flare 0.2.0

A lightweight library to perform basic astronomical calculations, inspired by Python's Astropy syntax.
Documentation 
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/// Calculate the refraction correction for a given true altitude.
///
/// # Arguments
///
/// * `h` - True altitude in degrees.
///
/// # Returns
///
/// * The refraction correction in degrees.
///
/// # Example
///
/// ```
/// use flare::corrections::refraction;
///
/// let h = 0.5541;
/// let r = refraction(h);
/// println!("Refraction correction: {:.4} degrees", r);
/// assert!((r - 0.410302).abs() < 1.0e-6);
/// ```
///
/// # References
/// formula 16.4 of "Astronomical Algorithms" 2nd edition by Jean Meeus (Willmann-Bell, Richmond) 1998.
/// 1.02 / tan(h + 10.3 / (h + 5.11)) h in degrees, result in arc minutes
pub fn refraction(h: f64) -> f64 {
    if h < 0.0 {
        return 0.0;
    }

    (1.02 / (h + (10.3 / (h + 5.11))).to_radians().tan()) / 60.0
}