
Create an object that represents a spatial function which has been evaluated or sampled at an irregular set of points.
ssf(loc, val)
The spatial locations at which the function has been evaluated.
A point pattern (object of class "ppp"
).
The function values at these locations.
A numeric vector with one entry for each point of loc
,
or a data frame with one row for each point of loc
.
Object of class "ssf"
.
An object of class "ssf"
represents a real-valued or
vector-valued function that has been evaluated or sampled at an
irregular set of points. An example would be a spatial covariate
that has only been measured at certain locations.
An object of this class also inherits the class "ppp"
,
and is essentially the same as a marked point pattern, except
for the class membership which enables it to be
handled in a different way.
There are methods for plot
, print
etc; see
plot.ssf
and methods.ssf
.
Use unmark
to extract only the point
locations, and marks.ssf
to extract only the function values.
# NOT RUN {
ssf(cells, nndist(cells, k=1:3))
# }
Run the code above in your browser using DataLab