Get the nearest point on a segment to a given point

This function calculates the coordinates of and the distance to the nearest point on a segment to a given point. This function does not work with geographic coordinates.

nearestPointOnSegment(s, p)

Arguments

s

A matrix representing the coordinates of the segment. The matrix has 2x2 dimension where each row represents one of the end points.
p

A vector representing the X and Y coordinates of the point.

Value

A vector with three numeric values representing X and Y coordinates of the nearest point on a segment to a given point as well as the distance between both points.

References

The function was ported to R based on this code: http://pastebin.com/n9rUuGRh

Author

German Carrillo

See also

nearestPointOnLine, snapPointsToLines

Examples

segment = cbind(c(1,2),c(1,1.5))
point = c(1.2,1.5)
nearestPointOnSegment(segment, point)

#>         X         Y  distance 
#> 1.3600000 1.1800000 0.3577709