Reports the bands documented in each product's readme — what each one measures, its units, its measurement scale, and its valid range — so the variables available for extraction can be browsed without opening a readme or a raster.
Arguments
- theme
Optional character; theme folder name(s) to keep, e.g.
"elevation". Matched case-insensitively.- product
Optional character; product name(s) or catalogue id(s), e.g.
"soilgrids_250_v2_ab"or"geoscientificInformation/soilgrids_250_v2_ab". Matched case-insensitively: exactly first, and if nothing matches exactly, as a substring, so a fragment of a long product name is enough.- verbose
Logical; if
TRUE(default), print a compact summary and return the table invisibly.- ...
Passed to
build_catalogue(), e.g.root,refresh, orfiles.
Value
A data.frame with one row per band: product (the
product's catalogue id), name, theme, band, measure,
units, scale, valid_range, and description. Classed
sciSpatial_variables unless verbose = FALSE.
Details
Bands belong to the product, not to a variant: the data management guide records them once in the product readme, since resampling a layer does not change what its bands measure. A product with several variants therefore contributes one set of rows, not one set per variant.
Products whose readme documents no bands are listed with band
NA rather than dropped, so a documentation gap is visible
instead of looking like an absent product. check_metadata()
reports the same gaps against the required template fields.
See also
list_layers() for the layers themselves,
layer_meta() for one layer's full metadata.
Examples
if (FALSE) { # \dontrun{
list_variables()
list_variables(theme = "geoscientificInformation")
list_variables(product = "soilgrids")
# Every band measuring pH, across the catalogue.
v <- list_variables(verbose = FALSE)
v[grepl("pH", v$measure, ignore.case = TRUE), ]
} # }