finalDirection: Final direction

Description Usage Arguments Value Author(s) References See Also Examples

Description

Get the final direction (bearing) when arriving at p2 after starting from p1 and following the shortest path on an ellipsoid (following a geodetic) or on a sphere (following a great circle).

Usage

1
finalBearing(p1, p2, a=6378137, f=1/298.257223563, sphere=FALSE)

Arguments

p1

longitude/latitude of point(s). Can be a vector of two numbers, a matrix of 2 columns (first column is longitude, second column is latitude) or a SpatialPoints* object

p2

as above

a

major (equatorial) radius of the ellipsoid. The default value is for WGS84

f

ellipsoid flattening. The default value is for WGS84

sphere

logical. If TRUE, the bearing is computed for a sphere, instead of for an ellipsoid

Value

A vector of directions (bearings) in degrees

Author(s)

This function calls GeographicLib code by C.F.F. Karney

References

C.F.F. Karney, 2013. Algorithms for geodesics, J. Geodesy 87: 43-55. https://dx.doi.org/10.1007/s00190-012-0578-z. Addenda: http://geographiclib.sf.net/geod-addenda.html. Also see http://geographiclib.sourceforge.net/

See Also

bearing

Examples

1
2
bearing(c(10,10),c(20,20))
finalBearing(c(10,10),c(20,20))

geosphere documentation built on April 6, 2018, 3:03 p.m.