# vincenty-core

Calculate distances between two coordinates using vincenty formulae.

## Overview

This Rust module provides functions for calculating the geodesic distance
between two points specified by latitude/longitude on the surface of an
ellipsoid. The computation is based on the Vincenty's formulae, known for their
high accuracy.

Features:

- High Precision: The module is designed to return results with a precision of
  up to 6 decimal places.

- Custom Error Handling: The module uses Rust's Result type for error handling,
  ensuring that any issues during computation are handled gracefully and
  informatively.

- Convenient Input Types: The module provides two functions for distance
  calculation that accept different input types: one takes
  `geo_types::geometry::Coord` objects, and the other takes points as `f64`
  parameters directly.

## Usage

Add the module to your Rust project and use it as follows:

```rust
use geo_types::geometry::Coord;
use vincenty_core::{distance_from_coords, distance_from_points};

let x1 = 40.712776;
let y1 = -74.005974;
let x2 = 34.052235;
let y2 = -118.243683;
let coord1 = Coord { x: x1, y: y1 };
let coord2 = Coord { x: x2, y: y2 };

let distance1 = distance_from_coordinates(&coord1, &coord2);
let distance2 = distance_from_points(x1, y1, x2, y2);
assert_eq!(distance1, distance2);
```

## Testing

The module includes unit tests for its main functions. To run these tests, use
the following command:

```bash
$ cargo test
```

## Limitations

Please note that the algorithm performs a maximum of 200 iterations to find a
result within a specified threshold `1e-9`. If the algorithm fails to converge
within these iterations, an error is returned.

## Contributing

Feel free to fork this module and submit pull requests for any enhancements or
bug fixes. Make sure to include unit tests for any new functionality.

## License

This module is available under the MIT License.