R: a class for spatial lines

SpatialLines-class {sp} | R Documentation

## a class for spatial lines

### Description

a class that holds spatial lines

### Objects from the Class

hold a list of Lines objects; each Lines object holds a list of Line (line) objects.

### Slots

`lines`:

  Object of class `"list"`; list members are all of class Lines-class

`bbox`:

  Object of class `"matrix"`; see Spatial-class

`proj4string`:

  Object of class `"CRS"`; see CRS-class

### Extends

Class `"Spatial"`, directly.

### Methods

[

  `signature(obj = "SpatialLines")`: select subset of (sets of) lines; NAs are not permitted in the row index

coordinates

  value is a list of lists with matrices

plot

  `signature(x = "SpatialLines", y = "missing")`: plot lines in SpatialLines object

lines

  `signature(x = "SpatialLines")`: add lines in SpatialLines object to a plot

rbind

  `signature(object = "SpatialLines")`: rbind-like method, see notes

summary

  `signature(object = "SpatialLines")`: summarize object

### plot method arguments

The plot method for “SpatialLines” objects takes the following arguments:

x

  object of class SpatialLines

xlim

  default NULL; the x limits (x1, x2) of the plot

ylim

  default NULL; the y limits of the plot

col

  default 1; default plotting color

lwd

  default 1; line width

lty

  default 1; line type

add

  default FALSE; add to existing plot

axes

  default FALSE; a logical value indicating whether both axes should be drawn

lend

  default 0; line end style

ljoin

  default 0; line join style

lmitre

  default 10; line mitre limit

...

  passed through

setParUsrBB

  set the `par` “usr” bounding box, see note in Spatial-class

### Note

`rbind` calls the function `SpatialLines`, where it is checked that all IDs are unique. If `rbind`-ing `SpatialLines` without unique IDs, it is possible to set the argument `makeUniqueIDs = TRUE`, although it is preferred to change these explicitly with `spChFIDs`.

### Author(s)

Roger Bivand, Edzer Pebesma

### See Also

Line-class, Lines-class

### Examples

    # from the sp vignette:
    l1 = cbind(c(1,2,3),c(3,2,2))
    rownames(l1) = letters[1:3]
    l1a = cbind(l1[,1]+.05,l1[,2]+.05)
    rownames(l1a) = letters[1:3]
    l2 = cbind(c(1,2,3),c(1,1.5,1))
    rownames(l2) = letters[1:3]
    Sl1 = Line(l1)
    Sl1a = Line(l1a)
    Sl2 = Line(l2)
    S1 = Lines(list(Sl1, Sl1a), ID="a")
    S2 = Lines(list(Sl2), ID="b")
    Sl = SpatialLines(list(S1,S2))
    summary(Sl)
    plot(Sl, col = c("red", "blue"))

[Package sp version 1.3-2 Index]