bdist.points {spatstat} | R Documentation |
Computes the distances from each point of a point pattern to the boundary of the window.
bdist.points(X)
X |
A point pattern (object of class "ppp" ). |
This function computes, for each point x[i]
in the point pattern X
, the shortest distance
dist(x[i], W') from x[i]
to the boundary of the window W of observation.
If the window X$window
is of type "rectangle"
or "polygonal"
, then these distances are computed by
analytic geometry and are exact, up to rounding errors.
If the window is of type "mask"
then the distances
are computed using the real-valued distance transform,
which is an approximation with maximum error equal to the width
of one pixel in the mask.
A numeric vector, giving the distances from each point of the pattern to the boundary of the window.
Adrian Baddeley adrian@maths.uwa.edu.au http://www.maths.uwa.edu.au/~adrian/ and Rolf Turner rolf@math.unb.ca http://www.math.unb.ca/~rolf
data(cells) d <- bdist.points(cells)