GDALRasterBand-class {rgdal}R Documentation

Class "GDALRasterBand"

Description

Returns a two-dimensional array with data from a raster band, used internally within functions

Usage

getRasterData(dataset, band = NULL, offset = c(0, 0),
              region.dim = dim(dataset), output.dim = region.dim,
              interleave = c(0, 0), as.is = FALSE) 

getRasterTable(dataset, band = NULL, offset = c(0, 0), 
  region.dim = dim(dataset))

getProjectionRef(dataset)

getRasterBand(dataset, band = 1)

getRasterBlockSize(raster)

toSigned(x, base)

toUnSigned(x, base)

Arguments

dataset

An object inheriting from class 'GDALReadOnlyDataset'

band

The band number (1-based) to read from

offset

Number of rows and columns from the origin (usually the upper left corner) to begin reading from; presently ordered (y,x) - this may change

region.dim

The number of rows and columns to read from the dataset; presently ordered (y,x) - this may change

output.dim

Number of rows and columns in the output data; if smaller than region.dim the data will be subsampled

interleave

Element and row stride while reading data; rarely needed

as.is

If false, scale the data to its natural units; if the case of thematic data, return the data as factors

raster

An object of class GDALRasterBand

x

integer variable for conversion

base

If Byte input, 8, if Int16 or UInt16, 16

Details

getRasterData:

retrieves data from the dataset as array.

getRasterTable:

retrieves data from the dataset as data frame.

getProjectionRef:

returns the geodetic projection in Well Known Text format.

getRasterBand:

returns a raster band

getRasterBlockSize:

returns the natural block size of the raster band. Use this for efficient tiled IO.

toSigned:

used to convert a band read as unsigned integer to signed integer

toUnSigned:

used to convert a band read as signed integer to unsigned integer

Objects from the Class

Objects can be created by calls of the form new("GDALRasterBand", dataset, band).

Slots

handle:

Object of class "externalptr", from class "GDALMajorObject", used internally; not for public consumption

Extends

Class "GDALMajorObject", directly.

Methods

dim

signature(x = "GDALRasterBand"): ...

initialize

signature(.Object = "GDALRasterBand"): ...

Author(s)

Timothy H. Keitt, modified by Roger Bivand

See Also

See also GDALDriver-class, GDALDataset-class, GDALTransientDataset-class

Examples

logo <- system.file("pictures/logo.jpg", package="rgdal")[1]
x <- new("GDALReadOnlyDataset", logo)
plot(density(getRasterTable(x)$band1))
GDAL.close(x)

[Package rgdal version 0.7-8 Index]