pcds (version 0.1.2)

Gam2PEbastri: The indicator for two points being a dominating set for Proportional Edge Proximity Catch Digraphs (PE-PCDs) - basic triangle case

Description

Returns \(I(\){pt1,pt2} is a dominating set of the PE-PCD\()\) where the vertices of the PE-PCD are the 2D data set Dt in the basic triangle \(T_b=T((0,0),(1,0),(c_1,c_2))\), that is, returns 1 if {pt1,pt2} is a dominating set of PE-PCD, returns 0 otherwise.

PE proximity regions are defined with respect to \(T_b\). In the basic triangle, \(T_b\), \(c_1\) is in \([0,1/2]\), \(c_2>0\) and \((1-c_1)^2+c_2^2 \le 1\).

Any given triangle can be mapped to the basic triangle by a combination of rigid body motions (i.e., translation, rotation and reflection) and scaling, preserving uniformity of the points in the original triangle. Hence basic triangle is useful for simulation studies under the uniformity hypothesis.

Vertex regions are based on center \(M=(m_1,m_2)\) in Cartesian coordinates or \(M=(\alpha,\beta,\gamma)\) in barycentric coordinates in the interior of a basic triangle \(T_b\); default is \(M=(1,1,1)\) i.e., the center of mass of \(T_b\). Point, pt1, is in the vertex region of vertex rv1 (default is NULL); and point, pt2, is in the vertex region of vertex rv2 (default is NULL); vertices are labeled as \(1,2,3\) in the order they are stacked row-wise.

ch.data.pnts is for checking whether points pt1 and pt2 are both data points in Dt or not (default is FALSE), so by default this function checks whether the points pt1 and pt2 would constitute a dominating set if they both were actually in the data set.

See also (ceyhan:Phd-thesis,ceyhan:dom-num-NPE-Spat2011;textualpcds).

Usage

Gam2PEbastri(
  pt1,
  pt2,
  Dt,
  r,
  c1,
  c2,
  M = c(1, 1, 1),
  rv1 = NULL,
  rv2 = NULL,
  ch.data.pnts = FALSE
)

Arguments

pt1, pt2

Two 2D points to be tested for constituting a dominating set of the PE-PCD.

Dt

A set of 2D points which constitutes the vertices of the PE-PCD.

r

A positive real number which serves as the expansion parameter in PE proximity region; must be \(\ge 1\).

c1, c2

Positive real numbers which constitute the vertex of the basic triangle. adjacent to the shorter edges; \(c_1\) must be in \([0,1/2]\), \(c_2>0\) and \((1-c_1)^2+c_2^2 \le 1\).

M

A 2D point in Cartesian coordinates or a 3D point in barycentric coordinates which serves as a center in the interior of the basic triangle \(T_b\) or the circumcenter of \(T_b\); default is \(M=(1,1,1)\) i.e., the center of mass of \(T_b\).

rv1, rv2

The indices of the vertices whose regions contains pt1 and pt2, respectively. They take the vertex labels as \(1,2,3\) as in the row order of the vertices in \(T_b\) (default is NULL for both).

ch.data.pnts

A logical argument for checking whether points pt1 and pt2 are data points in Dt or not (default is FALSE).

Value

\(I(\){pt1,pt2} is a dominating set of the PE-PCD\()\) where the vertices of the PE-PCD are the 2D data set Dt), that is, returns 1 if {pt1,pt2} is a dominating set of PE-PCD, returns 0 otherwise

References

See Also

Gam2PEtri, Gam2ASbastri, and Gam2AStri

Examples

# NOT RUN {
c1<-.4; c2<-.6;
A<-c(0,0); B<-c(1,0); C<-c(c1,c2);
Tb<-rbind(A,B,C)
n<-10  #try also n<-20

set.seed(1)
dat<-runif.bastri(n,c1,c2)$g

M<-as.numeric(runif.bastri(1,c1,c2)$g)  #try also M<-c(.6,.3)

r<-2

Gam2PEbastri(dat[1,],dat[2,],dat,r,c1,c2,M)
Gam2PEbastri(c(1,1),dat[2,],dat,r,c1,c2,M)

Gam2PEbastri(c(1,2),dat[2,],dat,r,c1,c2,M)

Gam2PEbastri(c(1,2),c(1,3),rbind(c(1,2),c(1,3)),r,c1,c2,M)
Gam2PEbastri(c(1,2),c(1,3),rbind(c(1,2),c(1,3)),r,c1,c2,M,ch.data.pnts = TRUE)

ind.gam2<-vector()
for (i in 1:(n-1))
  for (j in (i+1):n)
  {if (Gam2PEbastri(dat[i,],dat[j,],dat,r,c1,c2,M)==1)
   ind.gam2<-rbind(ind.gam2,c(i,j))}
ind.gam2

#or try
rv1<-rv.bastri.cent(dat[1,],c1,c2,M)$rv;
rv2<-rv.bastri.cent(dat[2,],c1,c2,M)$rv;
Gam2PEbastri(dat[1,],dat[2,],dat,r,c1,c2,M,rv1,rv2)

#or try
rv1<-rv.bastri.cent(dat[1,],c1,c2,M)$rv;
Gam2PEbastri(dat[1,],dat[2,],dat,r,c1,c2,M,rv1)

#or try
rv2<-rv.bastri.cent(dat[2,],c1,c2,M)$rv;
Gam2PEbastri(dat[1,],dat[2,],dat,r,c1,c2,M,rv2=rv2)

P1<-c(.4,.2)
P2<-c(.6,.2)
Gam2PEbastri(P1,P2,dat,r,c1,c2,M)

Gam2PEbastri(P1,P2,rbind(dat,dat),r,c1,c2,M)

dat.fr<-data.frame(a=dat)
Gam2PEbastri(P1,P2,dat.fr,r,c1,c2,M)

Gam2PEbastri(c(1,2),dat[2,],dat,r,c1,c2,M,ch.data.pnts = FALSE)
#gives an error message if ch.data.pnts = TRUE since not both points are data points in Dt

# }