bacon-sci 0.16.2

Scientific computing in Rust
Documentation 
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/* This file is part of bacon.
 * Copyright (c) Wyatt Campbell.
 *
 * See repository LICENSE for information.
 */

use crate::interp::{hermite, lagrange};
use crate::polynomial::Polynomial;

mod spline;

#[test]
fn lagrange_interp() {
    let xs: Vec<_> = (0..10).map(|i| i as f64).collect();
    let ys: Vec<_> = xs.iter().map(|x| x.cos()).collect();

    let poly = lagrange(&xs, &ys, 1e-6).unwrap();
    // Test rebuilding a Polynomial
    let rebuilt_poly = Polynomial::from_slice(&poly.get_coefficients());

    for x in xs {
        println!("{} {}", poly.evaluate(x), x.cos());
        assert!(approx_eq!(
            f64,
            poly.evaluate(x),
            x.cos(),
            epsilon = 0.00001
        ));
        assert!(approx_eq!(
            f64,
            rebuilt_poly.evaluate(x),
            x.cos(),
            epsilon = 0.00001
        ));
    }

    for x in 0..=100 {
        let x = x as f64 * 0.1;
        assert!(approx_eq!(f64, poly.evaluate(x), x.cos(), epsilon = 0.5));
    }
}

#[test]
fn hermite_interp() {
    let xs: Vec<_> = (0..5).map(|i| i as f64).collect();
    let ys: Vec<_> = xs.iter().map(|x| x.cos()).collect();
    let derivs: Vec<_> = xs.iter().map(|x| -x.sin()).collect();

    let poly = hermite(&xs, &ys, &derivs, 1e-6).unwrap();

    for x in xs {
        let (p, deriv) = poly.evaluate_derivative(x);
        assert!(approx_eq!(f64, p, x.cos(), epsilon = 0.0000001));
        assert!(approx_eq!(f64, deriv, -x.sin(), epsilon = 0.0000001));
    }
}