spatstat (version 1.48-0)

has.close: Check Whether Points Have Close Neighbours

Description

For each point in a point pattern, determine whether the point has a close neighbour in the same pattern.

Usage

has.close(X, r, Y=NULL, ...)
  "has.close"(X,r, Y=NULL, ..., periodic=FALSE)
  "has.close"(X,r, Y=NULL, ..., periodic=FALSE, sorted=FALSE)
  "has.close"(X,r, Y=NULL, ..., periodic=FALSE, sorted=FALSE)

Arguments

X,Y

Point patterns of class "ppp" or "pp3" or "lpp".

r

Threshold distance: a number greater than zero.

periodic

Logical value indicating whether to measure distances in the periodic sense, so that opposite sides of the (rectangular) window are treated as identical.

sorted

Logical value, indicating whether the points of X (and Y, if given) are already sorted into increasing order of the $x$ coordinates.

...

Other arguments are ignored.

Value

A logical vector, with one entry for each point of X.

Details

This is simply a faster version of (nndist(X) <= r)<="" code=""> or (nncross(X,Y,what="dist") <= r)<="" code="">.

has.close(X,r) determines, for each point in the pattern X, whether or not this point has a neighbour in the same pattern X which lies at a distance less than or equal to r.

has.close(X,r,Y) determines, for each point in the pattern X, whether or not this point has a neighbour in the other pattern Y which lies at a distance less than or equal to r.

The function has.close is generic, with methods for "ppp" and "pp3" and a default method.

See Also

nndist

Examples

  has.close(redwood, 0.05)
  with(split(amacrine), has.close(on, 0.05, off))