R: Marks of a Line Segment Pattern

marks.psp {spatstat} | R Documentation

## Marks of a Line Segment Pattern

### Description

Extract or change the marks attached to a line segment pattern.

### Usage

    ## S3 method for class 'psp'
    marks(x, ..., dfok=TRUE)
    ## S3 replacement method for class 'psp'
    marks(x, ...) <- value

### Arguments

`x` | Line segment pattern dataset (object of class `"psp"`).
`...` | Ignored.
`dfok` | Logical. If `FALSE`, data frames of marks are not permitted and will generate an error.
`value` | Vector or data frame of mark values, or `NULL`.

### Details

These functions extract or change the marks attached to each of the line segments in the pattern `x`. They are methods for the generic functions `marks` and `marks<-` for the class `"psp"` of line segment patterns.

The expression `marks(x)` extracts the marks of `x`. The assignment `marks(x) <- value` assigns new marks to the dataset `x`, and updates the dataset `x` in the current environment.

The marks can be a vector, a factor, or a data frame.

For the assignment `marks(x) <- value`, the `value` should be a vector or factor of length equal to the number of segments in `x`, or a data frame with as many rows as there are segments in `x`. If `value` is a single value, or a data frame with one row, then it will be replicated so that the same marks will be attached to each segment.

To remove marks, use `marks(x) <- NULL` or `unmark(x)`.

### Value

For `marks(x)`, the result is a vector, factor or data frame, containing the mark values attached to the line segments of `x`. If there are no marks, the result is `NULL`.

For `marks(x) <- value`, the result is the updated line segment pattern `x` (with the side-effect that the dataset `x` is updated in the current environment).

### 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

`psp.object`, `marks`, `marks<-`

### Examples

      m <- data.frame(A=1:10, B=letters[1:10])
      X <- psp(runif(10), runif(10), runif(10), runif(10), window=owin(), marks=m)

      marks(X)
      marks(X)[,2]
      marks(X) <- 42
      marks(X) <- NULL

[Package spatstat version 1.54-0 Index]