MeridianMERIDIAN

Measurement Unit

representation.scientific.measurement_unit

Unit of measurement (meter, kilogram, second, Joule, etc.). May be written as symbol (m, kg, s) or full name (meter, kilogram). Broad categorization.

Worked samples

DuckDB 1.5.5 · finetype 0.6.64

ValueAs VARCHAR
metermeter
kilogramkilogram
secondsecond
mm
kgkg
Joulejoule
Jj
Scope
broad_words

Told apart

1 of the 6 other scientific types accept every one of these samples on shape alone.

Background

Origin

The International System of Units, the SI, was established in 1960 by a resolution at the 11th meeting of the General Conference on Weights and Measures (CGPM).[1] The SI Brochure, which sets out the system, is published by the International Bureau of Weights and Measures (BIPM).[1] The SI Brochure says that the seven base units and the 22 units with special names form the core of the set of SI units, and that all other SI units are combinations of these 29 units.[1]

The capital L was adopted as an alternative symbol for the litre by the 16th CGPM in 1979, to avoid confusion between the letter l and the numeral 1.[1]

Use

The SI Brochure says unit symbols are printed in lower-case letters unless they are derived from a proper name, in which case the first letter is a capital.[1] The SI Brochure says unit symbols are mathematical entities, not abbreviations, so they take no full stop except at the end of a sentence and no plural.[1] The SI Brochure rules out abbreviations such as sec for s or second, and cc for cm3 or cubic centimetre.[1] The SI Brochure gives degree Celsius as the correct spelling of the name of the unit with the symbol °C.[1] Wikipedia's article on the SI notes that NIST recommends the symbol L for the litre within the United States.[2]

The Unified Code for Units of Measure (UCUM) is a code system intended to include all units of measures being contemporarily used in international science, engineering, and business.[3] The UCUM specification says its focus is on electronic communication, as opposed to communication between humans.[3] The UCUM specification says ISO 2955 and ANSI X3.50 contain numerous name conflicts, such as cd meaning both candela and centi-day.[3] UCUM defines a case-insensitive variant for every terminal symbol, to be used when there is a risk of upper and lower case being confused.[3] HL7's FHIR R4 specification says that if a Quantity's unit can be coded in UCUM and a code is provided, the code SHOULD be a UCUM code.[4] HL7's FHIR R4 specification warns that a Quantity's unit element will often contain a valid UCUM unit, but that this cannot be assumed.[4]

Sources

  1. [1]The International System of Units (SI)standard
  2. [2]International System of Unitssecondary source
  3. [3]The Unified Code for Units of Measurestandard
  4. [4]Datatypes - FHIR v4.0.1documentation

Detection notes

v1 migration: Was science.measure_unit marked broad_words. SI base units and common derived units. Supports both symbols and full names.

Use it

CLI · DuckDB
$ finetype infer -i "meter" --mode column
→ representation.scientific.measurement_unit

SELECT ft_infer('meter');
-- → 'representation.scientific.measurement_unit'
Cast expression
LOWER(CAST({col} AS VARCHAR))

Schema

https://meridian.online/schemas/representation.scientific.measurement_unit · Frictionless type string

finetype taxonomy representation.scientific.measurement_unit -o json-schema

Aliases

unit

Type Registry