convexHullAM {contoureR} | R Documentation |
Convex Hull via Andrews Monotone, Rcpp Interface to C++ Routine
Description
This function is the R interface to the C++ implementation of Andrews Monotone, a well known algorithm for solving
the convex hull in O(nlogn)
time complexity.
Usage
convexHullAM_Indexes(x, y, includeColinear=FALSE,zeroBased = TRUE)
convexHullAM_Points(x, y,includeColinear=FALSE)
Arguments
x |
NumericVector of x values |
y |
NumericVector of y values |
includeColinear |
whether to inlude points that line ON the hull, by default this is set to FALSE, as this is the true definition of the convex hull. |
zeroBased |
Whether the return indexes should be zero based (true, for use in C++), or One-Based (false, for use in R). |
Value
convexHullAM_Indexes
returns an integer vector of the indexes of the points,
whilst convexHullAM_Points
returns an n x 2
matrix of the points themselves.
Examples
library(contoureR)
library(ggplot2)
set.seed(1)
x = runif(100)
y = runif(100)
ch = convexHullAM_Indexes(x,y,includeColinear=FALSE,zeroBased = FALSE)
ggplot(data.frame(x,y),aes(x,y)) +
geom_point() +
geom_path(data=data.frame(x,y)[ch,],colour="red")
[Package contoureR version 1.0.5 Index]