plot.nnt {donut}R Documentation

Plot diagnostics for an nnt object


plot method for an object of class c("nnt").


## S3 method for class 'nnt'
plot(x, ...)



an object of class c("nnt"), a result of a call to nnt.


Further arguments to be passed to plot, or points.


This function is only applicable in 1 or 2 dimensions, that is, when ncol(x$data) = 1 or 2. It provides a visual check that the wrapping of variables is working as intended, in cases where the number of query points, that is, nrow(x$query) is small enough that sets of nearest neighbours do not overlap much.

If ncol(x$data) = 1 then the index of each observation is plotted against its value, using a plotting character pch = 1. A vertical line is superimposed at each value in x$query and the x$k$ nearest neighbours of each line are colour-coded.

If ncol(x$data) = 2 then x$data[, 2] is plotted against x$data[, 1], using a plotting character pch = 1. Each point in x$query is plotted with a cross and the x$k$ nearest neighbours of each point are colour-coded.

Colours of the lines/crosses and nearest neighbour points can be set sing an argument col. If a variable is wrapped then the default plotting limits are set using the corresponding values in x$ranges.


Nothing is returned.


See the examples in nnt.

See Also

nnt for nearest neighbour with some variables wrapped on a torus.

[Package donut version 1.0.3 Index]