gdal: functions to interact with gdal not meant to be called...

Description Usage Arguments Details Value Examples

Description

functions to interact with gdal not meant to be called directly by users (but e.g. by stars::st_stars)

Usage

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gdal_read(x, ..., options = character(0), driver = character(0),
  read_data = TRUE, NA_value = NA_real_,
  RasterIO_parameters = list())

gdal_write(x, ..., file, driver = "GTiff", options = character(0),
  type = "Float32", NA_value = NA_real_, geotransform,
  update = FALSE)

gdal_inv_geotransform(gt)

gdal_crs(file, options = character(0))

gdal_metadata(file, domain_item = character(0), options = character(0),
  parse = TRUE)

gdal_subdatasets(file, options = character(0), name = TRUE)

gdal_polygonize(x, mask = NULL, file = tempfile(), driver = "GTiff",
  use_integer = TRUE, geotransform,
  breaks = classInt::classIntervals(na.omit(as.vector(x[[1]])))$brks,
  use_contours = FALSE, contour_lines = FALSE, connect8 = FALSE, ...)

gdal_rasterize(sf, x, gt, file, driver = "GTiff",
  options = character())

Arguments

x

character vector, possibly of length larger than 1 when more than one raster is read

...

ignored

options

character; raster layer read options

driver

character; when empty vector, driver is auto-detected.

read_data

logical; if FALSE, only the imagery metadata is returned

NA_value

(double) non-NA value to use for missing values; if NA, when writing missing values are not specially flagged in output dataset, when reading the default (dataset) missing values are used (if present / set).

RasterIO_parameters

list with named parameters to GDAL's RasterIO; see the stars::read_stars documentation.

file

character; file name

type

gdal write type

geotransform

length 6 numeric vector with GDAL geotransform parameters.

update

logical; TRUE if in an existing raster file pixel values shall be updated.

gt

double vector of length 6

domain_item

character vector of length 0, 1 (with domain), or 2 (with domain and item); use "" for the default domain, use NA_character_ to query the domain names.

parse

logical; should metadata be parsed into a named list (TRUE) or returned as character data?

name

logical; retrieve name of subdataset? If FALSE, retrieve description

mask

stars object with NA mask (0 where NA), or NULL

use_integer

boolean; if TRUE, raster values are read as (and rounded to) unsigned 32-bit integers values; if FALSE they are read as 32-bit floating points numbers. The former is supposedly faster.

breaks

numeric vector with break values for contour polygons (or lines)

use_contours

logical;

contour_lines

logical;

connect8

logical; if TRUE use 8 connection algorithm, rather than 4

sf

object of class sf

Details

gdal_inv_geotransform returns the inverse geotransform

gdal_crs reads coordinate reference system from GDAL data set

get_metadata gets metadata of a raster layer

gdal_subdatasets returns the subdatasets of a gdal dataset

Value

object of class crs, see st_crs.

named list with metadata items

gdal_subdatasets returns a zero-length list if file does not have subdatasets, and else a named list with subdatasets.

Examples

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## Not run: 
  f = system.file("tif/L7_ETMs.tif", package="stars")
  f = system.file("nc/avhrr-only-v2.19810901.nc", package = "stars")
  gdal_metadata(f)
  gdal_metadata(f, NA_character_)
  try(gdal_metadata(f, "wrongDomain"))
  gdal_metadata(f, c("", "AREA_OR_POINT"))

## End(Not run)

sf documentation built on July 24, 2019, 5:05 p.m.