Struct peroxide::numerical::spline::CubicSpline

pub struct CubicSpline { /* private fields */ }

Cubic Spline (Natural)

Description

Implement traits of Natural cubic splines, by Arne Morten Kvarving.

Type

(&[f64], &[f64]) -> Cubic Spline

Examples

#[macro_use]
extern crate peroxide;
use peroxide::fuga::*;

fn main() -> Result<(), Box<dyn Error>> {
    let x = c!(0.9, 1.3, 1.9, 2.1);
    let y = c!(1.3, 1.5, 1.85, 2.1);

    let s = cubic_spline(&x, &y)?;

    let new_x = c!(1, 1.5, 2.0);

    // Generate Cubic polynomial
    for t in new_x.iter() {
        s.polynomial_at(*t).print();
    }
    // -0.2347x^3 + 0.6338x^2 - 0.0329x + 0.9873
    // 0.9096x^3 - 3.8292x^2 + 5.7691x - 1.5268
    // -2.2594x^3 + 14.2342x^2 - 28.5513x + 20.2094

    // Evaluation
    for t in new_x.iter() {
        s.eval(*t).print();
    }

    Ok(())
}

Implementations

impl CubicSpline

pub fn from_nodes(node_x: &[f64], node_y: &[f64]) -> Result<Self>

Examples

#[macro_use]
extern crate peroxide;
use peroxide::fuga::*;

fn main() -> Result<(), Box<dyn Error>> {
    let x = c!(0.9, 1.3, 1.9, 2.1);
    let y = c!(1.3, 1.5, 1.85, 2.1);

    let s = CubicSpline::from_nodes(&x, &y)?;

    for i in 0 .. 4 {
        println!("{}", s.eval(i as f64 / 2.0));
    }

    Ok(())
}

pub fn extend_with_nodes( &mut self, node_x: Vec<f64>, node_y: Vec<f64> ) -> Result<()>

Extends the spline with the given nodes.

Description

The method ensures that the transition between each polynomial is smooth and that the spline interpolation of the new nodes is calculated around x = 0 in order to avoid that successive spline extensions with large x values become inaccurate.

Trait Implementations

impl Calculus for CubicSpline

fn derivative(&self) -> Self

fn integral(&self) -> Self

fn integrate<T: Into<f64> + Copy>(&self, interval: (T, T)) -> f64

impl Clone for CubicSpline

fn clone(&self) -> CubicSpline

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for CubicSpline

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for CubicSpline

fn default() -> CubicSpline

Returns the “default value” for a type.

impl From<Vec<(Range<f64>, Polynomial)>> for CubicSpline

fn from(polynomials: Vec<(Range<f64>, Polynomial)>) -> Self

Converts to this type from the input type.

impl Index<usize> for CubicSpline

type Output = (Range<f64>, Polynomial)

The returned type after indexing.

fn index(&self, index: usize) -> &Self::Output

Performs the indexing (container[index]) operation.

impl Into<Vec<(Range<f64>, Polynomial)>> for CubicSpline

fn into(self) -> Vec<(Range<f64>, Polynomial)>

Converts this type into the (usually inferred) input type.

impl Into<Vec<Polynomial>> for CubicSpline

fn into(self) -> Vec<Polynomial>

Converts this type into the (usually inferred) input type.

impl Spline for CubicSpline

fn get_ranged_polynomials(&self) -> &Vec<(Range<f64>, Polynomial)>

fn eval<T: Into<f64> + Copy>(&self, x: T) -> f64

fn eval_vec<T: Into<f64> + Copy>(&self, v: &[T]) -> Vec<f64>

fn polynomial_at<T: Into<f64> + Copy>(&self, x: T) -> &Polynomial

fn number_of_polynomials(&self) -> usize

fn eval_with_cond<F: Fn(f64) -> f64>(&self, x: f64, cond: F) -> f64

fn eval_vec_with_cond<F: Fn(f64) -> f64 + Copy>( &self, x: &[f64], cond: F ) -> Vec<f64>