SpatialGDAL-class {rgdal}R Documentation

Class "SpatialGDAL"

Description

Class for spatial attributes that have spatial locations on a (full) regular grid on file, not (yet) actually read.

Usage

## S3 method for class 'SpatialGDAL':
open(con, ..., silent = FALSE)
## S3 method for class 'SpatialGDAL':
close(con, ...)
copy.SpatialGDAL(dataset, fname, driver = getDriver(dataset@grod), strict = FALSE, options = NULL, silent = FALSE)

Arguments

con file name of grid map for opening, SpatialGDAL object for closing
... other arguments (currently ignored)
silent logical; if TRUE, comment and non-fatal CPL driver errors suppressed
dataset object of class SpatialGDAL
fname file name of grid map
driver GDAL driver name
strict TRUE if the copy must be strictly equivalent, or more normally FALSE indicating that the copy may adapt as needed for the output format
options driver-specific options to be passed to the GDAL driver

Objects from the Class

Objects can be created by calls of the form open. SpatialGDAL(name), , where name is the name of the GDAL file.

Slots

points:
see SpatialPoints; points slot which is not actually filled with all coordinates (only with min/max)
grid:
see GridTopology-class; grid parameters
grid.index:
see SpatialPixels-class; this slot is of zero length for this class, as the grid is full
bbox:
Object of class "matrix"; bounding box
proj4string:
Object of class "CRS"; projection
data:
Object of class data.frame, containing attribute data

Extends

Class Spatial-class, directly.

Methods

[
signature(x = "SpatialGDAL", i, j, ...): selects rows (i), columns (j), and bands (third argument); returns an object of class SpatialGridDataFrame-class. Only the selection is actually read.
[[
signature(i): reads band i and returns the values as a numeric vector

Note

Non-fatal CPL errors may be displayed for some drivers, currently for the AIG ArcInfo 9.3 binary raster driver using GDAL >= 1.6.2; the data has been read correctly, but the contents of the info directory did not meet the specifications used to reverse engineer the driver used in GDAL (see http://trac.osgeo.org/gdal/ticket/3031)

Author(s)

Edzer J. Pebesma, e.pebesma@geo.uu.nl

See Also

SpatialGridDataFrame-class, which is actually sub-classed.

Examples

x <- open.SpatialGDAL(system.file("external/test.ag", package="sp")[1])
image(x[])
image(as(x, "SpatialGridDataFrame"))
summary(as(x, "SpatialGridDataFrame"))
spplot(as(x, "SpatialGridDataFrame"))
# select first 50 rows:
summary(x[1:50])
# select first 50 columns:
summary(x[,1:50])
# select band 1:
summary(x[,,1])
# select first 50 rows, first 50 columns, band 1:
summary(x[1:50,1:50,1])
# get values of first band:
summary(x[[1]])
close(x)

[Package rgdal version 0.6-24 Index]