gdal_cmd_builder
Helper function for building GDAL commands.
gdal_cmd_builder( executable, parameter_variables = c(), parameter_values = c(), parameter_order = c(), parameter_noflags = c(), parameter_doubledash = c(), parameter_noquotes = c(), gdal_installation_id = 1, python_util = FALSE, verbose = FALSE )
executable |
Character. The GDAL command to use (e.g. "gdal_translate") |
parameter_variables |
List. A list of parameter names, organized by type. |
parameter_values |
List. A list of the parameters names/values. |
parameter_order |
Character. The order of the parameters for the GDAL command. |
parameter_noflags |
Character. Parameters which do not have a flag. |
parameter_doubledash |
Character. Parameters which should have a double dash "–". |
parameter_noquotes |
Character. Parameters which should not be wrapped in quotes (vector parameters only, at present). |
gdal_installation_id |
Numeric. The ID of the GDAL installation to use. Defaults to 1. |
python_util |
Logical. Is the utility a python utility? Default = FALSE. |
verbose |
Logical. Enable verbose execution? Default is FALSE. |
This function takes the executable name (e.g. "gdal_translate"), a list of parameter names organized by logical, vector, scalar, character, repeatable, a list of values of these parameters, the order they should be used in the GDAL command, and a list of parameters that should not have a flag, and returns a properly formatted GDAL command (with the full path-to-executable) that should work with a system() call.
Sometimes, a user may not want to use the most recent GDAL install (gdal_installation_id=1), so the gdal_installation_id can be used to set a different install. This is often used with gdal_chooseInstallation if, for instance, the particular GDAL installation required needs a specific driver that may not be available in all installations.
In general, an end user shouldn't need to use this function – it is used by many of the GDAL wrappers within gdalUtils.
Formatted GDAL command for use with system() calls.
Jonathan A. Greenberg (gdalUtils@estarcion.net)
## Not run:
# This builds a gdal_translate command.
executable <- "gdal_translate"
parameter_variables <- list(
logical = list(
varnames <- c("strict","unscale","epo",
"eco","q","sds","stats")),
vector = list(
varnames <- c("outsize","scale","srcwin",
"projwin","a_ullr","gcp")),
scalar = list(
varnames <- c("a_nodata")),
character = list(
varnames <- c("ot","of","mask","expand","a_srs",
"src_dataset","dst_dataset")),
repeatable = list(
varnames <- c("b","mo","co")))
parameter_order <- c(
"strict","unscale","epo","eco","q","sds","stats",
"outsize","scale","srcwin","projwin","a_ullr","gcp",
"a_nodata",
"ot","of","mask","expand","a_srs",
"b","mo","co",
"src_dataset","dst_dataset")
parameter_noflags <- c("src_dataset","dst_dataset")
# Now assign some parameters:
parameter_values = list(
src_dataset = "input.tif",
dst_dataset = "output.envi",
of = "ENVI",
strict = TRUE
)
cmd <- gdal_cmd_builder(
executable=executable,
parameter_variables=parameter_variables,
parameter_values=parameter_values,
parameter_order=parameter_order,
parameter_noflags=parameter_noflags)
cmd
system(cmd,intern=TRUE)
## End(Not run)Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.