Int_t binning(Int_t, Int_t, 
	      Int_t, Int_t,
	      Float_t *, Float_t *);

Int_t binning(Int_t xNumBins, Int_t xfixed, 
	      Int_t zNumBins, Int_t zfixed,
	      Float_t * xEdges, Float_t * zEdges)
{
  Float_t xMax=0.6;
  Float_t xMin=0.02;
  Float_t zMax=0.75;
  Float_t zMin=0.25;

  if( xfixed)
    {
      xEdges[0]=0.02;
      xEdges[1]=0.04;
      xEdges[2]=0.08;
      xEdges[3]=0.12;
      xEdges[4]=0.16;
      xEdges[5]=0.25;
      xEdges[6]=0.4;
      xEdges[7]=0.6;
    }
  else
    {
      for(Int_t ix=0; ix <= xNumBins+1; ix++)
	{
	  xEdges[ix]=xMin + ix * (xMax-xMin)/xNumBins ;
	}  
    }

  if( zfixed )
    zNumBins=1;

  if( zfixed )
    {
      zEdges[0]=0.2;
      zEdges[1]=0.8;
    }
  else
    {
      for(Int_t iz=0; iz < zNumBins+1; iz++)
	{
	  zEdges[iz]=zMin + iz * (zMax-zMin)/zNumBins ;
	}  
    }

  return 1;
}