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*Mismatch of base units between UCUM and SI #169

Open timbrisc opened 3 years ago

timbrisc commented 3 years ago

Issue migrated from trac ticket # 5788

component: help | priority: major

2021-03-01 00:00:06: simon.cox@csiro.au created the issue

The seven 'base units' in UCUM do not match the SI. See https://ucum.org/ucum.html#section-Base-Units for UCUM, and compare with https://www.bipm.org/en/measurement-units/ and select tab 'SI base units'.

Amount of substance/mole missing from UCUM base quantities/units. Plane angle is not a base quantity in SI.

I note that this deviation is discussed and justified in the UCUM spec, but it presents a barrier to advocating for the use of UCUM in the context of SI.

timbrisc commented 3 years ago

2020-11-03 22:28:49: timbrisc@loinc.org changed status from new to closed

timbrisc commented 3 years ago

2020-11-03 22:28:49: timbrisc@loinc.org set resolution to spam

timbrisc commented 3 years ago

2021-03-01 00:01:28: simon.cox@csiro.au edited the issue description

timbrisc commented 3 years ago

2021-03-01 00:01:28: simon.cox@csiro.au changed title from Amount of substance/mole missing from base quantities/units to Mismatch of base units between UCUM and SI

timbrisc commented 2 years ago

2021-11-02 21:12:54: mitchbre@regenstrief.org changed title from Mismatch of base units between UCUM and SI to *Mismatch of base units between UCUM and SI

chgessner commented 1 year ago

I am in favor of adding the mole as a base unit (using the newly proposed Avogadro constant to capture the numerical value, see https://github.com/ucum-org/ucum/pull/242#issuecomment-1274171445 )

Discussion to move from Coulomb to Ampere should be a separate issue.

I am leaning towards retaining radian (plane angle) as a base unit for the purpose of parsing and computing, for the reasons explained here: https://en.wikipedia.org/wiki/Radian

Christof