get the reference to a unit
get_unit_type.Rdget_unit_type will determine the reference and details
(if relevant) of a supplied string as either qudt_en_us, qudt_en_uk, custom,
or from the EML standard dictionary. The latter returns NULL.
Value
NULL if the provided string matches a reference in the EML standard unit dictionary; a tibble of unit details if in the QUDT unit dictionary, or a tibble of name and type fields if a custom unit (i.e., not in the EML standard unit dictionary or the QUDT standard unit dicationary).
Details
The unit referece is determined by comparing the provided string
against catalogues of the EML standard unit dictionary, and subsets of the
QUDT unit dictionary. The QUDT unit dictionary is segregated between units
in the english US and UK variants. get_unit_type will try first to
match the supplied string against units in the QUDT subset of enlish (US)
units and seek a match in the UK variant if a US match is not found. Units
that are in the EML standard library return NULL value as further
documentation is not required for that set. get_unit_type is designed
as a helper function for other tools within capeml that involve units
but can be used independently.