R: Place Points Evenly Along Specified Lines

pointsOnLines {spatstat} | R Documentation

## Place Points Evenly Along Specified Lines

### Description

Given a line segment pattern, place a series of points at equal distances along each line segment.

### Usage

    pointsOnLines(X, eps = NULL, np = 1000, shortok=TRUE)

### Arguments

`X` | A line segment pattern (object of class `"psp"`).
`eps` | Spacing between successive points.
`np` | Approximate total number of points (incompatible with `eps`).
`shortok` | Logical. If `FALSE`, very short segments (of length shorter than `eps`) will not generate any points. If `TRUE`, a very short segment will be represented by its midpoint.

### Details

For each line segment in the pattern `X`, a succession of points is placed along the line segment. These points are equally spaced at a distance `eps`, except for the first and last points in the sequence.

The spacing `eps` is measured in coordinate units of `X`.

If `eps` is not given, then it is determined by `eps = len/np` where `len` is the total length of the segments in `X`. The actual number of points will then be slightly larger than `np`.

### Value

A point pattern (object of class `"ppp"`) in the same window as `X`. The result also has an attribute called `"map"` which maps the points to their parent line segments.

### 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`, `ppp`, `runifpointOnLines`

### Examples

      X <- psp(runif(20), runif(20), runif(20), runif(20),  window=owin())
      Y <- pointsOnLines(X, eps=0.05)
      plot(X, main="")
      plot(Y, add=TRUE, pch="+")

[Package spatstat version 1.63-3 Index]