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 |

`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]