R: Interactively Add Points on a Linear Network

clicklpp {spatstat.linnet} | R Documentation

## Interactively Add Points on a Linear Network

### Description

Allows the user to create a point pattern on a linear network by point-and-click in the display.

### Usage

      clicklpp(L, n=NULL, types=NULL, ...,
               add=FALSE, main=NULL, hook=NULL)

### Arguments

`L` | Linear network on which the points will be placed. An object of class `"linnet"`.
`n` | Number of points to be added (if this is predetermined).
`types` | Vector of types, when creating a multitype point pattern.
`...` | Optional extra arguments to be passed to `locator` to control the display.
`add` | Logical value indicating whether to create a new plot (`add=FALSE`) or draw over the existing plot (`add=TRUE`).
`main` | Main heading for plot.
`hook` | For internal use only. Do not use this argument.

### Details

This function allows the user to create a point pattern on a linear network by interactively clicking on the screen display.

First the linear network `L` is plotted on the current screen device. Then the user is prompted to point the mouse at any desired locations and click the left mouse button to add each point. Interactive input stops after `n` clicks (if `n` was given) or when the middle mouse button is pressed.

The return value is a point pattern on the network `L`, containing the locations of all the clicked points, after they have been projected onto the network `L`. Any points that were clicked outside the bounding window of the network will be ignored.

If the argument `types` is given, then a multitype point pattern will be created. The user is prompted to input the locations of points of type `type[i]`, for each successive index `i`. (If the argument `n` was given, there will be `n` points of each type.) The return value is a multitype point pattern on a linear network.

This function uses the R command `locator` to input the mouse clicks. It only works on screen devices such as ‘X11’, ‘windows’ and ‘quartz’. Arguments that can be passed to `locator` through `...` include `pch` (plotting character), `cex` (character expansion factor) and `col` (colour). See `locator` and `par`.

### Value

A point pattern (object of class `"lpp"`).

### Author(s)

Adrian Baddeley Adrian.Baddeley@curtin.edu.au, Rolf Turner r.turner@auckland.ac.nz and Ege Rubak rubak@math.aau.dk, based on an idea by Dominic Schuhmacher.

### See Also

`clickppp`, `identify.lpp`, `locator`, `clickpoly`, `clickbox`, `clickdist`

[Package spatstat.linnet version 2.0-0 Index]