TGraphDelaunay

class TGraphDelaunay : public TNamed

    protected:

          void CreateTrianglesDataStructure()
        Bool_t Enclose(Int_t T1, Int_t T2, Int_t T3, Int_t Ex) const
          void FileIt(Int_t P, Int_t N, Int_t M)
          void FindHull()
        Bool_t InHull(Int_t E, Int_t X) const
      Double_t InterpolateOnPlane(Int_t TI1, Int_t TI2, Int_t TI3, Int_t E) const

    public:

                      TGraphDelaunay()
                      TGraphDelaunay(TGraph2D* g)
                      TGraphDelaunay(const TGraphDelaunay&)
              virtual ~TGraphDelaunay()
       static TClass* Class()
             Double_t ComputeZ(Double_t x, Double_t y)
                 void FindAllTriangles()
            TGraph2D* GetGraph2D() const
             Double_t GetMarginBinsContent() const
               Int_t* GetMTried() const
                Int_t GetNdt() const
               Int_t* GetNTried() const
               Int_t* GetPTried() const
            Double_t* GetXN() const
             Double_t GetXNmax() const
             Double_t GetXNmin() const
            Double_t* GetYN() const
             Double_t GetYNmax() const
             Double_t GetYNmin() const
             Double_t Interpolate(Double_t x, Double_t y)
      virtual TClass* IsA() const
      TGraphDelaunay& operator=(const TGraphDelaunay&)
                 void SetMarginBinsContent(Double_t z = 0.)
                 void SetMaxIter(Int_t n = 100000)
         virtual void ShowMembers(TMemberInspector& insp, char* parent)
         virtual void Streamer(TBuffer& b)
                 void StreamerNVirtual(TBuffer& b)

Data Members

    protected:

          Int_t fNdt          !Number of Delaunay triangles found
          Int_t fNpoints      !Number of data points in fGraph2D
          Int_t fNhull        !Number of points in the hull
      Double_t* fX            !Pointer to fGraph2D->fX
      Double_t* fY            !Pointer to fGraph2D->fY
      Double_t* fZ            !Pointer to fGraph2D->fZ
      Double_t* fXN           !fGraph2D vectors normalized of size fNpoints
      Double_t* fYN           !fGraph2D vectors normalized of size fNpoints
       Double_t fXNmin        !Minimum value of fXN
       Double_t fXNmax        !Maximum value of fXN
       Double_t fYNmin        !Minimum value of fYN
       Double_t fYNmax        !Maximum value of fYN
       Double_t fXoffset      !
       Double_t fYoffset      !Parameters used to normalize user data
       Double_t fScaleFactor  !
       Double_t fZout         !Histogram bin height for points lying outside the convex hull
      Double_t* fDist         !Array used to order mass points by distance
          Int_t fMaxIter      !Maximum number of iterations to find Delaunay triangles
          Int_t fTriedSize    !Real size of the fxTried arrays
         Int_t* fPTried       !
         Int_t* fNTried       !Delaunay triangles storage of size fNdt
         Int_t* fMTried       !
         Int_t* fHullPoints   !Hull points of size fNhull
         Int_t* fOrder        !Array used to order mass points by distance
         Bool_t fAllTri       !True if FindAllTriangles() has been performed on fGraph2D
      TGraph2D* fGraph2D      !2D graph containing the user data

Class Description

 TGraphDelaunay generates a Delaunay triangulation of a TGraph2D. This
 triangulation code derives from an implementation done by Luke Jones
 (Royal Holloway, University of London) in April 2002 in the PAW context.

 This software cannot be guaranteed to work under all circumstances. They
 were originally written to work with a few hundred points in an XY space
 with similar X and Y ranges.

 Definition of Delaunay triangulation (After B. Delaunay):
 For a set S of points in the Euclidean plane, the unique triangulation DT(S)
 of S such that no point in S is inside the circumcircle of any triangle in
 DT(S). DT(S) is the dual of the Voronoi diagram of S. If n is the number of
 points in S, the Voronoi diagram of S is the partitioning of the plane
 containing S points into n convex polygons such that each polygon contains
 exactly one point and every point in a given polygon is closer to its
 central point than to any other. A Voronoi diagram is sometimes also known
 as a Dirichlet tessellation.

 TGraphDelaunay default constructor

 TGraphDelaunay default constructor

 TGraphDelaunay destructor.

 Return the z value corresponding to the (x,y) point in fGraph2D

 Fonction used internally only. It creates the data structures needed to
 compute the Delaunay triangles.

 Is point E inside the triangle T1-T2-T3 ?

 Files the triangle defined by the 3 vertices P, N and M into the
 fxTried arrays. If these arrays are to small they are automatically
 expanded.

 Attempt to find all the Delaunay triangles of the point set. It is not
 guaranteed that it will fully succeed, and no check is made that it has
 fully succeeded (such a check would be possible by referencing the points
 that make up the convex hull). The method is to check if each triangle
 shares all three of its sides with other triangles. If not, a point is
 generated just outside the triangle on the side(s) not shared, and a new
 triangle is found for that point. If this method is not working properly
 (many triangles are not being found) it's probably because the new points
 are too far beyond or too close to the non-shared sides. Fiddling with
 the size of the `alittlebit' parameter may help.

 Finds those points which make up the convex hull of the set. If the xy
 plane were a sheet of wood, and the points were nails hammered into it
 at the respective coordinates, then if an elastic band were stretched
 over all the nails it would form the shape of the convex hull. Those
 nails in contact with it are the points that make up the hull.

 Is point E inside the hull defined by all points apart from X ?

 Finds the z-value at point E given that it lies
 on the plane defined by T1,T2,T3

 Finds the Delaunay triangle that the point (xi,yi) sits in (if any) and
 calculate a z-value for it by linearly interpolating the z-values that
 make up that triangle.

 Defines the number of triangles tested for a Delaunay triangle
 (number of iterations) before abandoning the search

 Sets the histogram bin height for points lying outside the convex hull ie:
 the bins in the margin.

Inline Functions

              TGraph2D* GetGraph2D() const
               Double_t GetMarginBinsContent() const
                  Int_t GetNdt() const
                 Int_t* GetPTried() const
                 Int_t* GetNTried() const
                 Int_t* GetMTried() const
              Double_t* GetXN() const
              Double_t* GetYN() const
               Double_t GetXNmin() const
               Double_t GetXNmax() const
               Double_t GetYNmin() const
               Double_t GetYNmax() const
                TClass* Class()
                TClass* IsA() const
                   void ShowMembers(TMemberInspector& insp, char* parent)
                   void Streamer(TBuffer& b)
                   void StreamerNVirtual(TBuffer& b)
         TGraphDelaunay TGraphDelaunay(const TGraphDelaunay&)
        TGraphDelaunay& operator=(const TGraphDelaunay&)