ppx
Multidimensional Space-Time Point Pattern
Creates a multidimensional space-time point pattern with any kind of coordinates and marks.
Usage
ppx(data, domain=NULL, spatial = NULL, temporal = NULL)Arguments
- data
- The coordinates and marks of the points.
A
data.frameorhyperframe. - domain
- Optional. The space-time domain containing the points.
An object in some appropriate format, or
NULL. - spatial
- Character vector giving the names of the columns of
datathat should be interpreted as spatial coordinates. - temporal
- Character vector giving the names of the columns of
datathat should be interpreted as temporal coordinates.
Details
An object of class "ppx"
represents a marked point pattern
in multidimensional space and/or time. There may be any
number of spatial coordinates, any number of temporal coordinates,
and any number of mark variables. The individual marks may be
atomic (numeric values, factor values, etc) or objects of any kind.
The argument data should contain the coordinates and marks of
the points. It should be a data.frame or more generally a
hyperframe (see hyperframe) with
one row of data for each point.
Each column of data is either
a spatial coordinate, a temporal coordinate, or a mark variable.
The argument spatial determines which columns are interpreted
as spatial coordinates: if it is present, spatial should be a
character vector matching the names of columns of data.
Similarly the argument temporal determines which columns
are interpreted as temporal coordinates.
By default, columns of numerical data are assumed to represent
spatial coordinates.
Value
- An object of class
"ppx".
See Also
Examples
df <- data.frame(x=runif(4),y=runif(4),z=runif(4))
X <- ppx(data=df, t="z")
X
val <- runif(4)
E <- lapply(val, function(s) { rpoispp(s) })
hf <- hyperframe(t=val, e=as.listof(E))
Z <- ppx(data=hf, domain=c(0,1))
Z