Class DiscreteFrechetDistance

The Fréchet distance is a measure of similarity between curves. Thus, it can be used like the Hausdorff distance.

An analogy for the Fréchet distance taken from Computing Discrete Fréchet Distance:

A man is walking a dog on a leash: the man can move
on one curve, the dog on the other; both may vary their
speed, but backtracking is not allowed.

Inheritance

object

DiscreteFrechetDistance

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Namespace: NetTopologySuite.Algorithm.Distance

Assembly: NetTopologySuite.dll

Syntax

public class DiscreteFrechetDistance

Remarks

Its metric is better than the Hausdorff distance because it takes the directions of the curves into account. It is possible that two curves have a small Hausdorff but a large Fréchet distance.

This implementation is based on the following optimized Fréchet distance algorithm:

Thomas Devogele, Maxence Esnault, Laurent Etienne. Distance discrète de Fréchet optimisée. Spatial
Analysis and Geomatics (SAGEO), Nov 2016, Nice, France. hal-02110055

Several matrix storage implementations are provided

Additional information:

• Fréchet distance
• Computing Discrete Fréchet Distance
• Distance discrète de Fréchet optimisée
• Fast Discrete Fréchet Distance

Constructors

DiscreteFrechetDistance(Geometry, Geometry)

Creates an instance of this class using the provided geometries.

Declaration

public DiscreteFrechetDistance(Geometry g0, Geometry g1)

Parameters

Type	Name	Description
Geometry	g0	A geometry
Geometry	g1	A geometry

Properties

Coordinates

Gets the pair of Coordinates at which the distance is obtained.

Declaration

public Coordinate[] Coordinates { get; }

Property Value

Type	Description
Coordinate[]	The pair of Coordinates at which the distance is obtained

Methods

Distance(Geometry, Geometry)

Computes the Discrete Fréchet Distance between two Geometrys using a cartesian distance computation function.

Declaration

public static double Distance(Geometry g0, Geometry g1)

Parameters

Type	Name	Description
Geometry	g0	The 1st geometry
Geometry	g1	The 2nd geometry

Returns

Type	Description
double	The cartesian distance between g0 and g1