat;i++) {totstats[i] = stats[i] = 0;}
   GetStats(totstats);
   Double_t nentries = GetEntries();
   Int_t binx, biny, binz, ix, iy, iz, nx, ny, nz, bin, ibin;
   Double_t cu;
   Int_t nbix = fXaxis.GetNbins();
   Int_t nbiy = fYaxis.GetNbins();
   Bool_t canRebin=TestBit(kCanRebin);
   ResetBit(kCanRebin); // reset, otherwise setting the under/overflow will rebin

   while (TH1* h=(TH1*)next()) {
      // process only if the histogram has limits; otherwise it was processed before
      if (h->GetXaxis()->GetXmin() < h->GetXaxis()->GetXmax()) {
         // import statistics
         h->GetStats(stats);
         for (Int_t i = 0; i < kNstat; i++)
            totstats[i] += stats[i];
         nentries += h->GetEntries();

         nx = h->GetXaxis()->GetNbins();
         ny = h->GetYaxis()->GetNbins();
         nz = h->GetZaxis()->GetNbins();

         for (binz = 0; binz <= nz + 1; binz++) {
            iz = fZaxis.FindBin(h->GetZaxis()->GetBinCenter(binz));
            for (biny = 0; biny <= ny + 1; biny++) {
               iy = fYaxis.FindBin(h->GetYaxis()->GetBinCenter(biny));
               for (binx = 0; binx <= nx + 1; binx++) {
                  ix = fXaxis.FindBin(h->GetXaxis()->GetBinCenter(binx));
                  bin = binx +(nx+2)*(biny + (ny+2)*binz);
                  ibin = ix +(nbix+2)*(iy + (nbiy+2)*iz);
                  cu  = h->GetBinContent(bin);
                  if ((!same) && (binx == 0 || binx == nx + 1
                     || biny == 0 || biny == ny + 1
                     || binz == 0 || binz == nz + 1)) {
                        if (cu != 0) {
                           Error("Merge", "Cannot merge histograms - the histograms have"
                              " different limits and undeflows/overflows are present."
                              " The initial histogram is now broken!");
                           return -1;
                        }
                  }
                  AddBinContent(ibin,cu);
                  if (fSumw2.fN) {
                     Double_t error1 = h->GetBinError(bin);
                     fSumw2.fArray[ibin] += error1*error1;
                  }
               }
            }
         }
      }
   }
   if (canRebin) SetBit(kCanRebin);

   //copy merged stats
   PutStats(totstats);
   SetEntries(nentries);
   inlist.Remove(hclone);
   delete hclone;
   return (Long64_t)nentries;
}

//______________________________________________________________________________
TH1D *TH3::ProjectionZ(const char *name, Int_t ixmin, Int_t ixmax, Int_t iymin, Int_t iymax, Option_t *option) const
{
   //*-*-*-*-*Project a 3-D histogram into a 1-D histogram along Z*-*-*-*-*-*-*
   //*-*      ====================================================
   //
   //   The projection is always of the type TH1D.
   //   The projection is made from the cells along the X axis
   //   ranging from ixmin to ixmax and iymin to iymax included.
   //   By default, bins 1 to nx and 1 to ny  are included
   //
   //   if option "e" is specified, the errors are computed.
   //   if option "d" is specified, the projection is drawn in the current pad.
   //
   //  implemented using Project3D


   TString opt = option;
   opt.ToLower();

   GetXaxis()->SetRange(ixmin,ixmax);
   GetYaxis()->SetRange(iymin,iymax);
   opt.Append("z");
   TH1D * h1 = (TH1D* ) Project3D(opt.Data());

   // rename the histogram to the given name
   char *pname = (char*)name;
   if (strcmp(name,"_pz") == 0) {
      Int_t nch = strlen(GetName()) + 4;
      pname = new char[nch];
      sprintf(pname,"%s%s",GetName(),name);
   }
   h1->SetName(pname);

   if (pname != name) delete [] pname;

   GetXaxis()->SetRange(0,0);
   GetYaxis()->SetRange(0,0);

   if (opt.Contains("d")) {
      TVirtualPad *padsav = gPad;
      TVirtualPad *pad = gROOT->GetSelectedPad();
      if (pad) pad->cd();
      char optin[100];
      strcpy(optin,opt.Data());
      char *d = (char*)strstr(optin,"d"); if (d) {*d = ' '; if (*(d+1) == 0) *d=0;}
      char *e = (char*)strstr(optin,"e"); if (e) {*e = ' '; if (*(e+1) == 0) *e=0;}
      if (!gPad->FindObject(h1)) {
         h1->Draw(optin);
      } else {
         h1->Paint(optin);
      }
      if (padsav) padsav->cd();
   }

   return h1;
}

//______________________________________________________________________________
TH1 *TH3::Project3D(Option_t *option) const
{
   // Project a 3-d histogram into 1 or 2-d histograms depending on the
   // option parameter
   // option may contain a combination of the characters x,y,z,e
   // option = "x" return the x projection into a TH1D histogram
   // option = "y" return the y projection into a TH1D histogram
   // option = "z" return the z projection into a TH1D histogram
   // option = "xy" return the x versus y projection into a TH2D histogram
   // option = "yx" return the y versus x projection into a TH2D histogram
   // option = "xz" return the x versus z projection into a TH2D histogram
   // option = "zx" return the z versus x projection into a TH2D histogram
   // option = "yz" return the y versus z projection into a TH2D histogram
   // option = "zy" return the z versus y projection into a TH2D histogram
   //
   // If option contains the string "e", errors are computed
   //
   // The projection is made for the selected bins only.
   // To select a bin range along an axis, use TAxis::SetRange, eg
   //    h3.GetYaxis()->SetRange(23,56);
   //
   // NOTE 1: The generated histogram is named th3name + option
   // eg if the TH3* h histogram is named "myhist", then
   // h->Project3D("xy"); produces a TH2D histogram named "myhist_xy"
   // if a histogram of the same type already exists, it is overwritten.
   // The following sequence
   //    h->Project3D("xy");
   //    h->Project3D("xy2");
   //  will generate two TH2D histograms named "myhist_xy" and "myhist_xy2"
   //
   //  NOTE 2: The number of entries in the projected histogram is estimated from the number of 
   //  effective entries for all the cells included in the projection. 
   //
   //  NOTE 3: underflow/overflow are included by default in the projection 
   //  To exclude underflow and/or overflow (for both axis in case of a projection to a 1D histogram) use option "NUF" and/or "NOF"
   //  With SetRange() you can have all bin except underflow/overflow only if you set the axis bit range as 
   // following after having called SetRange: 
   //    axis->SetRange(1, axis->GetNbins());
   //    axis->SetBit(TAxis::kAxisRange);  
   //          

   TString opt = option; opt.ToLower();
   Int_t ixmin = fXaxis.GetFirst();
   Int_t ixmax = fXaxis.GetLast();
   Int_t iymin = fYaxis.GetFirst();
   Int_t iymax = fYaxis.GetLast();
   Int_t izmin = fZaxis.GetFirst();
   Int_t izmax = fZaxis.GetLast();
   Int_t nx = ixmax-ixmin+1;
   Int_t ny = iymax-iymin+1;
   Int_t nz = izmax-izmin+1;
   Int_t pcase = 0;
   if (opt.Contains("x"))  pcase = 1;
   if (opt.Contains("y"))  pcase = 2;
   if (opt.Contains("z"))  pcase = 3;
   if (opt.Contains("xy")) pcase = 4;
   if (opt.Contains("yx")) pcase = 5;
   if (opt.Contains("xz")) pcase = 6;
   if (opt.Contains("zx")) pcase = 7;
   if (opt.Contains("yz")) pcase = 8;
   if (opt.Contains("zy")) pcase = 9;

   // Create the projection histogram
   TH1D *h1 = 0;
   TH2D *h2 = 0;
   Int_t nch = strlen(GetName()) +opt.Length() +2;
   char *name = new char[nch];
   sprintf(name,"%s_%s",GetName(),option);
   nch = strlen(GetTitle()) +opt.Length() +2;
   char *title = new char[nch];
   sprintf(title,"%s_%s",GetTitle(),option);
   TObject *h1obj = gROOT->FindObject(name);
   if (h1obj && !h1obj->InheritsFrom("TH1")) h1obj = 0;
   const TArrayD *bins;
   const TArrayD *xbins;
   const TArrayD *ybins;
   const TArrayD *zbins;
   switch (pcase) {
      case 1:
         // "x"
         if (h1obj && h1obj->InheritsFrom("TH1D")) {
            h1 = (TH1D*)h1obj;
            h1->Reset();
            break;
         }
         bins = fXaxis.GetXbins();
         if (bins->fN == 0) {
            h1 = new TH1D(name,title,nx,fXaxis.GetBinLowEdge(ixmin),fXaxis.GetBinUpEdge(ixmax));
         } else {
            h1 = new TH1D(name,title,nx,&bins->fArray[ixmin-1]);
         }
         break;

      case 2:
         // "y"
         if (h1obj && h1obj->InheritsFrom("TH1D")) {
            h1 = (TH1D*)h1obj;
            h1->Reset();
            break;
         }
         bins = fYaxis.GetXbins();
         if (bins->fN == 0) {
            h1 = new TH1D(name,title,ny,fYaxis.GetBinLowEdge(iymin),fYaxis.GetBinUpEdge(iymax));
         } else {
            h1 = new TH1D(name,title,ny,&bins->fArray[iymin-1]);
         }
         break;

      case 3:
         // "z"
         if (h1obj && h1obj->InheritsFrom("TH1D")) {
            h1 = (TH1D*)h1obj;
            h1->Reset();
            break;
         }
         bins = fZaxis.GetXbins();
         if (bins->fN == 0) {
            h1 = new TH1D(name,title,nz,fZaxis.GetBinLowEdge(izmin),fZaxis.GetBinUpEdge(izmax));
         } else {
            h1 = new TH1D(name,title,nz,&bins->fArray[izmin-1]);
         }
         break;
      case 4:
         // "xy"
         if (h1obj && h1obj->InheritsFrom("TH2D")) {
            h2 = (TH2D*)h1obj;
            h2->Reset();
            break;
         }
         xbins = fXaxis.GetXbins();
         ybins = fYaxis.GetXbins();
         if (xbins->fN == 0 && ybins->fN == 0) {
            h2 = new TH2D(name,title,ny,fYaxis.GetBinLowEdge(iymin),fYaxis.GetBinUpEdge(iymax)
               ,nx,fXaxis.GetBinLowEdge(ixmin),fXaxis.GetBinUpEdge(ixmax));
         } else if (ybins->fN == 0) {
            h2 = new TH2D(name,title,ny,fYaxis.GetBinLowEdge(iymin),fYaxis.GetBinUpEdge(iymax)
               ,nx,&xbins->fArray[ixmin-1]);
         } else if (xbins->fN == 0) {
            h2 = new TH2D(name,title,ny,&ybins->fArray[iymin-1]
            ,nx,fXaxis.GetBinLowEdge(ixmin),fXaxis.GetBinUpEdge(ixmax));
         } else {
            h2 = new TH2D(name,title,ny,&ybins->fArray[iymin-1],nx,&xbins->fArray[ixmin-1]);
         }
         break;

      case 5:
         // "yx"
         if (h1obj && h1obj->InheritsFrom("TH2D")) {
            h2 = (TH2D*)h1obj;
            h2->Reset();
            break;
         }
         xbins = fXaxis.GetXbins();
         ybins = fYaxis.GetXbins();
         if (xbins->fN == 0 && ybins->fN == 0) {
            h2 = new TH2D(name,title,nx,fXaxis.GetBinLowEdge(ixmin),fXaxis.GetBinUpEdge(ixmax)
               ,ny,fYaxis.GetBinLowEdge(iymin),fYaxis.GetBinUpEdge(iymax));
         } else if (xbins->fN == 0) {
            h2 = new TH2D(name,title,nx,fXaxis.GetBinLowEdge(ixmin),fXaxis.GetBinUpEdge(ixmax)
               ,ny,&ybins->fArray[iymin-1]);
         } else if (ybins->fN == 0) {
            h2 = new TH2D(name,title,nx,&xbins->fArray[ixmin-1]
            ,ny,fYaxis.GetBinLowEdge(iymin),fYaxis.GetBinUpEdge(iymax));
         } else {
            h2 = new TH2D(name,title,nx,&xbins->fArray[ixmin-1],ny,&ybins->fArray[iymin-1]);
         }
         break;

      case 6:
         // "xz"
         if (h1obj && h1obj->InheritsFrom("TH2D")) {
            h2 = (TH2D*)h1obj;
            h2->Reset();
            break;
         }
         xbins = fXaxis.GetXbins();
         zbins = fZaxis.GetXbins();
         if (xbins->fN == 0 && zbins->fN == 0) {
            h2 = new TH2D(name,title,nz,fZaxis.GetBinLowEdge(izmin),fZaxis.GetBinUpEdge(izmax)
               ,nx,fXaxis.GetBinLowEdge(ixmin),fXaxis.GetBinUpEdge(ixmax));
         } else if (zbins->fN == 0) {
            h2 = new TH2D(name,title,nz,fZaxis.GetBinLowEdge(izmin),fZaxis.GetBinUpEdge(izmax)
               ,nx,&xbins->fArray[ixmin-1]);
         } else if (xbins->fN == 0) {
            h2 = new TH2D(name,title,nz,&zbins->fArray[izmin-1]
            ,nx,fXaxis.GetBinLowEdge(ixmin),fXaxis.GetBinUpEdge(ixmax));
         } else {
            h2 = new TH2D(name,title,nz,&zbins->fArray[izmin-1],nx,&xbins->fArray[ixmin-1]);
         }
         break;

      case 7:
         // "zx"
         if (h1obj && h1obj->InheritsFrom("TH2D")) {
            h2 = (TH2D*)h1obj;
            h2->Reset();
            break;
         }
         xbins = fXaxis.GetXbins();
         zbins = fZaxis.GetXbins();
         if (xbins->fN == 0 && zbins->fN == 0) {
            h2 = new TH2D(name,title,nx,fXaxis.GetBinLowEdge(ixmin),fXaxis.GetBinUpEdge(ixmax)
               ,nz,fZaxis.GetBinLowEdge(izmin),fZaxis.GetBinUpEdge(izmax));
         } else if (xbins->fN == 0) {
            h2 = new TH2D(name,title,nx,fXaxis.GetBinLowEdge(ixmin),fXaxis.GetBinUpEdge(ixmax)
               ,nz,&zbins->fArray[izmin-1]);
         } else if (zbins->fN == 0) {
            h2 = new TH2D(name,title,nx,&xbins->fArray[ixmin-1]
            ,nz,fZaxis.GetBinLowEdge(izmin),fZaxis.GetBinUpEdge(izmax));
         } else {
            h2 = new TH2D(name,title,nx,&xbins->fArray[ixmin-1],nz,&zbins->fArray[izmin-1]);
         }
         break;

      case 8:
         // "yz"
         if (h1obj && h1obj->InheritsFrom("TH2D")) {
            h2 = (TH2D*)h1obj;
            h2->Reset();
            break;
         }
         ybins = fYaxis.GetXbins();
         zbins = fZaxis.GetXbins();
         if (ybins->fN == 0 && zbins->fN == 0) {
            h2 = new TH2D(name,title,nz,fZaxis.GetBinLowEdge(izmin),fZaxis.GetBinUpEdge(izmax)
               ,ny,fYaxis.GetBinLowEdge(iymin),fYaxis.GetBinUpEdge(iymax));
         } else if (zbins->fN == 0) {
            h2 = new TH2D(name,title,nz,fZaxis.GetBinLowEdge(izmin),fZaxis.GetBinUpEdge(izmax)
               ,ny,&ybins->fArray[iymin-1]);
         } else if (ybins->fN == 0) {
            h2 = new TH2D(name,title,nz,&zbins->fArray[izmin-1]
            ,ny,fYaxis.GetBinLowEdge(iymin),fYaxis.GetBinUpEdge(iymax));
         } else {
            h2 = new TH2D(name,title,nz,&zbins->fArray[izmin-1],ny,&ybins->fArray[iymin-1]);
         }
         break;

      case 9:
         // "zy"
         if (h1obj && h1obj->InheritsFrom("TH2D")) {
            h2 = (TH2D*)h1obj;
            h2->Reset();
            break;
         }
         ybins = fYaxis.GetXbins();
         zbins = fZaxis.GetXbins();
         if (ybins->fN == 0 && zbins->fN == 0) {
            h2 = new TH2D(name,title,ny,fYaxis.GetBinLowEdge(iymin),fYaxis.GetBinUpEdge(iymax)
               ,nz,fZaxis.GetBinLowEdge(izmin),fZaxis.GetBinUpEdge(izmax));
         } else if (ybins->fN == 0) {
            h2 = new TH2D(name,title,ny,fYaxis.GetBinLowEdge(iymin),fYaxis.GetBinUpEdge(iymax)
               ,nz,&zbins->fArray[izmin-1]);
         } else if (zbins->fN == 0) {
            h2 = new TH2D(name,title,ny,&ybins->fArray[iymin-1]
            ,nz,fZaxis.GetBinLowEdge(izmin),fZaxis.GetBinUpEdge(izmax));
         } else {
            h2 = new TH2D(name,title,ny,&ybins->fArray[iymin-1],nz,&zbins->fArray[izmin-1]);
         }
         break;

   }

   // Copy the axis attributes and the axis labels if needed.
   if (pcase >=1 && pcase <=3) {
      THashList* labels = 0;
      switch (pcase) {
         case 1:
            // "x"
            h1->GetXaxis()->ImportAttributes(this->GetXaxis());
            labels = GetXaxis()->GetLabels();
            break;
         case 2:
            // "y"
            h1->GetXaxis()->ImportAttributes(this->GetYaxis());
            labels = GetYaxis()->GetLabels();
            break;
         case 3:
            // "z"
            h1->GetXaxis()->ImportAttributes(this->GetZaxis());
            labels = GetZaxis()->GetLabels();
            break;
      }
      if (labels) {
         TIter iL(labels);
         TObjString* lb;
         Int_t i = 1;
         while ((lb=(TObjString*)iL())) {
            h1->GetXaxis()->SetBinLabel(i,lb->String().Data());
            i++;
         }
      }
      h1->SetLineColor(this->GetLineColor());
      h1->SetFillColor(this->GetFillColor());
      h1->SetMarkerColor(this->GetMarkerColor());
      h1->SetMarkerStyle(this->GetMarkerStyle());
   }
   if (pcase >=4 && pcase <=9) {
      THashList* labels1 = 0;
      THashList* labels2 = 0;
      switch (pcase) {
         case 4:
            // "xy"
            h2->GetXaxis()->ImportAttributes(this->GetYaxis());
            h2->GetYaxis()->ImportAttributes(this->GetXaxis());
            labels1 = GetYaxis()->GetLabels();
            labels2 = GetXaxis()->GetLabels();
            break;
         case 5:
            // "yx"
            h2->GetXaxis()->ImportAttributes(this->GetXaxis());
            h2->GetYaxis()->ImportAttributes(this->GetYaxis());
            labels1 = GetXaxis()->GetLabels();
            labels2 = GetYaxis()->GetLabels();
            break;
         case 6:
            // "xz"
            h2->GetXaxis()->ImportAttributes(this->GetZaxis());
            h2->GetYaxis()->ImportAttributes(this->GetXaxis());
            labels1 = GetZaxis()->GetLabels();
            labels2 = GetXaxis()->GetLabels();
            break;
         case 7:
            // "zx"
            h2->GetXaxis()->ImportAttributes(this->GetXaxis());
            h2->GetYaxis()->ImportAttributes(this->GetZaxis());
            labels1 = GetXaxis()->GetLabels();
            labels2 = GetZaxis()->GetLabels();
            break;
         case 8:
            // "yz"
            h2->GetXaxis()->ImportAttributes(this->GetZaxis());
            h2->GetYaxis()->ImportAttributes(this->GetYaxis());
            labels1 = GetZaxis()->GetLabels();
            labels2 = GetYaxis()->GetLabels();
            break;
         case 9:
            // "zy"
            h2->GetXaxis()->ImportAttributes(this->GetYaxis());
            h2->GetYaxis()->ImportAttributes(this->GetZaxis());
            labels1 = GetYaxis()->GetLabels();
            labels2 = GetZaxis()->GetLabels();
            break;
      }
      if (labels1) {
         TIter iL(labels1);
         TObjString* lb;
         Int_t i = 1;
         while ((lb=(TObjString*)iL())) {
            h2->GetXaxis()->SetBinLabel(i,lb->String().Data());
            i++;
         }
      }
      if (labels2) {
         TIter iL(labels2);
         TObjString* lb;
         Int_t i = 1;
         while ((lb=(TObjString*)iL())) {
            h2->GetYaxis()->SetBinLabel(i,lb->String().Data());
            i++;
         }
      }
      h2->SetLineColor(this->GetLineColor());
      h2->SetFillColor(this->GetFillColor());
      h2->SetMarkerColor(this->GetMarkerColor());
      h2->SetMarkerStyle(this->GetMarkerStyle());
   }

   delete [] name;
   delete [] title;
   TH1 *h = h1;
   if (h2) h = h2;
   if (h == 0) return 0;

   Bool_t computeErrors = kFALSE;
   if (opt.Contains("e") || GetSumw2N() ) {h->Sumw2(); computeErrors = kTRUE;}

   bool useUF = !opt.Contains("nuf");
   bool useOF = !opt.Contains("nof");
   // Fill the projected histogram excluding underflow/overflows if considered in the option
   // if specified in the option (by default they considered)
   if (!fXaxis.TestBit(TAxis::kAxisRange)) {
      if (useUF) ixmin--; 
      if (useOF) ixmax++; 
   }
   if (!fYaxis.TestBit(TAxis::kAxisRange)) {
      if (useUF) iymin--; 
      if (useOF) iymax++;
   }
   if (!fZaxis.TestBit(TAxis::kAxisRange)) {
      if (useUF) izmin--; 
      if (useOF) izmax++;
   }

   Double_t cont,e,e1;
   Double_t entries  = 0;
   Double_t newerror = 0;
   for (Int_t ixbin=0;ixbin<=1+fXaxis.GetNbins();ixbin++){
      Int_t ix = ixbin-ixmin+1;
      if (ix < 0) ix=0; if (ix > nx+1) ix = nx+1;
      for (Int_t iybin=0;iybin<=1+fYaxis.GetNbins();iybin++){
         Int_t iy = iybin-iymin+1;
         if (iy < 0) iy=0; if (iy > ny+1) iy = ny+1;
         for (Int_t izbin=0;izbin<=1+fZaxis.GetNbins();izbin++){
            Int_t iz = izbin-izmin+1;
            if (iz < 0) iz=0; if (iz > nz+1) iz = nz+1;
            Int_t bin = GetBin(ixbin,iybin,izbin);
            cont = GetBinContent(bin);
            switch (pcase) {
               case 1:
                  // "x"
                  if (iybin < iymin || iybin > iymax) continue;
                  if (izbin < izmin || izbin > izmax) continue;
                  e1       = h1->GetBinError(ix);
                  if (cont) h1->Fill(fXaxis.GetBinCenter(ixbin), cont);
                  if (computeErrors) {
                     e        = GetBinError(bin);
                     newerror = TMath::Sqrt(e*e + e1*e1);
                     h1->SetBinError(ix,newerror);
                  }
                  break;

               case 2:
                  // "y"
                  if (ixbin < ixmin || ixbin > ixmax) continue;
                  if (izbin < izmin || izbin > izmax) continue;
                  e1       = h1->GetBinError(iy);
                  if (cont) h1->Fill(fYaxis.GetBinCenter(iybin), cont);
                  if (computeErrors) {
                     e        = GetBinError(bin);
                     newerror = TMath::Sqrt(e*e + e1*e1);
                     h1->SetBinError(iy,newerror);
                  }
                  break;

               case 3:
                  // "z"
                  if (ixbin < ixmin || ixbin > ixmax) continue;
                  if (iybin < iymin || iybin > iymax) continue;
                  e1       = h1->GetBinError(iz);
                  if (cont) h1->Fill(fZaxis.GetBinCenter(izbin), cont);
                  if (computeErrors) {
                     e        = GetBinError(bin);
                     newerror = TMath::Sqrt(e*e + e1*e1);
                     h1->SetBinError(iz,newerror);
                  }
                  break;

               case 4:
                  // "xy"
                  if (izbin < izmin || izbin > izmax) continue;
                  e1       = h2->GetCellError(iy,ix);
                  if (cont) h2->Fill(fYaxis.GetBinCenter(iybin),fXaxis.GetBinCenter(ixbin), cont);
                  if (computeErrors) {
                     e        = GetBinError(bin);
                     newerror = TMath::Sqrt(e*e + e1*e1);
                     h2->SetCellError(iy,ix,newerror);
                  }
                  break;

               case 5:
                  // "yx"
                  if (izbin < izmin || izbin > izmax) continue;
                  e1       = h2->GetCellError(ix,iy);
                  if (cont) h2->Fill(fXaxis.GetBinCenter(ixbin),fYaxis.GetBinCenter(iybin), cont);
                  if (computeErrors) {
                     e        = GetBinError(bin);
                     newerror = TMath::Sqrt(e*e + e1*e1);
                     h2->SetCellError(ix,iy,newerror);
                  }
                  break;

               case 6:
                  // "xz"
                  if (iybin < iymin || iybin > iymax) continue;
                  e1       = h2->GetCellError(iz,ix);
                  if (cont) h2->Fill(fZaxis.GetBinCenter(izbin),fXaxis.GetBinCenter(ixbin), cont);
                  if (computeErrors) {
                     e        = GetBinError(bin);
                     newerror = TMath::Sqrt(e*e + e1*e1);
                     h2->SetCellError(iz,ix,newerror);
                  }
                  break;

               case 7:
                  // "zx"
                  if (iybin < iymin || iybin > iymax) continue;
                  e1       = h2->GetCellError(ix,iz);
                  if (cont) h2->Fill(fXaxis.GetBinCenter(ixbin),fZaxis.GetBinCenter(izbin), cont);
                  if (computeErrors) {
                     e        = GetBinError(bin);
                     newerror = TMath::Sqrt(e*e + e1*e1);
                     h2->SetCellError(ix,iz,newerror);
                  }
                  break;

               case 8:
                  // "yz"
                  if (ixbin < ixmin || ixbin > ixmax) continue;
                  e1       = h2->GetCellError(iz,iy);
                  if (cont) h2->Fill(fZaxis.GetBinCenter(izbin),fYaxis.GetBinCenter(iybin), cont);
                  if (computeErrors) {
                     e        = GetBinError(bin);
                     newerror = TMath::Sqrt(e*e + e1*e1);
                     h2->SetCellError(iz,iy,newerror);
                  }
                  break;

               case 9:
                  // "zy"
                  if (ixbin < ixmin || ixbin > ixmax) continue;
                  e1       = h2->GetCellError(iy,iz);
                  if (cont) h2->Fill(fYaxis.GetBinCenter(iybin),fZaxis.GetBinCenter(izbin), cont);
                  if (computeErrors) {
                     e        = GetBinError(bin);
                     newerror = TMath::Sqrt(e*e + e1*e1);
                     h2->SetCellError(iy,iz,newerror);
                  }
                  break;
            }
            if (cont) {
               if (computeErrors) {
                  e   = GetBinError(bin);
                  Double_t e2 = e * e;
                  if (e2 > 0) entries += cont*cont/e2;
               }
               else
                  entries += cont;
            }
         }
      }
   }
   h->SetEntries(entries);
   return h;
}

//______________________________________________________________________________
TProfile2D *TH3::Project3DProfile(Option_t *option) const
{
   // Project a 3-d histogram into a 2-d profile histograms depending
   // on the option parameter
   // option may contain a combination of the characters x,y,z
   // option = "xy" return the x versus y projection into a TProfile2D histogram
   // option = "yx" return the y versus x projection into a TProfile2D histogram
   // option = "xz" return the x versus z projection into a TProfile2D histogram
   // option = "zx" return the z versus x projection into a TProfile2D histogram
   // option = "yz" return the y versus z projection into a TProfile2D histogram
   // option = "zy" return the z versus y projection into a TProfile2D histogram
   //
   // The projection is made for the selected bins only.
   // To select a bin range along an axis, use TAxis::SetRange, eg
   //    h3.GetYaxis()->SetRange(23,56);
   //
   // NOTE 1: The generated histogram is named th3name + _poption
   // eg if the TH3* h histogram is named "myhist", then
   // h->Project3D("xy"); produces a TProfile2D histogram named "myhist_pxy"
   // if a histogram of the same type already exists, it is deleted.
   // The following sequence
   //    h->Project3DProfile("xy");
   //    h->Project3DProfile("xy2");
   //  will generate two TProfile2D histograms named "myhist_pxy" and "myhist_pxy2"
   //
   //  NOTE 2: The number of entries in the projected profile is estimated from the number of 
   //  effective entries for all the cells included in the projection. 
   //
   //  NOTE 3: underflow/overflow are by default excluded from the projection 
   //  (Note that this is a different default behavior compared to the projection to an histogram) 
   //  To exclude underflow and/or overflow (for both axis in case of a projection to a 1D histogram) use option "UF" and/or "OF"

   TString opt = option; opt.ToLower();
   Int_t ixmin = fXaxis.GetFirst();
   Int_t ixmax = fXaxis.GetLast();
   Int_t iymin = fYaxis.GetFirst();
   Int_t iymax = fYaxis.GetLast();
   Int_t izmin = fZaxis.GetFirst();
   Int_t izmax = fZaxis.GetLast();
   Int_t nx = ixmax-ixmin+1;
   Int_t ny = iymax-iymin+1;
   Int_t nz = izmax-izmin+1;
   Int_t pcase = 0;
   if (opt.Contains("xy")) pcase = 4;
   if (opt.Contains("yx")) pcase = 5;
   if (opt.Contains("xz")) pcase = 6;
   if (opt.Contains("zx")) pcase = 7;
   if (opt.Contains("yz")) pcase = 8;
   if (opt.Contains("zy")) pcase = 9;

   // Create the projection histogram
   TProfile2D *p2 = 0;
   Int_t nch = strlen(GetName()) +opt.Length() +3;
   char *name = new char[nch];
   sprintf(name,"%s_p%s",GetName(),option);
   nch = strlen(GetTitle()) +opt.Length() +3;
   char *title = new char[nch];
   sprintf(title,"%s_p%s",GetTitle(),option);
   delete gROOT->FindObject(name);
   const TArrayD *xbins;
   const TArrayD *ybins;
   const TArrayD *zbins;
   switch (pcase) {
      case 4:
         // "xy"
         xbins = fXaxis.GetXbins();
         ybins = fYaxis.GetXbins();
         if (xbins->fN == 0 && ybins->fN == 0) {
            p2 = new TProfile2D(name,title,ny,fYaxis.GetBinLowEdge(iymin),fYaxis.GetBinUpEdge(iymax)
               ,nx,fXaxis.GetBinLowEdge(ixmin),fXaxis.GetBinUpEdge(ixmax));
         } else if (ybins->fN == 0) {
            p2 = new TProfile2D(name,title,ny,fYaxis.GetBinLowEdge(iymin),fYaxis.GetBinUpEdge(iymax)
               ,nx,&xbins->fArray[ixmin-1]);
         } else if (xbins->fN == 0) {
            p2 = new TProfile2D(name,title,ny,&ybins->fArray[iymin-1]
            ,nx,fXaxis.GetBinLowEdge(ixmin),fXaxis.GetBinUpEdge(ixmax));
         } else {
            p2 = new TProfile2D(name,title,ny,&ybins->fArray[iymin-1],nx,&xbins->fArray[ixmin-1]);
         }
         break;

      case 5:
         // "yx"
         xbins = fXaxis.GetXbins();
         ybins = fYaxis.GetXbins();
         if (xbins->fN == 0 && ybins->fN == 0) {
            p2 = new TProfile2D(name,title,nx,fXaxis.GetBinLowEdge(ixmin),fXaxis.GetBinUpEdge(ixmax)
               ,ny,fYaxis.GetBinLowEdge(iymin),fYaxis.GetBinUpEdge(iymax));
         } else if (xbins->fN == 0) {
            p2 = new TProfile2D(name,title,nx,fXaxis.GetBinLowEdge(ixmin),fXaxis.GetBinUpEdge(ixmax)
               ,ny,&ybins->fArray[iymin-1]);
         } else if (ybins->fN == 0) {
            p2 = new TProfile2D(name,title,nx,&xbins->fArray[ixmin-1]
            ,ny,fYaxis.GetBinLowEdge(iymin),fYaxis.GetBinUpEdge(iymax));
         } else {
            p2 = new TProfile2D(name,title,nx,&xbins->fArray[ixmin-1],ny,&ybins->fArray[iymin-1]);
         }
         break;

      case 6:
         // "xz"
         xbins = fXaxis.GetXbins();
         zbins = fZaxis.GetXbins();
         if (xbins->fN == 0 && zbins->fN == 0) {
            p2 = new TProfile2D(name,title,nz,fZaxis.GetBinLowEdge(izmin),fZaxis.GetBinUpEdge(izmax)
               ,nx,fXaxis.GetBinLowEdge(ixmin),fXaxis.GetBinUpEdge(ixmax));
         } else if (zbins->fN == 0) {
            p2 = new TProfile2D(name,title,nz,fZaxis.GetBinLowEdge(izmin),fZaxis.GetBinUpEdge(izmax)
               ,nx,&xbins->fArray[ixmin-1]);
         } else if (xbins->fN == 0) {
            p2 = new TProfile2D(name,title,nz,&zbins->fArray[izmin-1]
            ,nx,fXaxis.GetBinLowEdge(ixmin),fXaxis.GetBinUpEdge(ixmax));
         } else {
            p2 = new TProfile2D(name,title,nz,&zbins->fArray[izmin-1],nx,&xbins->fArray[ixmin-1]);
         }
         break;

      case 7:
         // "zx"
         xbins = fXaxis.GetXbins();
         zbins = fZaxis.GetXbins();
         if (xbins->fN == 0 && zbins->fN == 0) {
            p2 = new TProfile2D(name,title,nx,fXaxis.GetBinLowEdge(ixmin),fXaxis.GetBinUpEdge(ixmax)
               ,nz,fZaxis.GetBinLowEdge(izmin),fZaxis.GetBinUpEdge(izmax));
         } else if (xbins->fN == 0) {
            p2 = new TProfile2D(name,title,nx,fXaxis.GetBinLowEdge(ixmin),fXaxis.GetBinUpEdge(ixmax)
               ,nz,&zbins->fArray[izmin-1]);
         } else if (zbins->fN == 0) {
            p2 = new TProfile2D(name,title,nx,&xbins->fArray[ixmin-1]
            ,nz,fZaxis.GetBinLowEdge(izmin),fZaxis.GetBinUpEdge(izmax));
         } else {
            p2 = new TProfile2D(name,title,nx,&xbins->fArray[ixmin-1],nz,&zbins->fArray[izmin-1]);
         }
         break;

      case 8:
         // "yz"
         ybins = fYaxis.GetXbins();
         zbins = fZaxis.GetXbins();
         if (ybins->fN == 0 && zbins->fN == 0) {
            p2 = new TProfile2D(name,title,nz,fZaxis.GetBinLowEdge(izmin),fZaxis.GetBinUpEdge(izmax)
               ,ny,fYaxis.GetBinLowEdge(iymin),fYaxis.GetBinUpEdge(iymax));
         } else if (zbins->fN == 0) {
            p2 = new TProfile2D(name,title,nz,fZaxis.GetBinLowEdge(izmin),fZaxis.GetBinUpEdge(izmax)
               ,ny,&ybins->fArray[iymin-1]);
         } else if (ybins->fN == 0) {
            p2 = new TProfile2D(name,title,nz,&zbins->fArray[izmin-1]
            ,ny,fYaxis.GetBinLowEdge(iymin),fYaxis.GetBinUpEdge(iymax));
         } else {
            p2 = new TProfile2D(name,title,nz,&zbins->fArray[izmin-1],ny,&ybins->fArray[iymin-1]);
         }
         break;

      case 9:
         // "zy"
         ybins = fYaxis.GetXbins();
         zbins = fZaxis.GetXbins();
         if (ybins->fN == 0 && zbins->fN == 0) {
            p2 = new TProfile2D(name,title,ny,fYaxis.GetBinLowEdge(iymin),fYaxis.GetBinUpEdge(iymax)
               ,nz,fZaxis.GetBinLowEdge(izmin),fZaxis.GetBinUpEdge(izmax));
         } else if (ybins->fN == 0) {
            p2 = new TProfile2D(name,title,ny,fYaxis.GetBinLowEdge(iymin),fYaxis.GetBinUpEdge(iymax)
               ,nz,&zbins->fArray[izmin-1]);
         } else if (zbins->fN == 0) {
            p2 = new TProfile2D(name,title,ny,&ybins->fArray[iymin-1]
            ,nz,fZaxis.GetBinLowEdge(izmin),fZaxis.GetBinUpEdge(izmax));
         } else {
            p2 = new TProfile2D(name,title,ny,&ybins->fArray[iymin-1],nz,&zbins->fArray[izmin-1]);
         }
         break;

   }

   delete [] name;
   delete [] title;
   if (p2 == 0) return 0;

   bool useUF = opt.Contains("uf");
   bool useOF = opt.Contains("of");
   // Fill the projected histogram taking into accounts underflow/overflows
   if (!fXaxis.TestBit(TAxis::kAxisRange)) {
      if (useUF) ixmin--; 
      if (useOF) ixmax++; 
   }
   if (!fYaxis.TestBit(TAxis::kAxisRange)) {
      if (useUF) iymin--; 
      if (useOF) iymax++;
   }
   if (!fZaxis.TestBit(TAxis::kAxisRange)) {
      if (useUF) izmin--; 
      if (useOF) izmax++;
   }
   Double_t cont;
   Double_t entries  = 0;
   for (Int_t ixbin=0;ixbin<=1+fXaxis.GetNbins();ixbin++){
      for (Int_t iybin=0;iybin<=1+fYaxis.GetNbins();iybin++){
         for (Int_t izbin=0;izbin<=1+fZaxis.GetNbins();izbin++){
            Int_t bin = GetBin(ixbin,iybin,izbin);
            cont = GetBinContent(bin);
            switch (pcase) {
               case 4:
                  // "xy"
                  if (izbin < izmin || izbin > izmax) continue;
                  if (cont) p2->Fill(fYaxis.GetBinCenter(iybin),fXaxis.GetBinCenter(ixbin),fZaxis.GetBinCenter(izbin), cont);
                  break;

               case 5:
                  // "yx"
                  if (izbin < izmin || izbin > izmax) continue;
                  if (cont) p2->Fill(fXaxis.GetBinCenter(ixbin),fYaxis.GetBinCenter(iybin),fZaxis.GetBinCenter(izbin), cont);
                  break;

               case 6:
                  // "xz"
                  if (iybin < iymin || iybin > iymax) continue;
                  if (cont) p2->Fill(fZaxis.GetBinCenter(izbin),fXaxis.GetBinCenter(ixbin),fYaxis.GetBinCenter(iybin), cont);
                  break;

               case 7:
                  // "zx"
                  if (iybin < iymin || iybin > iymax) continue;
                  if (cont) p2->Fill(fXaxis.GetBinCenter(ixbin),fZaxis.GetBinCenter(izbin),fYaxis.GetBinCenter(iybin), cont);
                  break;

               case 8:
                  // "yz"
                  if (ixbin < ixmin || ixbin > ixmax) continue;
                  if (cont) p2->Fill(fZaxis.GetBinCenter(izbin),fYaxis.GetBinCenter(iybin),fXaxis.GetBinCenter(ixbin), cont);
                  break;

               case 9:
                  // "zy"
                  if (ixbin < ixmin || ixbin > ixmax) continue;
                  if (cont) p2->Fill(fYaxis.GetBinCenter(iybin),fZaxis.GetBinCenter(izbin),fXaxis.GetBinCenter(ixbin), cont);
                  break;
            }
            if (cont) {
               // count total effective entries of the profile
               Double_t err = GetBinError(bin);
               entries += cont*cont/(err*err);
            }
         }
      }
   }
   p2->SetEntries(entries);
   return p2;
}

//______________________________________________________________________________
void TH3::PutStats(Double_t *stats)
{
   // Replace current statistics with the values in array stats

   TH1::PutStats(stats);
   fTsumwy  = stats[4];
   fTsumwy2 = stats[5];
   fTsumwxy = stats[6];
   fTsumwz  = stats[7];
   fTsumwz2 = stats[8];
   fTsumwxz = stats[9];
   fTsumwyz = stats[10];
}

//______________________________________________________________________________
void TH3::Reset(Option_t *option)
{
   //*-*-*-*-*-*-*-*Reset this histogram: contents, errors, etc*-*-*-*-*-*-*-*
   //*-*            ===========================================

   TH1::Reset(option);
   TString opt = option;
   opt.ToUpper();
   if (opt.Contains("ICE")) return;
   fTsumwy  = 0;
   fTsumwy2 = 0;
   fTsumwxy = 0;
   fTsumwz  = 0;
   fTsumwz2 = 0;
   fTsumwxz = 0;
   fTsumwyz = 0;
}

//______________________________________________________________________________
void TH3::Streamer(TBuffer &R__b)
{
   // Stream an object of class TH3.

   if (R__b.IsReading()) {
      UInt_t R__s, R__c;
      Version_t R__v = R__b.ReadVersion(&R__s, &R__c);
      if (R__v > 2) {
         R__b.ReadClassBuffer(TH3::Class(), this, R__v, R__s, R__c);
         return;
      }
      //====process old versions before automatic schema evolution
      TH1::Streamer(R__b);
      TAtt3D::Streamer(R__b);
      R__b.CheckByteCount(R__s, R__c, TH3::IsA());
      //====end of old versions

   } else {
      R__b.WriteClassBuffer(TH3::Class(),this);
   }
}



//______________________________________________________________________________
//                     TH3C methods
//  TH3C a 3-D histogram with one byte per cell (char)
//______________________________________________________________________________

ClassImp(TH3C)

//______________________________________________________________________________
TH3C::TH3C(): TH3(), TArrayC(1)
{
   // Constructor.
}

//______________________________________________________________________________
TH3C::~TH3C()
{
   // Destructor.
}

//______________________________________________________________________________
TH3C::TH3C(const char *name,const char *title,Int_t nbinsx,Double_t xlow,Double_t xup
           ,Int_t nbinsy,Double_t ylow,Double_t yup
           ,Int_t nbinsz,Double_t zlow,Double_t zup)
           :TH3(name,title,nbinsx,xlow,xup,nbinsy,ylow,yup,nbinsz,zlow,zup)
{
   //*-*-*-*-*-*-*-*-*Normal constructor for fix bin size 3-D histograms*-*-*-*-*
   //*-*              ==================================================

   TArrayC::Set(fNcells);
   if (fgDefaultSumw2) Sumw2();

   //if (xlow >= xup || ylow >= yup || zlow >= zup) SetBuffer(fgBufferSize);
}

//______________________________________________________________________________
TH3C::TH3C(const char *name,const char *title,Int_t nbinsx,const Float_t *xbins
           ,Int_t nbinsy,const Float_t *ybins
           ,Int_t nbinsz,const Float_t *zbins)
           :TH3(name,title,nbinsx,xbins,nbinsy,ybins,nbinsz,zbins)
{
   //*-*-*-*-*-*-*-*Normal constructor for variable bin size 3-D histograms*-*-*-*
   //*-*            =======================================================
   TArrayC::Set(fNcells);
   if (fgDefaultSumw2) Sumw2();
}

//______________________________________________________________________________
TH3C::TH3C(const char *name,const char *title,Int_t nbinsx,const Double_t *xbins
           ,Int_t nbinsy,const Double_t *ybins
           ,Int_t nbinsz,const Double_t *zbins)
           :TH3(name,title,nbinsx,xbins,nbinsy,ybins,nbinsz,zbins)
{
   //*-*-*-*-*-*-*-*Normal constructor for variable bin size 3-D histograms*-*-*-*
   //*-*            =======================================================
   TArrayC::Set(fNcells);
   if (fgDefaultSumw2) Sumw2();
}

//______________________________________________________________________________
TH3C::TH3C(const TH3C &h3c) : TH3(), TArrayC()
{
   // Copy constructor.

   ((TH3C&)h3c).Copy(*this);
}

//______________________________________________________________________________
void TH3C::AddBinContent(Int_t bin)
{
   //*-*-*-*-*-*-*-*-*-*Increment bin content by 1*-*-*-*-*-*-*-*-*-*-*-*-*-*
   //*-*                ==========================

   if (fArray[bin] < 127) fArray[bin]++;
}

//______________________________________________________________________________
void TH3C::AddBinContent(Int_t bin, Double_t w)
{
   //*-*-*-*-*-*-*-*-*-*Increment bin content by w*-*-*-*-*-*-*-*-*-*-*-*-*-*
   //*-*                ==========================

   Int_t newval = fArray[bin] + Int_t(w);
   if (newval > -128 && newval < 128) {fArray[bin] = Char_t(newval); return;}
   if (newval < -127) fArray[bin] = -127;
   if (newval >  127) fArray[bin] =  127;
}

//______________________________________________________________________________
void TH3C::Copy(TObject &newth3) const
{
   //*-*-*-*-*-*-*Copy this 3-D histogram structure to newth3*-*-*-*-*-*-*-*-*-*
   //*-*          ===========================================

   TH3::Copy((TH3C&)newth3);
}

//______________________________________________________________________________
TH1 *TH3C::DrawCopy(Option_t *option) const
{
   // Draw copy.

   TString opt = option;
   opt.ToLower();
   if (gPad && !opt.Contains("same")) gPad->Clear();
   TH3C *newth3 = (TH3C*)Clone();
   newth3->SetDirectory(0);
   newth3->SetBit(kCanDelete);
   newth3->AppendPad(option);
   return newth3;
}

//______________________________________________________________________________
Double_t TH3C::GetBinContent(Int_t bin) const
{
   // Get bin content.

   if (fBuffer) ((TH3C*)this)->BufferEmpty();
   if (bin < 0) bin = 0;
   if (bin >= fNcells) bin = fNcells-1;
   if (!fArray) return 0;
   return Double_t (fArray[bin]);
}

//______________________________________________________________________________
void TH3C::Reset(Option_t *option)
{
   //*-*-*-*-*-*-*-*Reset this histogram: contents, errors, etc*-*-*-*-*-*-*-*
   //*-*            ===========================================

   TH3::Reset(option);
   TArrayC::Reset();
   // should also reset statistics once statistics are implemented for TH3
}

//______________________________________________________________________________
void TH3C::SetBinsLength(Int_t n)
{
   // Set total number of bins including under/overflow
   // Reallocate bin contents array

   if (n < 0) n = (fXaxis.GetNbins()+2)*(fYaxis.GetNbins()+2)*(fZaxis.GetNbins()+2);
   fNcells = n;
   TArrayC::Set(n);
}

//______________________________________________________________________________
void TH3C::SetBinContent(Int_t bin, Double_t content)
{
   // Set bin content
   if (bin < 0) return;
   if (bin >= fNcells) return;
   fArray[bin] = Char_t (content);
   fEntries++;
   fTsumw = 0;
}


//______________________________________________________________________________
void TH3::SetShowProjection(const char *option,Int_t nbins)
{
   // When the mouse is moved in a pad containing a 3-d view of this histogram
   // a second canvas shows a projection type given as option.
   // To stop the generation of the projections, delete the canvas
   // containing the projection.
   // option may contain a combination of the characters x,y,z,e
   // option = "x" return the x projection into a TH1D histogram
   // option = "y" return the y projection into a TH1D histogram
   // option = "z" return the z projection into a TH1D histogram
   // option = "xy" return the x versus y projection into a TH2D histogram
   // option = "yx" return the y versus x projection into a TH2D histogram
   // option = "xz" return the x versus z projection into a TH2D histogram
   // option = "zx" return the z versus x projection into a TH2D histogram
   // option = "yz" return the y versus z projection into a TH2D histogram
   // option = "zy" return the z versus y projection into a TH2D histogram
   // option can also include the drawing option for the projection, eg to draw
   // the xy projection using the draw option "box" do
   //   myhist.SetShowProjection("xy box");
   // This function is typically called from the context menu.

   GetPainter();

   if (fPainter) fPainter->SetShowProjection(option,nbins);
}

//______________________________________________________________________________
void TH3C::Streamer(TBuffer &R__b)
{
   // Stream an object of class TH3C.

   if (R__b.IsReading()) {
      UInt_t R__s, R__c;
      if (R__b.GetParent() && R__b.GetVersionOwner() < 22300) return;
      Version_t R__v = R__b.ReadVersion(&R__s, &R__c);
      if (R__v > 2) {
         R__b.ReadClassBuffer(TH3C::Class(), this, R__v, R__s, R__c);
         return;
      }
      //====process old versions before automatic schema evolution
      if (R__v < 2) {
         R__b.ReadVersion();
         TH1::Streamer(R__b);
         TArrayC::Streamer(R__b);
         R__b.ReadVersion(&R__s, &R__c);
         TAtt3D::Streamer(R__b);
      } else {
         TH3::Streamer(R__b);
         TArrayC::Streamer(R__b);
         R__b.CheckByteCount(R__s, R__c, TH3C::IsA());
      }
      //====end of old versions

   } else {
      R__b.WriteClassBuffer(TH3C::Class(),this);
   }
}

//______________________________________________________________________________
TH3C& TH3C::operator=(const TH3C &h1)
{
   // Operator =

   if (this != &h1)  ((TH3C&)h1).Copy(*this);
   return *this;
}

//______________________________________________________________________________
TH3C operator*(Float_t c1, TH3C &h1)
{
   // Operator *

   TH3C hnew = h1;
   hnew.Scale(c1);
   hnew.SetDirectory(0);
   return hnew;
}

//______________________________________________________________________________
TH3C operator+(TH3C &h1, TH3C &h2)
{
   // Operator +

   TH3C hnew = h1;
   hnew.Add(&h2,1);
   hnew.SetDirectory(0);
   return hnew;
}

//______________________________________________________________________________
TH3C operator-(TH3C &h1, TH3C &h2)
{
   // Operator -

   TH3C hnew = h1;
   hnew.Add(&h2,-1);
   hnew.SetDirectory(0);
   return hnew;
}

//______________________________________________________________________________
TH3C operator*(TH3C &h1, TH3C &h2)
{
   // Operator *

   TH3C hnew = h1;
   hnew.Multiply(&h2);
   hnew.SetDirectory(0);
   return hnew;
}

//______________________________________________________________________________
TH3C operator/(TH3C &h1, TH3C &h2)
{
   // Operator /

   TH3C hnew = h1;
   hnew.Divide(&h2);
   hnew.SetDirectory(0);
   return hnew;
}


//______________________________________________________________________________
//                     TH3S methods
//  TH3S a 3-D histogram with two bytes per cell (short integer)
//______________________________________________________________________________

ClassImp(TH3S)

//______________________________________________________________________________
TH3S::TH3S(): TH3(), TArrayS(1)
{
   // Constructor.
}

//______________________________________________________________________________
TH3S::~TH3S()
{
   // Destructor.
}

//______________________________________________________________________________
TH3S::TH3S(const char *name,const char *title,Int_t nbinsx,Double_t xlow,Double_t xup
           ,Int_t nbinsy,Double_t ylow,Double_t yup
           ,Int_t nbinsz,Double_t zlow,Double_t zup)
           :TH3(name,title,nbinsx,xlow,xup,nbinsy,ylow,yup,nbinsz,zlow,zup)
{
   //*-*-*-*-*-*-*-*-*Normal constructor for fix bin size 3-D histograms*-*-*-*-*
   //*-*              ==================================================
   TH3S::Set(fNcells);
   if (fgDefaultSumw2) Sumw2();

   //if (xlow >= xup || ylow >= yup || zlow >= zup) SetBuffer(fgBufferSize);
}

//______________________________________________________________________________
TH3S::TH3S(const char *name,const char *title,Int_t nbinsx,const Float_t *xbins
           ,Int_t nbinsy,const Float_t *ybins
           ,Int_t nbinsz,const Float_t *zbins)
           :TH3(name,title,nbinsx,xbins,nbinsy,ybins,nbinsz,zbins)
{
   //*-*-*-*-*-*-*-*Normal constructor for variable bin size 3-D histograms*-*-*-*
   //*-*            =======================================================
   TH3S::Set(fNcells);
   if (fgDefaultSumw2) Sumw2();
}

//______________________________________________________________________________
TH3S::TH3S(const char *name,const char *title,Int_t nbinsx,const Double_t *xbins
           ,Int_t nbinsy,const Double_t *ybins
           ,Int_t nbinsz,const Double_t *zbins)
           :TH3(name,title,nbinsx,xbins,nbinsy,ybins,nbinsz,zbins)
{
   //*-*-*-*-*-*-*-*Normal constructor for variable bin size 3-D histograms*-*-*-*
   //*-*            =======================================================
   TH3S::Set(fNcells);
   if (fgDefaultSumw2) Sumw2();
}

//______________________________________________________________________________
TH3S::TH3S(const TH3S &h3s) : TH3(), TArrayS()
{
   // Copy Constructor.

   ((TH3S&)h3s).Copy(*this);
}

//______________________________________________________________________________
void TH3S::AddBinContent(Int_t bin)
{
   //*-*-*-*-*-*-*-*-*-*Increment bin content by 1*-*-*-*-*-*-*-*-*-*-*-*-*-*
   //*-*                ==========================

   if (fArray[bin] < 32767) fArray[bin]++;
}

//______________________________________________________________________________
void TH3S::AddBinContent(Int_t bin, Double_t w)
{
   //*-*-*-*-*-*-*-*-*-*Increment bin content by w*-*-*-*-*-*-*-*-*-*-*-*-*-*
   //*-*                ==========================

   Int_t newval = fArray[bin] + Int_t(w);
   if (newval > -32768 && newval < 32768) {fArray[bin] = Short_t(newval); return;}
   if (newval < -32767) fArray[bin] = -32767;
   if (newval >  32767) fArray[bin] =  32767;
}

//______________________________________________________________________________
void TH3S::Copy(TObject &newth3) const
{
   //*-*-*-*-*-*-*Copy this 3-D histogram structure to newth3*-*-*-*-*-*-*-*-*-*
   //*-*          ===========================================

   TH3::Copy((TH3S&)newth3);
}

//______________________________________________________________________________
TH1 *TH3S::DrawCopy(Option_t *option) const
{
   // Draw copy.

   TString opt = option;
   opt.ToLower();
   if (gPad && !opt.Contains("same")) gPad->Clear();
   TH3S *newth3 = (TH3S*)Clone();
   newth3->SetDirectory(0);
   newth3->SetBit(kCanDelete);
   newth3->AppendPad(option);
   return newth3;
}

//______________________________________________________________________________
Double_t TH3S::GetBinContent(Int_t bin) const
{
   // Get bin content.

   if (fBuffer) ((TH3S*)this)->BufferEmpty();
   if (bin < 0) bin = 0;
   if (bin >= fNcells) bin = fNcells-1;
   if (!fArray) return 0;
   return Double_t (fArray[bin]);
}

//______________________________________________________________________________
void TH3S::Reset(Option_t *option)
{
   //*-*-*-*-*-*-*-*Reset this histogram: contents, errors, etc*-*-*-*-*-*-*-*
   //*-*            ===========================================

   TH3::Reset(option);
   TArrayS::Reset();
   // should also reset statistics once statistics are implemented for TH3
}

//______________________________________________________________________________
void TH3S::SetBinContent(Int_t bin, Double_t content)
{
   // Set bin content
   if (bin < 0) return;
   if (bin >= fNcells) return;
   fArray[bin] = Short_t (content);
   fEntries++;
   fTsumw = 0;
}

//______________________________________________________________________________
void TH3S::SetBinsLength(Int_t n)
{
   // Set total number of bins including under/overflow
   // Reallocate bin contents array

   if (n < 0) n = (fXaxis.GetNbins()+2)*(fYaxis.GetNbins()+2)*(fZaxis.GetNbins()+2);
   fNcells = n;
   TArrayS::Set(n);
}

//______________________________________________________________________________
void TH3S::Streamer(TBuffer &R__b)
{
   // Stream an object of class TH3S.

   if (R__b.IsReading()) {
      UInt_t R__s, R__c;
      if (R__b.GetParent() && R__b.GetVersionOwner() < 22300) return;
      Version_t R__v = R__b.ReadVersion(&R__s, &R__c);
      if (R__v > 2) {
         R__b.ReadClassBuffer(TH3S::Class(), this, R__v, R__s, R__c);
         return;
      }
      //====process old versions before automatic schema evolution
      if (R__v < 2) {
         R__b.ReadVersion();
         TH1::Streamer(R__b);
         TArrayS::Streamer(R__b);
         R__b.ReadVersion(&R__s, &R__c);
         TAtt3D::Streamer(R__b);
      } else {
         TH3::Streamer(R__b);
         TArrayS::Streamer(R__b);
         R__b.CheckByteCount(R__s, R__c, TH3S::IsA());
      }
      //====end of old versions

   } else {
      R__b.WriteClassBuffer(TH3S::Class(),this);
   }
}

//______________________________________________________________________________
TH3S& TH3S::operator=(const TH3S &h1)
{
   // Operator =

   if (this != &h1)  ((TH3S&)h1).Copy(*this);
   return *this;
}

//______________________________________________________________________________
TH3S operator*(Float_t c1, TH3S &h1)
{
   // Operator *

   TH3S hnew = h1;
   hnew.Scale(c1);
   hnew.SetDirectory(0);
   return hnew;
}

//______________________________________________________________________________
TH3S operator+(TH3S &h1, TH3S &h2)
{
   // Operator +

   TH3S hnew = h1;
   hnew.Add(&h2,1);
   hnew.SetDirectory(0);
   return hnew;
}

//______________________________________________________________________________
TH3S operator-(TH3S &h1, TH3S &h2)
{
   // Operator -

   TH3S hnew = h1;
   hnew.Add(&h2,-1);
   hnew.SetDirectory(0);
   return hnew;
}

//______________________________________________________________________________
TH3S operator*(TH3S &h1, TH3S &h2)
{
   // Operator *

   TH3S hnew = h1;
   hnew.Multiply(&h2);
   hnew.SetDirectory(0);
   return hnew;
}

//______________________________________________________________________________
TH3S operator/(TH3S &h1, TH3S &h2)
{
   // Operator /

   TH3S hnew = h1;
   hnew.Divide(&h2);
   hnew.SetDirectory(0);
   return hnew;
}


//______________________________________________________________________________
//                     TH3I methods
//  TH3I a 3-D histogram with four bytes per cell (32 bits integer)
//______________________________________________________________________________

ClassImp(TH3I)

//______________________________________________________________________________
TH3I::TH3I(): TH3(), TArrayI(1)
{
   // Constructor.
}

//______________________________________________________________________________
TH3I::~TH3I()
{
   // Destructor.
}

//______________________________________________________________________________
TH3I::TH3I(const char *name,const char *title,Int_t nbinsx,Double_t xlow,Double_t xup
           ,Int_t nbinsy,Double_t ylow,Double_t yup
           ,Int_t nbinsz,Double_t zlow,Double_t zup)
           :TH3(name,title,nbinsx,xlow,xup,nbinsy,ylow,yup,nbinsz,zlow,zup)
{
   //*-*-*-*-*-*-*-*-*Normal constructor for fix bin size 3-D histograms*-*-*-*-*
   //*-*              ==================================================
   TH3I::Set(fNcells);
   if (fgDefaultSumw2) Sumw2();

   //if (xlow >= xup || ylow >= yup || zlow >= zup) SetBuffer(fgBufferSize);
}

//______________________________________________________________________________
TH3I::TH3I(const char *name,const char *title,Int_t nbinsx,const Float_t *xbins
           ,Int_t nbinsy,const Float_t *ybins
           ,Int_t nbinsz,const Float_t *zbins)
           :TH3(name,title,nbinsx,xbins,nbinsy,ybins,nbinsz,zbins)
{
   //*-*-*-*-*-*-*-*Normal constructor for variable bin size 3-D histograms*-*-*-*
   //*-*            =======================================================
   TArrayI::Set(fNcells);
   if (fgDefaultSumw2) Sumw2();
}

//______________________________________________________________________________
TH3I::TH3I(const char *name,const char *title,Int_t nbinsx,const Double_t *xbins
           ,Int_t nbinsy,const Double_t *ybins
           ,Int_t nbinsz,const Double_t *zbins)
           :TH3(name,title,nbinsx,xbins,nbinsy,ybins,nbinsz,zbins)
{
   //*-*-*-*-*-*-*-*Normal constructor for variable bin size 3-D histograms*-*-*-*
   //*-*            =======================================================
   TArrayI::Set(fNcells);
   if (fgDefaultSumw2) Sumw2();
}

//______________________________________________________________________________
TH3I::TH3I(const TH3I &h3i) : TH3(), TArrayI()
{
   // Copy constructor.

   ((TH3I&)h3i).Copy(*this);
}

//______________________________________________________________________________
void TH3I::AddBinContent(Int_t bin)
{
   //*-*-*-*-*-*-*-*-*-*Increment bin content by 1*-*-*-*-*-*-*-*-*-*-*-*-*-*
   //*-*                ==========================

   if (fArray[bin] < 2147483647) fArray[bin]++;
}

//______________________________________________________________________________
void TH3I::AddBinContent(Int_t bin, Double_t w)
{
   //*-*-*-*-*-*-*-*-*-*Increment bin content by w*-*-*-*-*-*-*-*-*-*-*-*-*-*
   //*-*                ==========================

   Int_t newval = fArray[bin] + Int_t(w);
   if (newval > -2147483647 && newval < 2147483647) {fArray[bin] = Int_t(newval); return;}
   if (newval < -2147483647) fArray[bin] = -2147483647;
   if (newval >  2147483647) fArray[bin] =  2147483647;
}

//______________________________________________________________________________
void TH3I::Copy(TObject &newth3) const
{
   //*-*-*-*-*-*-*Copy this 3-D histogram structure to newth3*-*-*-*-*-*-*-*-*-*
   //*-*          ===========================================

   TH3::Copy((TH3I&)newth3);
}

//______________________________________________________________________________
TH1 *TH3I::DrawCopy(Option_t *option) const
{
   // Draw copy.

   TString opt = option;
   opt.ToLower();
   if (gPad && !opt.Contains("same")) gPad->Clear();
   TH3I *newth3 = (TH3I*)Clone();
   newth3->SetDirectory(0);
   newth3->SetBit(kCanDelete);
   newth3->AppendPad(option);
   return newth3;
}

//______________________________________________________________________________
Double_t TH3I::GetBinContent(Int_t bin) const
{
   // Get bin content.

   if (fBuffer) ((TH3I*)this)->BufferEmpty();
   if (bin < 0) bin = 0;
   if (bin >= fNcells) bin = fNcells-1;
   if (!fArray) return 0;
   return Double_t (fArray[bin]);
}

//______________________________________________________________________________
void TH3I::Reset(Option_t *option)
{
   //*-*-*-*-*-*-*-*Reset this histogram: contents, errors, etc*-*-*-*-*-*-*-*
   //*-*            ===========================================

   TH3::Reset(option);
   TArrayI::Reset();
   // should also reset statistics once statistics are implemented for TH3
}

//______________________________________________________________________________
void TH3I::SetBinContent(Int_t bin, Double_t content)
{
   // Set bin content
   if (bin < 0) return;
   if (bin >= fNcells) return;
   fArray[bin] = Int_t (content);
   fEntries++;
   fTsumw = 0;
}

//______________________________________________________________________________
void TH3I::SetBinsLength(Int_t n)
{
   // Set total number of bins including under/overflow
   // Reallocate bin contents array

   if (n < 0) n = (fXaxis.GetNbins()+2)*(fYaxis.GetNbins()+2)*(fZaxis.GetNbins()+2);
   fNcells = n;
   TArrayI::Set(n);
}

//______________________________________________________________________________
TH3I& TH3I::operator=(const TH3I &h1)
{
   // Operator =

   if (this != &h1)  ((TH3I&)h1).Copy(*this);
   return *this;
}

//______________________________________________________________________________
TH3I operator*(Float_t c1, TH3I &h1)
{
   // Operator *

   TH3I hnew = h1;
   hnew.Scale(c1);
   hnew.SetDirectory(0);
   return hnew;
}

//______________________________________________________________________________
TH3I operator+(TH3I &h1, TH3I &h2)
{
   // Operator +

   TH3I hnew = h1;
   hnew.Add(&h2,1);
   hnew.SetDirectory(0);
   return hnew;
}

//______________________________________________________________________________
TH3I operator-(TH3I &h1, TH3I &h2)
{
   // Operator _

   TH3I hnew = h1;
   hnew.Add(&h2,-1);
   hnew.SetDirectory(0);
   return hnew;
}

//______________________________________________________________________________
TH3I operator*(TH3I &h1, TH3I &h2)
{
   // Operator *

   TH3I hnew = h1;
   hnew.Multiply(&h2);
   hnew.SetDirectory(0);
   return hnew;
}

//______________________________________________________________________________
TH3I operator/(TH3I &h1, TH3I &h2)
{
   // Operator /

   TH3I hnew = h1;
   hnew.Divide(&h2);
   hnew.SetDirectory(0);
   return hnew;
}


//______________________________________________________________________________
//                     TH3F methods
//  TH3F a 3-D histogram with four bytes per cell (float)
//______________________________________________________________________________

ClassImp(TH3F)

//______________________________________________________________________________
TH3F::TH3F(): TH3(), TArrayF(1)
{
   // Constructor.
}

//______________________________________________________________________________
TH3F::~TH3F()
{
   // Destructor.
}

//______________________________________________________________________________
TH3F::TH3F(const char *name,const char *title,Int_t nbinsx,Double_t xlow,Double_t xup
           ,Int_t nbinsy,Double_t ylow,Double_t yup
           ,Int_t nbinsz,Double_t zlow,Double_t zup)
           :TH3(name,title,nbinsx,xlow,xup,nbinsy,ylow,yup,nbinsz,zlow,zup)
{
   //*-*-*-*-*-*-*-*-*Normal constructor for fix bin size 3-D histograms*-*-*-*-*
   //*-*              ==================================================
   TArrayF::Set(fNcells);
   if (fgDefaultSumw2) Sumw2();

   //if (xlow >= xup || ylow >= yup || zlow >= zup) SetBuffer(fgBufferSize);
}

//______________________________________________________________________________
TH3F::TH3F(const char *name,const char *title,Int_t nbinsx,const Float_t *xbins
           ,Int_t nbinsy,const Float_t *ybins
           ,Int_t nbinsz,const Float_t *zbins)
           :TH3(name,title,nbinsx,xbins,nbinsy,ybins,nbinsz,zbins)
{
   //*-*-*-*-*-*-*-*Normal constructor for variable bin size 3-D histograms*-*-*-*
   //*-*            =======================================================
   TArrayF::Set(fNcells);
   if (fgDefaultSumw2) Sumw2();
}

//______________________________________________________________________________
TH3F::TH3F(const char *name,const char *title,Int_t nbinsx,const Double_t *xbins
           ,Int_t nbinsy,const Double_t *ybins
           ,Int_t nbinsz,const Double_t *zbins)
           :TH3(name,title,nbinsx,xbins,nbinsy,ybins,nbinsz,zbins)
{
   //*-*-*-*-*-*-*-*Normal constructor for variable bin size 3-D histograms*-*-*-*
   //*-*            =======================================================
   TArrayF::Set(fNcells);
   if (fgDefaultSumw2) Sumw2();
}

//______________________________________________________________________________
TH3F::TH3F(const TH3F &h3f) : TH3(), TArrayF()
{
   // Copy constructor.

   ((TH3F&)h3f).Copy(*this);
}

//______________________________________________________________________________
void TH3F::Copy(TObject &newth3) const
{
   //*-*-*-*-*-*-*Copy this 3-D histogram structure to newth3*-*-*-*-*-*-*-*-*-*
   //*-*          ===========================================

   TH3::Copy((TH3F&)newth3);
}

//______________________________________________________________________________
TH1 *TH3F::DrawCopy(Option_t *option) const
{
   // Draw copy.

   TString opt = option;
   opt.ToLower();
   if (gPad && !opt.Contains("same")) gPad->Clear();
   TH3F *newth3 = (TH3F*)Clone();
   newth3->SetDirectory(0);
   newth3->SetBit(kCanDelete);
   newth3->AppendPad(option);
   return newth3;
}

//______________________________________________________________________________
Double_t TH3F::GetBinContent(Int_t bin) const
{
   // Get bin content.

   if (fBuffer) ((TH3F*)this)->BufferEmpty();
   if (bin < 0) bin = 0;
   if (bin >= fNcells) bin = fNcells-1;
   if (!fArray) return 0;
   return Double_t (fArray[bin]);
}

//______________________________________________________________________________
void TH3F::Reset(Option_t *option)
{
   //*-*-*-*-*-*-*-*Reset this histogram: contents, errors, etc*-*-*-*-*-*-*-*
   //*-*            ===========================================

   TH3::Reset(option);
   TArrayF::Reset();
   // should also reset statistics once statistics are implemented for TH3
}

//______________________________________________________________________________
void TH3F::SetBinContent(Int_t bin, Double_t content)
{
   // Set bin content
   if (bin < 0) return;
   if (bin >= fNcells) return;
   fArray[bin] = Float_t (content);
   fEntries++;
   fTsumw = 0;
}

//______________________________________________________________________________
void TH3F::SetBinsLength(Int_t n)
{
   // Set total number of bins including under/overflow
   // Reallocate bin contents array

   if (n < 0) n = (fXaxis.GetNbins()+2)*(fYaxis.GetNbins()+2)*(fZaxis.GetNbins()+2);
   fNcells = n;
   TArrayF::Set(n);
}

//______________________________________________________________________________
void TH3F::Streamer(TBuffer &R__b)
{
   // Stream an object of class TH3F.

   if (R__b.IsReading()) {
      UInt_t R__s, R__c;
      if (R__b.GetParent() && R__b.GetVersionOwner() < 22300) return;
      Version_t R__v = R__b.ReadVersion(&R__s, &R__c);
      if (R__v > 2) {
         R__b.ReadClassBuffer(TH3F::Class(), this, R__v, R__s, R__c);
         return;
      }
      //====process old versions before automatic schema evolution
      if (R__v < 2) {
         R__b.ReadVersion();
         TH1::Streamer(R__b);
         TArrayF::Streamer(R__b);
         R__b.ReadVersion(&R__s, &R__c);
         TAtt3D::Streamer(R__b);
      } else {
         TH3::Streamer(R__b);
         TArrayF::Streamer(R__b);
         R__b.CheckByteCount(R__s, R__c, TH3F::IsA());
      }
      //====end of old versions

   } else {
      R__b.WriteClassBuffer(TH3F::Class(),this);
   }
}

//______________________________________________________________________________
TH3F& TH3F::operator=(const TH3F &h1)
{
   // Operator =

   if (this != &h1)  ((TH3F&)h1).Copy(*this);
   return *this;
}

//______________________________________________________________________________
TH3F operator*(Float_t c1, TH3F &h1)
{
   // Operator *

   TH3F hnew = h1;
   hnew.Scale(c1);
   hnew.SetDirectory(0);
   return hnew;
}

//______________________________________________________________________________
TH3F operator+(TH3F &h1, TH3F &h2)
{
   // Operator +

   TH3F hnew = h1;
   hnew.Add(&h2,1);
   hnew.SetDirectory(0);
   return hnew;
}

//______________________________________________________________________________
TH3F operator-(TH3F &h1, TH3F &h2)
{
   // Operator -

   TH3F hnew = h1;
   hnew.Add(&h2,-1);
   hnew.SetDirectory(0);
   return hnew;
}

//______________________________________________________________________________
TH3F operator*(TH3F &h1, TH3F &h2)
{
   // Operator *

   TH3F hnew = h1;
   hnew.Multiply(&h2);
   hnew.SetDirectory(0);
   return hnew;
}

//______________________________________________________________________________
TH3F operator/(TH3F &h1, TH3F &h2)
{
   // Operator /

   TH3F hnew = h1;
   hnew.Divide(&h2);
   hnew.SetDirectory(0);
   return hnew;
}


//______________________________________________________________________________
//                     TH3D methods
//  TH3D a 3-D histogram with eight bytes per cell (double)
//______________________________________________________________________________

ClassImp(TH3D)

//______________________________________________________________________________
TH3D::TH3D(): TH3(), TArrayD(1)
{
   // Constructor.
}

//______________________________________________________________________________
TH3D::~TH3D()
{
   // Destructor.
}

//______________________________________________________________________________
TH3D::TH3D(const char *name,const char *title,Int_t nbinsx,Double_t xlow,Double_t xup
           ,Int_t nbinsy,Double_t ylow,Double_t yup
           ,Int_t nbinsz,Double_t zlow,Double_t zup)
           :TH3(name,title,nbinsx,xlow,xup,nbinsy,ylow,yup,nbinsz,zlow,zup)
{
   //*-*-*-*-*-*-*-*-*Normal constructor for fix bin size 3-D histograms*-*-*-*-*
   //*-*              ==================================================
   TArrayD::Set(fNcells);
   if (fgDefaultSumw2) Sumw2();

   //if (xlow >= xup || ylow >= yup || zlow >= zup) SetBuffer(fgBufferSize);
}

//______________________________________________________________________________
TH3D::TH3D(const char *name,const char *title,Int_t nbinsx,const Float_t *xbins
           ,Int_t nbinsy,const Float_t *ybins
           ,Int_t nbinsz,const Float_t *zbins)
           :TH3(name,title,nbinsx,xbins,nbinsy,ybins,nbinsz,zbins)
{
   //*-*-*-*-*-*-*-*Normal constructor for variable bin size 3-D histograms*-*-*-*
   //*-*            =======================================================
   TArrayD::Set(fNcells);
   if (fgDefaultSumw2) Sumw2();
}

//______________________________________________________________________________
TH3D::TH3D(const char *name,const char *title,Int_t nbinsx,const Double_t *xbins
           ,Int_t nbinsy,const Double_t *ybins
           ,Int_t nbinsz,const Double_t *zbins)
           :TH3(name,title,nbinsx,xbins,nbinsy,ybins,nbinsz,zbins)
{
   //*-*-*-*-*-*-*-*Normal constructor for variable bin size 3-D histograms*-*-*-*
   //*-*            =======================================================
   TArrayD::Set(fNcells);
   if (fgDefaultSumw2) Sumw2();
}

//______________________________________________________________________________
TH3D::TH3D(const TH3D &h3d) : TH3(), TArrayD()
{
   // Copy constructor.

   ((TH3D&)h3d).Copy(*this);
}

//______________________________________________________________________________
void TH3D::Copy(TObject &newth3) const
{
   //*-*-*-*-*-*-*Copy this 3-D histogram structure to newth3*-*-*-*-*-*-*-*-*-*
   //*-*          ===========================================

   TH3::Copy((TH3D&)newth3);
}

//______________________________________________________________________________
TH1 *TH3D::DrawCopy(Option_t *option) const
{
   // Draw copy.

   TString opt = option;
   opt.ToLower();
   if (gPad && !opt.Contains("same")) gPad->Clear();
   TH3D *newth3 = (TH3D*)Clone();
   newth3->SetDirectory(0);
   newth3->SetBit(kCanDelete);
   newth3->AppendPad(option);
   return newth3;
}

//______________________________________________________________________________
Double_t TH3D::GetBinContent(Int_t bin) const
{
   // Get bin content.

   if (fBuffer) ((TH3D*)this)->BufferEmpty();
   if (bin < 0) bin = 0;
   if (bin >= fNcells) bin = fNcells-1;
   if (!fArray) return 0;
   return Double_t (fArray[bin]);
}

//______________________________________________________________________________
void TH3D::Reset(Option_t *option)
{
   //*-*-*-*-*-*-*-*Reset this histogram: contents, errors, etc*-*-*-*-*-*-*-*
   //*-*            ===========================================

   TH3::Reset(option);
   TArrayD::Reset();
   // should also reset statistics once statistics are implemented for TH3
}

//______________________________________________________________________________
void TH3D::SetBinContent(Int_t bin, Double_t content)
{
   // Set bin content
   if (bin < 0) return;
   if (bin >= fNcells) return;
   fArray[bin] = Double_t (content);
   fEntries++;
   fTsumw = 0;
}


//______________________________________________________________________________
void TH3D::SetBinsLength(Int_t n)
{
   // Set total number of bins including under/overflow
   // Reallocate bin contents array

   if (n < 0) n = (fXaxis.GetNbins()+2)*(fYaxis.GetNbins()+2)*(fZaxis.GetNbins()+2);
   fNcells = n;
   TArrayD::Set(n);
}

//______________________________________________________________________________
void TH3D::Streamer(TBuffer &R__b)
{
   // Stream an object of class TH3D.

   if (R__b.IsReading()) {
      UInt_t R__s, R__c;
      if (R__b.GetParent() && R__b.GetVersionOwner() < 22300) return;
      Version_t R__v = R__b.ReadVersion(&R__s, &R__c);
      if (R__v > 2) {
         R__b.ReadClassBuffer(TH3D::Class(), this, R__v, R__s, R__c);
         return;
      }
      //====process old versions before automatic schema evolution
      if (R__v < 2) {
         R__b.ReadVersion();
         TH1::Streamer(R__b);
         TArrayD::Streamer(R__b);
         R__b.ReadVersion(&R__s, &R__c);
         TAtt3D::Streamer(R__b);
      } else {
         TH3::Streamer(R__b);
         TArrayD::Streamer(R__b);
         R__b.CheckByteCount(R__s, R__c, TH3D::IsA());
      }
      //====end of old versions

   } else {
      R__b.WriteClassBuffer(TH3D::Class(),this);
   }
}

//______________________________________________________________________________
TH3D& TH3D::operator=(const TH3D &h1)
{
   // Operator =

   if (this != &h1)  ((TH3D&)h1).Copy(*this);
   return *this;
}

//______________________________________________________________________________
TH3D operator*(Float_t c1, TH3D &h1)
{
   // Operator *

   TH3D hnew = h1;
   hnew.Scale(c1);
   hnew.SetDirectory(0);
   return hnew;
}

//______________________________________________________________________________
TH3D operator+(TH3D &h1, TH3D &h2)
{
   // Operator +

   TH3D hnew = h1;
   hnew.Add(&h2,1);
   hnew.SetDirectory(0);
   return hnew;
}

//______________________________________________________________________________
TH3D operator-(TH3D &h1, TH3D &h2)
{
   // Operator -

   TH3D hnew = h1;
   hnew.Add(&h2,-1);
   hnew.SetDirectory(0);
   return hnew;
}

//______________________________________________________________________________
TH3D operator*(TH3D &h1, TH3D &h2)
{
   // Operator *

   TH3D hnew = h1;
   hnew.Multiply(&h2);
   hnew.SetDirectory(0);
   return hnew;
}

//______________________________________________________________________________
TH3D operator/(TH3D &h1, TH3D &h2)
{
   // Operator /

   TH3D hnew = h1;
   hnew.Divide(&h2);
   hnew.SetDirectory(0);
   return hnew;
}