| Extract.lpp {spatstat} | R Documentation |
Extract a subset of a point pattern on a linear network.
## S3 method for class 'lpp' x[i, j, ...]
x |
A point pattern on a linear network (object of class |
i |
Subset index. A valid subset index in the usual R sense, indicating which points should be retained |
j |
Spatial window
(object of class |
... |
Ignored. |
This function extracts a designated subset of a point pattern on a linear network.
The function [.lpp is a method for [ for the
class "lpp". It extracts a designated subset of a point pattern.
The argument i should be a subset index in the usual R sense:
either a numeric vector
of positive indices (identifying the points to be retained),
a numeric vector of negative indices (identifying the points
to be deleted) or a logical vector of length equal to the number of
points in the point pattern x. In the latter case,
the points (x$x[i], x$y[i]) for which
subset[i]=TRUE will be retained, and the others
will be deleted.
The argument j, if present, should be a spatial window.
The pattern inside the region will be retained.
Line segments that cross the boundary of the window
are deleted in the current implementation.
Use the function unmark to remove marks from a
marked point pattern.
A point pattern on a linear network (of class "lpp").
Adrian Baddeley Adrian.Baddeley@uwa.edu.au http://www.maths.uwa.edu.au/~adrian/ and Rolf Turner r.turner@auckland.ac.nz
# Chicago crimes data - remove cases of assault chicago[marks(chicago) != "assault"]