plot.nnt {donut} | R Documentation |

## Plot diagnostics for an nnt object

### Description

`plot`

method for an object of class `c("nnt")`

.

### Usage

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

### Arguments

`x` |
an object of class |

`...` |

### Details

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`

.

### Value

Nothing is returned.

### Examples

See the examples in `nnt`

.

### See Also

`nnt`

for nearest neighbour with some variables
wrapped on a torus.

*donut*version 1.0.3 Index]