Spatial-class: Class "Spatial"
Description
An abstract class from which useful spatial classes are
derived Usage
Spatial(bbox, proj4string = CRS(as.character(NA)))
"subset"(x, subset, select, drop = FALSE, ...)
Objects from the Class
are never to be generated; only derived classes can be meaningfulSlots
bbox
:- Object of class
"matrix"
; 2-column matrix
holding the minimum in first and maximum in second column for the
x-coordinate (first row), y-coordinate (second row) and optionally,
for points and grids only, further coordinates. The constructed
Spatial object will be invalid if any bbox values are NA or infinite. The column names must be c("min", "max")
proj4string
:- Object of class
"CRS"
;
holding a valid proj4 string, which can be used for unprojecting
or reprojecting coordinates; it is initialised to NA. Other strings
are checked for validity in the rgdal package, but attempts to assign a string containing "longlat" to data extending beyond longitude [-180, 360] or lattitude [-90, 90] will be stopped or warned, use set_ll_warn
to warn rather than stop, and set_ll_TOL
to change the default tolerance for the range exceedance tests.
Methods
- bbox
signature(obj = "Spatial")
: retrieves the bbox element - dimensions
signature(obj = "Spatial")
: retrieves the number
of spatial dimensions spanned - gridded
signature(obj = "Spatial")
: logical, tells whether
the data is on a regular spatial grid - plot
signature(x = "Spatial", y = "missing")
: plot method
for spatial objects; does nothing but setting up a plotting region choosing
a suitable aspect if not given(see below), colouring the plot background using either a bg= argument or par("bg"), and possibly drawing axes. - summary
signature(object = "Spatial")
: summarize object $
- retrieves attribute column
$<-
- sets or replaces attribute column, or promote a
geometry-only object to an object having an attribute
plot method arguments
The plot method for Spatial objects takes the following arguments:
- x
- object of class Spatial
- xlim
- default NULL; the x limits (x1, x2) of the plot
- ylim
- default NULL; the y limits of the plot
- asp
- default NA; the y/x aspect ratio
- axes
- default FALSE; a logical value indicating whether both axes should be drawn
- bg
- default
par("bg")
; colour to be used for the background of the device region - xaxs
- The style of axis interval calculation to be used for the x-axis
- yaxs
- The style of axis interval calculation to be used for the y-axis
- lab
- A numerical vector of the form
c(x, y, len)
which modifies the default way that axes are annotated - setParUsrBB
- default FALSE; set the
par
usr bounding box; see below - bgMap
- object of class
ggmap
, or returned by function RgoogleMaps::GetMap
- expandBB
- numeric; factor to expand the plotting region default:
bbox(x)
with on
each side (1=below, 2=left, 3=above and 4=right); defaults to c(0,0,0,0)
;
setting xlim
or ylim
overrides this. - ...
- passed through
Warning
this class is not useful in itself, but all spatial
classes in this package derive from it