Ability to define other unit conversion systems

[simoami]

Hello, I'm using mathjs for a medical application which uses Conventional Units over SI (e.g. Celsius for temperature over Kelvin and mmHg for blood pressure, instead of Pa, Bar or kg / (m s^2)). See example Lab unit tables:
https://www.labcorp.com/resource/si-unit-conversion-table
https://connect.springerpub.com/content/book/978-0-8261-0976-7/back-matter/app2
https://www.cmeinfo.com/wp-content/uploads/2021/09/0.-Laboratory-Units-Conversion-Table.pdf

Is there a way to customize the behavior for another system? For example, allow users to define a series of methods similar to .toSI(), such as toImperial(), .toMetric(), .toMedical()...etc.

[josdejong]

Thanks for your suggestion. It would be nice indeed to have more control over the type of unit system used to simplify the units. This should be addressed by UnitMath, which we want to integrate in mathjs (replacing the build in Unit class), see the docs of UnitMath about simplify, for example:

unit('8 kg m / s^2').simplify({ system: 'si' })

See:

• Set unitSystem conversion #1282
• Configurable unit formatting #2738