R: Plot a Point Matching

plot.pppmatching {spatstat.geom} | R Documentation

## Plot a Point Matching

### Description

Plot an object of class `"pppmatching"` which represents a matching of two planar point patterns.

### Usage

    ## S3 method for class 'pppmatching'
    plot(x, addmatch = NULL, main = NULL, ..., adjust = 1)

### Arguments

`x` | Point pattern matching object (class `"pppmatching"`) to be plotted.
`addmatch` | Optional. A matrix indicating additional pairs of points that should be matched. See Details.
`main` | Main title for the plot.
`...` | Additional arguments passed to other plot methods.
`adjust` | Adjustment factor for the widths of line segments. A positive number.

### Details

The object `x` represents a matching found between two point patterns `X` and `Y`. The matching may be incomplete. See `pppmatching.object` for further description.

This function plots the matching by drawing the two point patterns `X` and `Y` as red and blue dots respectively, and drawing line segments between each pair of matched points. The width of the line segments is proportional to the strength of matching. The proportionality constant can be adjusted using the argument `adjust`.

Additional graphics arguments `...` control the plotting of the window (and are passed to `plot.owin`) and the plotting of the line segments (and are passed to `plot.psp`, and ultimately to the base graphics function `polygon`).

The argument `addmatch` is for use mainly by developers to study algorithms which update the matching. If `addmatch` is given, it should be a matrix with dimensions `npoints(X) * npoints(Y)`. If `addmatch[i,j] > 0` then a light grey line segment will be drawn between `X[i]` and `Y[j`.

### Value

Null.

### Author(s)

Dominic Schuhmacher and Adrian Baddeley Adrian.Baddeley@curtin.edu.au.

### See Also

`pppmatching.object`

### Examples

      X <- runifrect(7)
      Y <- runifrect(7)
      am <- r2dtable(1, rep(10,7), rep(10,7))[[1]]/10
      m2 <- pppmatching(X, Y, am)
      plot(m2, adjust=0.3)

[Package spatstat.geom version 2.2-0 Index]