R: Identify Segments in a Line Segment Pattern

identify.psp {spatstat.geom} | R Documentation

## Identify Segments in a Line Segment Pattern

### Description

If a line segment pattern is plotted in the graphics window, this function will find the segment which is nearest to the mouse position, and print its serial number.

### Usage

      ## S3 method for class 'psp'
    identify(x, ..., labels=seq_len(nsegments(x)), n=nsegments(x), plot=TRUE)

### Arguments

`x` | A line segment pattern (object of class `"psp"`).
`labels` | Labels associated with the segments, to be plotted when the segments are identified. A character vector or numeric vector of length equal to the number of segments in `x`.
`n` | Maximum number of segments to be identified.
`plot` | Logical. Whether to plot the labels when a segment is identified.
`...` | Arguments passed to `text.default` controlling the plotting of the labels.

### Details

This is a method for the generic function `identify` for line segment pattern objects.

The line segment pattern `x` should first be plotted using `plot.psp`. Then `identify(x)` reads the position of the graphics pointer each time the left mouse button is pressed. It then finds the segment in the pattern `x` that is closest to the mouse position. This segment's index will be returned as part of the value of the call.

Each time a segment is identified, text will be displayed next to the point, showing its serial number (or the relevant entry of `labels`).

### Value

Vector containing the serial numbers of the segments in the pattern `x` that were identified.

### Author(s)

Adrian Baddeley Adrian.Baddeley@curtin.edu.au, Rolf Turner r.turner@auckland.ac.nz and Ege Rubak rubak@math.aau.dk

### See Also

`identify`, `identify.ppp`.

[Package spatstat.geom version 2.3-2 Index]