pcds (version 0.1.4)

plotASarcsMT: The plot of the arcs of Arc Slice Proximity Catch Digraph (AS-PCD) for a 2D data set - multiple triangle case

Description

Plots the arcs of AS-PCD whose vertices are the data points in Xp and Delaunay triangles based on Yp points.

AS proximity regions are constructed with respect to the Delaunay triangles based on Yp points, i.e., AS proximity regions are defined only for Xp points inside the convex hull of Yp points. That is, arcs may exist for Xp points only inside the convex hull of Yp points.

Vertex regions are based on the center M="CC" for circumcenter of each Delaunay triangle or \(M=(\alpha,\beta,\gamma)\) in barycentric coordinates in the interior of each Delaunay triangle; default is M="CC" i.e., circumcenter of each triangle.

See (ceyhan:Phd-thesis,ceyhan:comp-geo-2010,ceyhan:mcap2012;textualpcds) for more on AS-PCDs. Also see (okabe:2000,ceyhan:comp-geo-2010,sinclair:2016;textualpcds) for more on Delaunay triangulation and the corresponding algorithm.

Usage

plotASarcsMT(
  Xp,
  Yp,
  M = "CC",
  asp = NA,
  main = "",
  xlab = "",
  ylab = "",
  xlim = NULL,
  ylim = NULL,
  ...
)

Value

A plot of the arcs of the AS-PCD for a 2D data set Xp where AS proximity regions are defined with respect to the Delaunay triangles based on Yp points; also plots the Delaunay triangles based on Yp points.

Arguments

Xp

A set of 2D points which constitute the vertices of the AS-PCD.

Yp

A set of 2D points which constitute the vertices of the Delaunay triangulation. The Delaunay triangles partition the convex hull of Yp points.

M

The center of the triangle. "CC" stands for circumcenter of each Delaunay triangle tri or 3D point in barycentric coordinates which serves as a center in the interior of each Delaunay triangle; default is M="CC" i.e., the circumcenter of each triangle.

asp

A numeric value, giving the aspect ratio for \(y\) axis to \(x\)-axis \(y/x\) (default is NA), see the official help page for asp by typing "? asp".

main

An overall title for the plot (default="").

xlab, ylab

Titles for the \(x\) and \(y\) axes, respectively (default="" for both).

xlim, ylim

Two numeric vectors of length 2, giving the \(x\)- and \(y\)-coordinate ranges (default=NULL for both).

...

Additional plot parameters.

Author

Elvan Ceyhan

References

See Also

plotASarcsTri, plotPEarcsTri, plotPEarcsMT, plotCSarcsTri, and plotCSarcsMT

Examples

#nx is number of X points (target) and ny is number of Y points (nontarget)
nx<-20; ny<-4;  #try also nx<-40; ny<-10 or nx<-1000; ny<-10;

set.seed(1)
Xp<-cbind(runif(nx,0,1),runif(nx,0,1))
Yp<-cbind(runif(ny,0,1),runif(ny,0,1))

M<-c(1,1,1)  #try also M<-c(1,2,3)

plotASarcsMT(Xp,Yp,M,xlab="",ylab="")
plotASarcsMT(Xp,Yp,M,asp=1,xlab="",ylab="")

plotASarcsMT(Xp,Yp[1:3,],M,xlab="",ylab="")

Xlim<-range(Xp[,1],Yp[,1])
Ylim<-range(Xp[,2],Yp[,2])
xd<-Xlim[2]-Xlim[1]
yd<-Ylim[2]-Ylim[1]

plotASarcsMT(Xp,Yp,M,xlab="",ylab="",xlim=Xlim+xd*c(-.01,.01),ylim=Ylim+yd*c(-.01,.01))
plotASarcsMT(Xp,Yp,M,asp=1,xlab="",ylab="",xlim=Xlim+xd*c(-.01,.01),ylim=Ylim+yd*c(-.01,.01))