test.crossing.psp {spatstat.geom}

Check Whether Segments Cross

Description

Determine whether there is a crossing (intersection) between each pair of line segments.

Usage

test.crossing.psp(A, B)
test.selfcrossing.psp(A)

Arguments

A, B

Line segment patterns (objects of class "psp").

Details

These functions decide whether the given line segments intersect each other.

If A and B are two spatial patterns of line segments, test.crossing.psp(A, B) returns a logical matrix in which the entry on row i, column j is equal to TRUE if segment A[i] has an intersection with segment B[j].

If A is a pattern of line segments, test.selfcross.psp(A) returns a symmetric logical matrix in which the entry on row i, column j is equal to TRUE if segment A[i] has an intersection with segment A[j].

Value

A logical matrix.

Author(s)

Adrian Baddeley [e-mail], Rolf Turner [e-mail] and Ege Rubak [e-mail].

See Also

psp

Examples

  B <- edges(letterR)
if(require(spatstat.random)) {
  A <- rpoisline(5, Frame(B))
} else {
  FB <- Frame(B)
  A <- as.psp(from=runifrect(5, FB), to=runifrect(5, FB))
}
  MA <- test.selfcrossing.psp(A)
  MAB <- test.crossing.psp(A, B)