gcIntersect function

Intersections of two great circles

Get the two points where two great cricles cross each other. Great circles are defined by two points on it. 1.1

gcIntersect(p1, p2, p3, p4)

Arguments

• p1: Longitude/latitude of a single point, in degrees; can be a vector of two numbers, a matrix of 2 columns (first one is longitude, second is latitude) or a SpatialPoints* object
• p2: As above
• p3: As above
• p4: As above

Returns

two points for each pair of great circles

See Also

gcIntersectBearing

References

https://www.edwilliams.org/intersect.htm

Author(s)

Robert Hijmans, based on equations by Ed Williams (see reference)

Examples

p1 <- c(5,52); p2 <- c(-120,37); p3 <- c(-60,0); p4 <- c(0,70)
gcIntersect(p1,p2,p3,p4)