 ROOT   Reference Guide ROOT::Math::Delaunay2D Class Reference

Class to generate a Delaunay triangulation of a 2D set of points.

Algorithm based on Triangle, a two-dimensional quality mesh generator and Delaunay triangulator from Jonathan Richard Shewchuk.

Definition at line 71 of file Delaunay2D.h.

struct  Triangle

## Public Types

typedef std::vector< TriangleTriangles

## Public Member Functions

Delaunay2D (int n, const double *x, const double *y, const double *z, double xmin=0, double xmax=0, double ymin=0, double ymax=0)
class constructor from array of data points More...

Triangles::const_iterator begin () const

Triangles::const_iterator end () const

void FindAllTriangles ()
Find all triangles. More...

double Interpolate (double x, double y)
Return the Interpolated z value corresponding to the (x,y) point. More...

Int_t NumberOfTriangles () const
return the number of triangles More...

void SetInputPoints (int n, const double *x, const double *y, const double *z, double xmin=0, double xmax=0, double ymin=0, double ymax=0)
set the input points for building the graph More...

void SetZOuterValue (double z=0.)
set z value to be returned for points outside the region More...

double XMax () const

double XMin () const

double YMax () const

double YMin () const

double ZOuterValue () const
return the user defined Z-outer value More...

## Protected Member Functions

unsigned int Cell (UInt_t x, UInt_t y) const
grid cells with containing triangles More...

int CellX (double x) const

int CellY (double y) const

## Protected Attributes

std::set< UInt_tfCells [(fNCells+1) *(fNCells+1)]
inverse denominator to calculate X cell = fNCells / (fYNmax - fYNmin) More...

Bool_t fInit
Height for points lying outside the convex hull. More...

Int_t fNdt

Int_t fNpoints
Number of Delaunay triangles found. More...

double fOffsetX
Maximum value of fYN. More...

double fOffsetY
Normalization offset X. More...

double fScaleFactorX
Normalization offset Y. More...

double fScaleFactorY
Normalization factor X. More...

Triangles fTriangles
True if FindAllTriangels() has been performed. More...

const double * fX
Number of data points. More...

double fXCellStep
number of cells to divide the normalized space More...

std::vector< double > fXN
Triangles of Triangulation. More...

double fXNmax
Minimum value of fXN. More...

double fXNmin
Pointer to Z array. More...

const double * fY
Pointer to X array (managed externally) More...

double fYCellStep
inverse denominator to calculate X cell = fNCells / (fXNmax - fXNmin) More...

std::vector< double > fYN
normalized X More...

double fYNmax
Minimum value of fYN. More...

double fYNmin
Maximum value of fXN. More...

const double * fZ
Pointer to Y array. More...

double fZout
Normalization factor Y. More...

## Static Protected Attributes

static const int fNCells = 25
normalized Y More...

## Private Member Functions

Delaunay2D (const Delaunay2D &)

void DoFindTriangles ()
internal function to find the triangle use Triangle or CGAL if flag is set
More...

double DoInterpolateNormalized (double x, double y)
internal method to compute the interpolation More...

void DoNormalizePoints ()
internal function to normalize the points More...

double Linear_transform (double x, double offset, double factor)

Delaunay2Doperator= (const Delaunay2D &)

#include <Math/Delaunay2D.h>

## ◆ Triangles

 typedef std::vector ROOT::Math::Delaunay2D::Triangles

Definition at line 85 of file Delaunay2D.h.

## ◆ Delaunay2D() [1/2]

 ROOT::Math::Delaunay2D::Delaunay2D ( int n, const double * x, const double * y, const double * z, double xmin = 0, double xmax = 0, double ymin = 0, double ymax = 0 )

class constructor from array of data points

Definition at line 34 of file Delaunay2D.cxx.

## ◆ Delaunay2D() [2/2]

 ROOT::Math::Delaunay2D::Delaunay2D ( const Delaunay2D & )
private

## ◆ begin()

 Triangles::const_iterator ROOT::Math::Delaunay2D::begin ( ) const
inline

Definition at line 116 of file Delaunay2D.h.

## ◆ Cell()

 unsigned int ROOT::Math::Delaunay2D::Cell ( UInt_t x, UInt_t y ) const
inlineprotected

grid cells with containing triangles

Definition at line 274 of file Delaunay2D.h.

## ◆ CellX()

 int ROOT::Math::Delaunay2D::CellX ( double x ) const
inlineprotected

Definition at line 278 of file Delaunay2D.h.

## ◆ CellY()

 int ROOT::Math::Delaunay2D::CellY ( double y ) const
inlineprotected

Definition at line 282 of file Delaunay2D.h.

## ◆ DoFindTriangles()

 void ROOT::Math::Delaunay2D::DoFindTriangles ( )
private

internal function to find the triangle use Triangle or CGAL if flag is set

Triangle implementation for finding all the triangles.

Definition at line 256 of file Delaunay2D.cxx.

## ◆ DoInterpolateNormalized()

 double ROOT::Math::Delaunay2D::DoInterpolateNormalized ( double x, double y )
private

internal method to compute the interpolation

Triangle implementation for interpolation 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.

Definition at line 379 of file Delaunay2D.cxx.

## ◆ DoNormalizePoints()

 void ROOT::Math::Delaunay2D::DoNormalizePoints ( )
private

internal function to normalize the points

Triangle implementation for normalizing the points.

Definition at line 244 of file Delaunay2D.cxx.

## ◆ end()

 Triangles::const_iterator ROOT::Math::Delaunay2D::end ( ) const
inline

Definition at line 117 of file Delaunay2D.h.

## ◆ FindAllTriangles()

 void ROOT::Math::Delaunay2D::FindAllTriangles ( )

Find all triangles.

Definition at line 128 of file Delaunay2D.cxx.

## ◆ Interpolate()

 double ROOT::Math::Delaunay2D::Interpolate ( double x, double y )

Return the Interpolated z value corresponding to the (x,y) point.

Definition at line 104 of file Delaunay2D.cxx.

## ◆ Linear_transform()

 double ROOT::Math::Delaunay2D::Linear_transform ( double x, double offset, double factor )
inlineprivate

Definition at line 125 of file Delaunay2D.h.

## ◆ NumberOfTriangles()

 Int_t ROOT::Math::Delaunay2D::NumberOfTriangles ( ) const
inline

return the number of triangles

Definition at line 102 of file Delaunay2D.h.

## ◆ operator=()

 Delaunay2D & ROOT::Math::Delaunay2D::operator= ( const Delaunay2D & )
private

## ◆ SetInputPoints()

 void ROOT::Math::Delaunay2D::SetInputPoints ( int n, const double * x, const double * y, const double * z, double xmin = 0, double xmax = 0, double ymin = 0, double ymax = 0 )

set the input points for building the graph

set the input points

Definition at line 59 of file Delaunay2D.cxx.

## ◆ SetZOuterValue()

 void ROOT::Math::Delaunay2D::SetZOuterValue ( double z = 0. )
inline

set z value to be returned for points outside the region

Definition at line 110 of file Delaunay2D.h.

## ◆ XMax()

 double ROOT::Math::Delaunay2D::XMax ( ) const
inline

Definition at line 105 of file Delaunay2D.h.

## ◆ XMin()

 double ROOT::Math::Delaunay2D::XMin ( ) const
inline

Definition at line 104 of file Delaunay2D.h.

## ◆ YMax()

 double ROOT::Math::Delaunay2D::YMax ( ) const
inline

Definition at line 107 of file Delaunay2D.h.

## ◆ YMin()

 double ROOT::Math::Delaunay2D::YMin ( ) const
inline

Definition at line 106 of file Delaunay2D.h.

## ◆ ZOuterValue()

 double ROOT::Math::Delaunay2D::ZOuterValue ( ) const
inline

return the user defined Z-outer value

Definition at line 113 of file Delaunay2D.h.

## ◆ fCells

 std::set ROOT::Math::Delaunay2D::fCells[(fNCells+1) *(fNCells+1)]
protected

inverse denominator to calculate X cell = fNCells / (fYNmax - fYNmin)

Definition at line 272 of file Delaunay2D.h.

## ◆ fInit

 Bool_t ROOT::Math::Delaunay2D::fInit
protected

Height for points lying outside the convex hull.

Definition at line 179 of file Delaunay2D.h.

## ◆ fNCells

 const int ROOT::Math::Delaunay2D::fNCells = 25
staticprotected

normalized Y

Definition at line 269 of file Delaunay2D.h.

## ◆ fNdt

 Int_t ROOT::Math::Delaunay2D::fNdt
protected

Definition at line 150 of file Delaunay2D.h.

## ◆ fNpoints

 Int_t ROOT::Math::Delaunay2D::fNpoints
protected

Number of Delaunay triangles found.

Definition at line 151 of file Delaunay2D.h.

## ◆ fOffsetX

 double ROOT::Math::Delaunay2D::fOffsetX
protected

Maximum value of fYN.

Definition at line 165 of file Delaunay2D.h.

## ◆ fOffsetY

 double ROOT::Math::Delaunay2D::fOffsetY
protected

Normalization offset X.

Definition at line 166 of file Delaunay2D.h.

## ◆ fScaleFactorX

 double ROOT::Math::Delaunay2D::fScaleFactorX
protected

Normalization offset Y.

Definition at line 168 of file Delaunay2D.h.

## ◆ fScaleFactorY

 double ROOT::Math::Delaunay2D::fScaleFactorY
protected

Normalization factor X.

Definition at line 169 of file Delaunay2D.h.

## ◆ fTriangles

 Triangles ROOT::Math::Delaunay2D::fTriangles
protected

True if FindAllTriangels() has been performed.

Definition at line 183 of file Delaunay2D.h.

## ◆ fX

 const double* ROOT::Math::Delaunay2D::fX
protected

Number of data points.

Definition at line 153 of file Delaunay2D.h.

## ◆ fXCellStep

 double ROOT::Math::Delaunay2D::fXCellStep
protected

number of cells to divide the normalized space

Definition at line 270 of file Delaunay2D.h.

## ◆ fXN

 std::vector ROOT::Math::Delaunay2D::fXN
protected

Triangles of Triangulation.

Definition at line 261 of file Delaunay2D.h.

## ◆ fXNmax

 double ROOT::Math::Delaunay2D::fXNmax
protected

Minimum value of fXN.

Definition at line 158 of file Delaunay2D.h.

## ◆ fXNmin

 double ROOT::Math::Delaunay2D::fXNmin
protected

Pointer to Z array.

Definition at line 157 of file Delaunay2D.h.

## ◆ fY

 const double* ROOT::Math::Delaunay2D::fY
protected

Pointer to X array (managed externally)

Definition at line 154 of file Delaunay2D.h.

## ◆ fYCellStep

 double ROOT::Math::Delaunay2D::fYCellStep
protected

inverse denominator to calculate X cell = fNCells / (fXNmax - fXNmin)

Definition at line 271 of file Delaunay2D.h.

## ◆ fYN

 std::vector ROOT::Math::Delaunay2D::fYN
protected

normalized X

Definition at line 262 of file Delaunay2D.h.

## ◆ fYNmax

 double ROOT::Math::Delaunay2D::fYNmax
protected

Minimum value of fYN.

Definition at line 160 of file Delaunay2D.h.

## ◆ fYNmin

 double ROOT::Math::Delaunay2D::fYNmin
protected

Maximum value of fXN.

Definition at line 159 of file Delaunay2D.h.

## ◆ fZ

 const double* ROOT::Math::Delaunay2D::fZ
protected

Pointer to Y array.

Definition at line 155 of file Delaunay2D.h.

## ◆ fZout

 double ROOT::Math::Delaunay2D::fZout
protected

Normalization factor Y.

Definition at line 171 of file Delaunay2D.h.

Libraries for ROOT::Math::Delaunay2D: [legend]

The documentation for this class was generated from the following files: