berryFunctions (version 1.11.0)

distance: Distance between points

Description

Calculate distance between points on planar surface

Usage

distance(x, y, xref, yref, along = FALSE)

Arguments

x

vector with x-coordinate(s) of point(s)

y

ditto for y

xref

single x coordinate of reference point

yref

ditto for y

along

Logical: Should distances be computed along vector (x,y)? If TRUE, (xref,yref) are ignored. If both (xref,yref) are not given, along is set to TRUE.

Value

vector with the distances

Details

The function is quite simple: sqrt((xref - x)^2 + (yref - y)^2)

See Also

nndist in the package spatstat for distance to nearest neighbour

Examples

A <- c(3,  9,-1)
B <- c(7, -2, 4)
plot(A,B)
text(A,B, paste0("P",1:3), adj=1.1)
points(3,5, col=2, pch=16)
segments(3,5, A,B)
distance(A,B, 3,5)
text(c(3.2,6,1), c(6,1,4), round(distance(A,B, 3,5),2) )