# donnager.rs

A library of functions for blazingly fast astrodynamic calculations. 

Until the rains fall on Olympus Mons.


---
Note: Under active development, updating structure frequently.

Stable release TBD
---


## Installation
```
cargo install donnager
```

or, alternatively, in your project's `cargo.toml` file:

```
[dependencies]
donnager = "0.1.2"
```

## Modules
- `cosmos`
- `dynamics`
- `propulsion`

## Example Usage

```Rust
use donnager::constants as cst;
use donnager::cosmos as cosm;
use donnager::propulsion as prop;
use donnager::dynamics as dynam;

use nalgebra as na;
use na::Vector3;

// Config
let earth: cosm::gravity::Body = cosm::gravity::Body {
    name: "Earth".to_string(),
    grav_param: cst::EARTH_GRAV_PARAM,
    eq_radius: cst::EARTH_RADIUS_EQUATOR,
    rotation_rate: cst::EARTH_ROT_RATE,
    eccentricity: cst::EARTH_ECC
};

let launch_site: cosm::space::SurfacePoint = cosm::space::SurfacePoint {
    name: "Cape Canaveral Launch Site".to_string(),
    body: earth.clone(),
    pos_lla: Vector3::new(28.396837, -80.605659, 0.0)
};

let payload_eng: prop::engine::Engine = prop::engine::Engine{
    name: "Payload_Engine".to_string(),
    engine_type: prop::engine::EngineType::Electric,
    isp: 500.0
};

let payload: dynam::vehicle::Vehicle = dynam::vehicle::Vehicle {
    name: "Satellite_1".to_string(),
    mass: 5.0,
    engine: payload_eng
};

let stage1_eng: prop::engine::Engine = prop::engine::Engine{
    name: "Hydrolox Dual Flow".to_string(),
    engine_type: prop::engine::EngineType::Chemical,
    isp: 300.0
};

let stage_1: dynam::vehicle::Vehicle = dynam::vehicle::Vehicle {
    name: "Stage_1".to_string(),
    mass: 250.0, 
    engine: stage1_eng
};

let launch_vehicle: dynam::vehicle::Multistage = dynam::vehicle::Multistage{
    name: "Launcher_7".to_string(),
    stages: [stage_1, payload].to_vec()
};

// Inputs
let altitude: f64 = 408000.0;  // LEO

// Calculation
let delta_v: f64 = launch_site.calc_delta_v(altitude);
let mass_fuel: Vec<f64> = launch_vehicle.calc_mass_fuel(delta_v, launch_site);

// Results
println!("\n{:.4} kg of fuel to get {} kg to {} m alt", mass_fuel[0], launch_vehicle.stages[1].mass, altitude);
    
```

Ad astra, plus ultra