capemlGIS: tools to generate EML metadata for spatial raster data

overview

capemlGIS is a companion package to CAPLTER/capeml that facilitates the creation of Ecological Metadata Language (EML) spatialRaster entities for publishing to the Environmental Data Initiative (EDI) data repository.

Looking for vector data (KML, GeoJSON, shapefile)? Vector metadata functionality has moved to the dedicated CAPLTER/capemlVector package.

The capeml package ecosystem:

package	scope
capeml	tabular data, dataset-level metadata
capemlVector	spatial vector data (KML, GeoJSON, shapefile)
capemlGIS	spatial raster data

installation

Install with pak:

# install pak if needed
# install.packages("pak")

pak::pak("CAPLTER/capemlGIS")

capemlGIS depends on: - capeml, which will be installed automatically via the Remotes field when using pak. - raster

getting started

Creating an EML dataset starts with the CAPLTER/capeml package. capemlGIS is designed to create EML entities of type spatialRaster; users should begin with the capeml workflow, including creating a config.yaml in the working directory that contains project-level metadata required by the raster functions.

options

EML version

This package defaults to the current version of EML. Users can switch to the previous version with emld::eml_version("eml-2.1.1").

project naming

create_raster() will name output files with the format identifier_object-name.file-extension when projectNaming = TRUE (the default). The identifier is read from config.yaml. Set projectNaming = FALSE to use the object name as-is.

functions

function	output	description
create_raster()	zipped raster file(s) + EML spatialRaster	generates EML metadata for a raster object
write_raster_factors()	_raster_factors.yaml template	creates a metadata template for categorical raster values
zipRelatedFiles()	zipped archive	zips files sharing a base name for inclusion in a data package

workflow: prepare raster factor metadata

If the raster contains categorical values, generate a factor metadata template before calling create_raster():

capemlGIS::write_raster_factors(
  raster_entity = my_raster,
  value_name    = "category_field"
)

Edit the generated yaml file to supply definitions for each category value. The file will be read automatically by create_raster().

workflow: create a spatialRaster

my_raster <- raster::raster("path/to/my_raster.img")

my_raster_desc <- "a description of the raster data entity"

my_raster_SR <- capemlGIS::create_raster(
  rasterName    = my_raster,
  description   = my_raster_desc,
  epsgProjection = 4326,
  overwrite     = TRUE,
  projectNaming = TRUE
)

# my_raster_SR is an EML spatialRaster — add it to the EML dataset