Module dimensioned::unit_systems [] [src]

Predefined unit systems

When it makes sense, conversions are defined between unit systems. See the conversion module for more information.


Each unit system contained herein lists in tables its base units, derived units, and constants.

Each item in the "Constant" column is the name of a constant created in both the f32consts and f64consts submodules. Everything in the f64consts submodule is also re-exported in the unit system module for ease of use.

Each item in the "Unit" column is the name of a type alias for that unit in the unit system. It needs to be parametrized to be used.

For example, in the SI system, there is a defined unit Meter with accompanying constant M. We can use them as follows.

extern crate dimensioned as dim;
use dim::si::{self, Meter, M};

fn main() {
    let x: Meter<f64> = 3.0 * M;
    let y = Meter::new(3.0);
    let z = 3.0 * M;

    assert_eq!(x, y);
    assert_eq!(x, z);

    let x32: Meter<f32> = 3.0 * si::f32consts::M;
    let y32 = Meter::new(3.0);

    assert_eq!(x32, y32);

Naming conventions

When a unit has a proper name, we use that. When it does not, we use the following naming convention:

For the type definition of a derived unit, the name will all of the units in the numerator listed, each followed by the number of its power, and then, if there are units in the denominator, the word Per and all of the units in the denominator.

The accompanying constants follow a similar convention, but use the constant instead of unit name and the letter P instead of Per.

For example, we define MeterPerSecond2 for acceleration in the SI system, with the accompanying constant MPS2.


Note that the unit systems included here should not be considered complete. New units and systems will be added. If there are any particular units or unit systems that you think should be added, please submit an issue on github.

All of these unit systems were generated using the make_units! macro. See its documentation for more information.



The Gaussian CGS unit system


The foot, pound, second system, using the mass pound as a base unit.


The Gaussian MKS unit system


The International System of Units (SI)


The Unified Code for Units of Measure (UCUM)