Learn R Programming

geosphere (version 1.3-13)

dist2gc: Cross Track Distance

Description

Compute the distance of a point to a great-circle path (also referred to as the cross track distance or cross track error). The great circle is defined by p1 and p2, while p3 is the point away from the path.

Usage

dist2gc(p1, p2, p3, r=6378137)

Arguments

p1
Start of great circle path. longitude/latitude of point(s). Can be a vector of two numbers, a matrix of 2 columns (first one is longitude, second is latitude) or a SpatialPoints* object
p2
End of great circle path. As above
p3
Point away from the great cricle path. As for p2
r
radius of the earth; default = 6378137

Value

  • A distance in units of r (default is meters) The sign indicates which side of the path p3 is on. Positive means right of the course from p1 to p2, negative means left.

References

http://www.movable-type.co.uk/scripts/latlong.html http://williams.best.vwh.net/ftp/avsig/avform.txt

See Also

dist2Line, alongTrackDistance

Examples

Run this code
dist2gc(c(0,0),c(90,90),c(80,80))

Run the code above in your browser using DataLab