Extract.lpp: Extract Subset of Point Pattern on Linear Network
Description
Extract a subset of a point pattern on a linear network.
Usage
## S3 method for class 'lpp':
[(x, i, ...)
Arguments
x
A point pattern on a linear network (object of class "lpp").
i
Subset index. A valid subset index in the usual Rsense,
indicating which points should be retained.
...
Ignored.
Value
A point pattern on a linear network (of class "lpp").
Details
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 Rsense:
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.
Use the function unmark to remove marks from a
marked point pattern.