Skip to contents

Generate GDALWarp Command Arguments

Source: R/ngr_spk_gdalwarp.R
ngr_spk_gdalwarp.Rd

Constructs the command-line arguments for GDAL's gdalwarp utility, allowing for flexible reprojection and resampling of raster data. The function can return either a vector of arguments for programmatic use or a complete command string for manual execution when interactive = TRUE.

Usage

ngr_spk_gdalwarp(
  path_in,
  path_out,
  s_srs = NULL,
  t_srs = "EPSG:3005",
  resampling = "bilinear",
  target_resolution = c(0.15, 0.15),
  overwrite = TRUE,
  interactive = FALSE,
  params_default = c("-multi", "-wo", "NUM_THREADS=ALL_CPUS"),
  params_add = NULL
)

Arguments

path_in

character A vector of file paths to input rasters. Must be valid file paths.

path_out

character A single file path for the output raster. The directory must exist.

s_srs

character or NULL Optional. The source spatial reference system in any GDAL-supported format (e.g., EPSG codes, PROJ strings). Defaults to NULL, meaning it will be inferred from the input raster.

t_srs

character The target spatial reference system in any GDAL-supported format. Defaults to "EPSG:3005".

resampling

character The resampling method. One of "nearest", "bilinear", "cubic", "cubicspline", "lanczos", "average", "mode". Defaults to "bilinear".

target_resolution

numeric A numeric vector of length 2 specifying the output pixel resolution in meters for the x and y directions. Defaults to c(0.15, 0.15) (15cm x 15cm pixels).

overwrite

logical Whether to overwrite the output file if it exists. Defaults to TRUE.

interactive

logical Whether to return the full gdalwarp command as a string for manual use. Defaults to FALSE.

params_default

character or NULL Optional. A character vector of default parameters to include in the gdalwarp command. Defaults to c("-multi", "-wo", "NUM_THREADS=ALL_CPUS").

params_add

character or NULL Optional. A character vector of additional parameters to include in the gdalwarp command.

Value

character A vector of arguments for programmatic use or a complete command string if interactive = TRUE.

Details

The function constructs command-line arguments for gdalwarp, enabling flexible raster reprojection, resampling, and transformation. Note that gdalwarp requires GDAL to be installed on your system. On macOS, you can install GDAL using Homebrew by running brew install gdal. For more details on gdalwarp, visit: https://gdal.org/en/stable/programs/gdalwarp.html.

See also

gdalwarp documentation

Other spacehakr: ngr_spk_ext_raster(), ngr_spk_odm(), ngr_spk_poly_to_points(), ngr_spk_res()

Other processx: ngr_spk_odm()

Examples

if (FALSE) { # \dontrun{
# Generate arguments for programmatic use
args <- ngr_spk_gdalwarp(
  path_in = c("input1.tif", "input2.tif"),
  path_out = "output.tif",
  s_srs = "EPSG:4326",
  t_srs = "EPSG:3857",
  target_resolution = c(0.1, 0.1)
)

# Generate a full command for manual use
cmd <- ngr_spk_gdalwarp(
  path_in = c("input1.tif", "input2.tif"),
  path_out = "output.tif",
  s_srs = "EPSG:4326",
  t_srs = "EPSG:3857",
  target_resolution = c(0.1, 0.1),
  interactive = TRUE
)
cat(cmd, "\n")
} # }