Scatterplot Matrix for Pixel Images on a Linear Network
Produces a scatterplot matrix of the pixel values in two or more pixel images on a linear network.
"pairs"(..., plot=TRUE, eps=NULL)
Any number of arguments, each of which is either
a pixel image on a linear network (object of class
"linim"), a pixel image (object of class
"im"), or a named argument to be passed to
TRUE, the scatterplot matrix is plotted.
- Optional. Spacing between sample points on the network. A positive number.
This is a method for the generic function
for the class of pixel images on a linear network.
It produces a square array of plot panels, in which each panel shows
a scatterplot of the pixel values of one image against the
corresponding pixel values of another image.
At least two of the arguments
... should be a pixel image
on a linear network (object of class
They should be defined on the same linear network,
but may have different pixel resolutions.
First the pixel values of each image are extracted at a
set of sample points equally-spaced across the network.
pairs.default is called to
plot the scatterplot matrix.
Any arguments in
... which are not pixel images will be
pairs.default to control the plot.
data.framecontaining the corresponding pixel values for each image. The return value also belongs to the class
plotpairsimwhich has a plot method, so that it can be re-plotted.
fit <- lppm(chicago ~ marks * (x+y)) lam <- predict(fit) do.call(pairs, lam)