ArcIntersection: Point(s) at which two arcs intersect on a sphere

In laurasoul/dispeRse: Models For Paleobiogeography

Description

Given two arcs returns point(s) at which they intersect on a sphere.

Usage

ArcIntersection(
  longitude_1,
  latitude_1,
  longitude_2,
  latitude_2,
  longitude_3,
  latitude_3,
  longitude_4,
  latitude_4,
  type = c("arc", "arc"),
  EarthRad = 6367.4447
)

Arguments

longitude_1	Decimalised longitude of first point on first arc.
latitude_1	Decimalised latitude of first point on first arc.
longitude_2	Decimalised longitude of second point on first arc.
latitude_2	Decimalised latitude of second point on first arc.
longitude_3	Decimalised longitude of first point on second arc.
latitude_3	Decimalised latitude of first point on second arc.
longitude_4	Decimalised longitude of second point on second arc.
latitude_4	Decimalised latitude of second point on second arc.
type	Vector to indicate if elements are arcs or Great Circles.
EarthRad	Earth radius in kilometres.

Details

Assumes shortest distance between points describes arc. Can define Great Circle-arc intersection with type option.

Value

Matrix of longitude-latitude points at which intersection(s) occur.

Author(s)

Graeme T. Lloyd [e-mail]

Examples

longitude_1 <- stats::runif(1, -180, 180)
longitude_2 <- stats::runif(1, -180, 180)
longitude_3 <- stats::runif(1, -180, 180)
longitude_4 <- stats::runif(1, -180, 180)
latitude_1 <- stats::runif(1, -90, 90)
latitude_2 <- stats::runif(1, -90, 90)
latitude_3 <- stats::runif(1, -90, 90)
latitude_4 <- stats::runif(1, -90, 90)
ArcIntersection(longitude_1, latitude_1, longitude_2, latitude_2,
  longitude_3, latitude_3, longitude_4, latitude_4, EarthRad = 6367.4447)

laurasoul/dispeRse documentation built on May 25, 2021, 4:50 a.m.