Creates a multidimensional space-time point pattern with any kind of coordinates and marks.
ppx(data, domain=NULL, coord.type=NULL, simplify=FALSE)
The coordinates and marks of the points.
A data.frame
or hyperframe
.
Optional. The space-time domain containing the points.
An object in some appropriate format, or NULL
.
Character vector specifying how each column of
data
should be interpreted: as a spatial coordinate,
a temporal coordinate, a local coordinate or a mark.
Entries are partially matched to the values
"spatial"
,
"temporal"
,
"local"
and
"mark"
.
Logical value indicating whether to simplify the result
in special cases.
If simplify=TRUE
, a two-dimensional point pattern
will be returned as an object of class "ppp"
,
and a three-dimensional point pattern will be returned as
an object of class "pp3"
.
If simplify=FALSE
(the default) then the result is always
an object of class "ppx"
.
Usually an object of class "ppx"
.
If simplify=TRUE
the result may be an object of
class "ppp"
or "pp3"
.
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,
any number of local 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,
a local coordinate, or a mark variable.
The argument coord.type
determines how each column is interpreted.
It should be a character vector, of length equal to the number of
columns of data
. It should contain strings that partially match
the values "spatial"
, "temporal"
, "local"
and
"mark"
. (The first letters will be sufficient.)
By default (if coord.type
is missing or NULL
),
columns of numerical data are assumed to represent
spatial coordinates, while other columns are assumed to be marks.
# NOT RUN {
df <- data.frame(x=runif(4),y=runif(4),t=runif(4),
age=rep(c("old", "new"), 2),
size=runif(4))
X <- ppx(data=df, coord.type=c("s","s","t","m","m"))
X
val <- 20 * 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
# }
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