pixellate(x, ..., W=NULL, weights = NULL, padzero=FALSE)## S3 method for class 'ppp':
as.im(X, \dots)
"ppp").as.mask to determine
the pixel resolution"owin") determining
the pixel raster."im").x into a pixel
image, by counting the number of points (or the total weight of
points) falling in each pixel. The function as.im.ppp is a method for the generic
function as.im for the class of point patterns. It is
equivalent to calling pixellate with its default
values. The function pixellate has additional arguments for
greater flexibility.
The pixel raster (in which points are counted) is determined
by the argument W if it is present (for pixellate only).
In this case W should be a binary mask (a window object of
class "owin" with type "mask").
Otherwise the pixel raster is determined by
extracting the window containing x and converting it to a
binary pixel mask using as.mask. The arguments
... are passed to as.mask to
control the pixel resolution.
If weights is NULL, then for each pixel
in the mask, the algorithm counts how many points in x fall
in the pixel. This count is usually either 0 (for a pixel with no data
points in it) or 1 (for a pixel containing one data point) but may be
greater than 1. The result is an image with these counts as its pixel values.
If weights is given, it should be a numeric vector of the same
length as the number of points in x. For each pixel, the
algorithm finds the total weight associated with points in x that fall
in the given pixel. The result is an image with these total weights
as its pixel values.
By default (if zeropad=FALSE) the resulting pixel image has the same
spatial domain as the window of the point pattern x. If
zeropad=TRUE then the resulting pixel image has a rectangular
domain; pixels outside the original window are assigned the value zero.
im, as.im,
density.ppp, smooth.ppp.data(humberside)
plot(pixellate(humberside))Run the code above in your browser using DataLab