orderPoints: Order Points Clockwise or Counter-Clockwise

In contoureR: Contouring of Non-Regular Three-Dimensional Data

Description

Returns the indexes of supplied points, x and y, ordered either clockwise or anticlockwise about another point, which by default is taken to be the non-weighted midpoint of the supplied data

Usage

orderPoints(x, y, ..., xm = mean(range(x)), ym = mean(range(y)),
  clockwise = TRUE)

Arguments

x	numeric vector of x values
y	numeric vector of y values of same length as x
...	not used
xm	the x value of the reference point
ym	the y value of the reference point
clockwise	order in clockwise or anticlockwise manner

Examples

#Generate a random set of points and put them clockwise order
set.seed(1)
x  = runif(100)
y  = runif(100)
op    = orderPoints(x,y)

#To demonstrate, Lets view the points in order
library(ggplot2)
df    = data.frame(x,y)
df    = df[op,];
df$id = 1:nrow(df)
ggplot(data=df,aes(x,y,colour=id)) +
    geom_path() + geom_point() +
    scale_colour_gradient(low="green",high="red")

Example output

Loading required package: geometry
Loading required package: magic
Loading required package: abind

contoureR documentation built on May 2, 2019, 12:08 p.m.