cut.lpp
Classify Points in a Point Pattern on a Network
For a point pattern on a linear network, classify the points into distinct types according to the numerical marks in the pattern, or according to another variable.
Usage
# S3 method for lpp
cut(x, z=marks(x), ...)Arguments
- x
A point pattern on a linear network (object of class
"lpp").- z
Data determining the classification. A numeric vector, a factor, a pixel image on a linear network (class
"linim"), a function on a linear network (class"linfun"), a tessellation on a linear network (class"lintess"), a string giving the name of a column of marks, or one of the coordinate names"x","y","seg"or"tp".- …
Arguments passed to
cut.default. They determine the breakpoints for the mapping from numerical values inzto factor values in the output. Seecut.default.
Details
This function has the effect of classifying each point in the point
pattern x into one of several possible types. The
classification is based on the dataset z, which may be either
a factor (of length equal to the number of points in
z) determining the classification of each point inx. Levels of the factor determine the classification.a numeric vector (of length equal to the number of points in
z). The range of values ofzwill be divided into bands (the number of bands is determined by…) andzwill be converted to a factor usingcut.default.a pixel image on a network (object of class
"linim"). The value ofzat each point ofxwill be used as the classifying variable.a function on a network (object of class
"linfun", seelinfun). The value ofzat each point ofxwill be used as the classifying variable.a tessellation on a network (object of class
"lintess", seelintess). Each point ofxwill be classified according to the tile of the tessellation into which it falls.a character string, giving the name of one of the columns of
marks(x), if this is a data frame.a character string identifying one of the coordinates: the spatial coordinates
"x","y"or the segment identifier"seg"or the fractional coordinate along the segment,"tp".
The default is to take z to be the vector of marks in
x (or the first column in the data frame of marks of x,
if it is a data frame). If the marks are numeric, then the range of values
of the numerical marks is divided into several intervals, and each
interval is associated with a level of a factor.
The result is a
marked point pattern, on the same linear network,
with the same point locations as
x, but with the numeric mark of each point discretised
by replacing it by the factor level.
This is a convenient way to transform a marked point pattern
which has numeric marks into a multitype point pattern,
for example to plot it or analyse it. See the examples.
To select some points from x, use the subset operators
[.lpp or subset.lpp instead.
Value
A multitype point pattern on the same linear network,
that is, a point pattern object
(of class "lpp") with a marks vector that is a factor.
See Also
Examples
# NOT RUN {
X <- runiflpp(20, simplenet)
f <- linfun(function(x,y,seg,tp) { x }, simplenet)
plot(cut(X, f, breaks=4))
plot(cut(X, "x", breaks=4))
plot(cut(X, "seg"))
# }