intersect.owin {spatstat} | R Documentation |
Yields the intersection, union or set subtraction of two windows.
intersect.owin(A, B, ..., fatal=TRUE) union.owin(A,B, ...) setminus.owin(A,B, ...)
A |
A window object (see Details). |
B |
A window object. |
... |
Optional arguments passed to |
fatal |
Logical. Determines what happens if the intersection is empty. |
The function intersect.owin
computes the intersection between the
two windows A
and B
, while
union.owin
computes their union.
The function setminus.owin
computes the intersection of
A
with the complement of B
.
The arguments A
and B
must be window objects
(either objects of class "owin"
, or data that can be
coerced to this class by as.owin
).
If the intersection is empty, then if fatal=FALSE
the result is NULL, while if fatal=TRUE
an error occurs.
The intersection or union of more than two windows can also be
computed. For intersect.owin
and union.owin
the
arguments ...
can include additional window objects.
A window (object of class "owin"
).
Adrian Baddeley Adrian.Baddeley@csiro.au http://www.maths.uwa.edu.au/~adrian/ and Rolf Turner r.turner@auckland.ac.nz
is.subset.owin
,
overlap.owin
,
bounding.box
,
owin.object
# rectangles u <- unit.square() v <- owin(c(0.5,3.5), c(0.4,2.5)) # polygon data(letterR) # mask m <- as.mask(letterR) # two rectangles intersect.owin(u, v) union.owin(u,v) setminus.owin(u,v) # polygon and rectangle intersect.owin(letterR, v) union.owin(letterR,v) setminus.owin(letterR,v) # mask and rectangle intersect.owin(m, v) union.owin(m,v) setminus.owin(m,v) # mask and polygon p <- rotate(v, 0.2) intersect.owin(m, p) union.owin(m,p) setminus.owin(m,p) # two polygons A <- letterR B <- rotate(letterR, 0.2) plot(bounding.box(A,B), main="intersection") w <- intersect.owin(A, B) plot(w, add=TRUE, col="lightblue") plot(A, add=TRUE) plot(B, add=TRUE) plot(bounding.box(A,B), main="union") w <- union.owin(A,B) plot(w, add=TRUE, col="lightblue") plot(A, add=TRUE) plot(B, add=TRUE) plot(bounding.box(A,B), main="set minus") w <- setminus.owin(A,B) plot(w, add=TRUE, col="lightblue") plot(A, add=TRUE) plot(B, add=TRUE) # intersection and union of three windows C <- shift(B, c(0.2, 0.3)) plot(union.owin(A,B,C)) plot(intersect.owin(A,B,C))