R: Orientation Angles of Line Segments

angles.psp {spatstat} | R Documentation

## Orientation Angles of Line Segments

### Description

Computes the orientation angle of each line segment in a line segment pattern.

### Usage

      angles.psp(x, directed=FALSE)

### Arguments

`x` | A line segment pattern (object of class `"psp"`).
`directed` | Logical flag. See details.

### Details

For each line segment, the angle of inclination to the x-axis (in radians) is computed, and the angles are returned as a numeric vector.

If `directed=TRUE`, the directed angle of orientation is computed. The angle respects the sense of direction from `(x0,y0)` to `(x1,y1)`. The values returned are angles in the full range from -π to π. The angle is computed as `atan2(y1-y0,x1-x0)`. See `atan2`.

If `directed=FALSE`, the undirected angle of orientation is computed. Angles differing by π are regarded as equivalent. The values returned are angles in the range from 0 to π. These angles are computed by first computing the directed angle, then adding π to any negative angles.

### Value

Numeric vector.

### Author(s)

Adrian Baddeley Adrian.Baddeley@curtin.edu.au

and Rolf Turner r.turner@auckland.ac.nz

### See Also

`summary.psp`, `midpoints.psp`, `lengths.psp`

### Examples

      a <- psp(runif(10), runif(10), runif(10), runif(10), window=owin())
      b <- angles.psp(a)

[Package spatstat version 1.54-0 Index]