15 unstable releases (7 breaking)
new 0.8.0 | Apr 11, 2024 |
---|---|
0.7.0 | Oct 15, 2023 |
0.6.2 | Aug 6, 2023 |
0.6.0 | Jan 20, 2023 |
0.2.0 | Jul 26, 2021 |
#37 in Science
179 downloads per month
Used in 7 crates
115KB
2.5K
SLoC
quantity
Representation of quantities, i.e. of unit valued scalars and arrays. Rust library with Python bindings.
As opposed to other implementations, this crate does not attempt to achieve compile time checks on units. It is written with flexibility in mind and is able to represent arbitrarily complex units. Additional to simple scalar quantities, it also provides utilities for vector valued quantities, based on the ndarray crate, where all entries share the same unit.
Installation and Usage
Rust
Add this to your Cargo.toml
:
[dependencies]
quantity = "0.8"
Python package
Python bindings for the SI functionalities are published under the name si-units on PyPI.
Examples
Calculate pressure of an ideal gas.
let temperature = 25.0 * CELSIUS;
let volume = 1.5 * METER.powi(3);
let moles = 75.0 * MOL;
let pressure = moles * RGAS * temperature / volume;
println!("{:.5}", pressure); // 123.94785 kPa
Calculate the gravitational pull of the moon on the earth.
let mass_earth = 5.9724e24 * KILOGRAM;
let mass_moon = 7.346e22 * KILOGRAM;
let distance = 383.398 * KILO * METER;
let force = G * mass_earth * mass_moon / distance.powi(2);
println!("{:.5e}", force); // 1.99208e26 N
Calculate the pressure distribution in the atmosphere using the barometric formula.
let z = SIArray1::linspace(1.0 * METER, 70.0 * KILO * METER, 10)?;
let g = 9.81 * METER / SECOND.powi(2);
let m = 28.949 * GRAM / MOL;
let t = 10.0 * CELSIUS;
let p0 = BAR;
let pressure = p0 * (-&z * m * g).to_reduced(RGAS * t)?.mapv(f64::exp);
for i in 0..10 {
println!("z = {:8.5} p = {:9.5}", z.get(i), pressure.get(i));
}
// z = 1.00000 m p = 99.98794 kPa
// z = 7.77867 km p = 39.12796 kPa
// z = 15.55633 km p = 15.31182 kPa
// z = 23.33400 km p = 5.99192 kPa
// z = 31.11167 km p = 2.34480 kPa
// z = 38.88933 km p = 917.58301 Pa
// z = 46.66700 km p = 359.07479 Pa
// z = 54.44467 km p = 140.51557 Pa
// z = 62.22233 km p = 54.98750 Pa
// z = 70.00000 km p = 21.51808 Pa
Documentation
For the rust documentation, see here.
For the python documentation, see here.
Development
To build the project including the bindings to python, we use maturin.
When developing, use
maturin develop --release -m si-units/Cargo.toml
To build the python wheels, use
maturin build --release -m si-units/Cargo.toml
To build the documentation you need sphinx
and some additional packages. From the root directory, type
cd si-units/docs
make html
To run the doctests, from the root directory, type
cd si-units/docs
make doctest
Dependencies
~4–13MB
~125K SLoC