splinify 0.2.2

Rust-wrapper for Dierckx' B-Splines Curve and Surface Fortran Library
Documentation 
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use splinify::{ClosedCubicSplineFit2D, Result, SplineCurveData};

fn ellipse(t: f64, a: f64, b: f64) -> [f64; 2] {
    [a * t.cos(), b * t.sin()]
}

fn main() -> Result<()> {
    let example_dir = std::path::Path::new(env!("CARGO_MANIFEST_DIR"))
        .join(std::path::Path::new(file!()).parent().unwrap());

    let n_points = 1000;
    let mut u: Vec<f64> = (0..n_points).map(|i| i as f64 / n_points as f64).collect();
    let mut xy: Vec<f64> = u
        .iter()
        .flat_map(|&t| ellipse(t * std::f64::consts::TAU, 2.0, 1.0))
        .collect();

    // Close the curve: append first point with u = 1.0
    xy.extend([xy[0], xy[1]]);
    u.push(1.0);

    let d = ClosedCubicSplineFit2D::new(u, xy)?.smoothing_spline(1E-6)?;

    let json = serde_json::to_string_pretty(&SplineCurveData::from(&d))?;
    println!("{}", json);

    let plot_path = example_dir.join("fit.png");
    d.plot(plot_path.to_str().expect("non-UTF-8 path"), (2000, 1000))?;

    Ok(())
}