PlotGraph2D: PlotGraph2D

In DataVisualizations: Visualizations of High-Dimensional Data

PlotGraph2D

Description

plots a neighborhood graph in two dimensions given the 2D coordinates of the points

Usage

PlotGraph2D(AdjacencyMatrix, Points, Cls, Colors, xlab = "X", ylab = "Y", xlim,
ylim, Plotter = "native", LineColor = "grey", pch, lwd, main = "",
mainSize,SampleSize=NULL)

Arguments

AdjacencyMatrix	[1:n,1:n] numerical matrix consting of binary values. 1 indicates that two points have an edge, zero that they do not
Points	[1:n,1:2] numeric matrix of two feature
Cls	[1:n] numeric vector of k classes, if not set per default every point is in first class
Colors	Optional, string defining the k colors, one per class
xlab	Optional, string for xlabel
ylab	Optional, string for ylabel
xlim	Optional, [1:2] vector of x-axis limits
ylim	Optional, [1:2] vector of y-axis limits
Plotter	Optional, either "native" or "plotly"
LineColor	Optional, color of edges
pch	Optional, for Plotter="native" shape of point, usally can be in a range from zero to 25, see pch of plot for details; for Plotter="Plotly" the size of point
lwd	width of the lines
main	Optional, string for the title of plot
mainSize	Optional, scalar for the size of the title of plot
SampleSize	Optional, scalar for the size of sample of vertices that will be plotted

Details

The points are the vertices of the graph. the adjacency matrix defines the edges. Via adjacency matrix various graphs, like from deldir package, can be used.

Sometimes the amount of vertices is high in which take plotting take very long. For such a case use SampleSize.

Value

native plot or plotly object depending on input argument Plotter

Author(s)

Michael Thrun

References

Lecture of Knowledge Discovery II

See Also

pch

Examples

N=10
x=runif(N)
y=runif(N)
Euklid=as.matrix(dist(cbind(x,y)))
Radius=quantile(as.vector(Euklid),0.5)
RKugelGraphAdjMatrix = matrix(0, ncol = N, nrow = N)
for (i in 1:N) {
  RInd = which(Euklid[i, ] <= Radius, arr.ind = TRUE)
  RKugelGraphAdjMatrix[i, RInd] = 1
}
PlotGraph2D(RKugelGraphAdjMatrix,cbind(x,y))

DataVisualizations documentation built on Aug. 25, 2025, 1:12 a.m.