Struct CubicSpline 

pub struct CubicSpline { /* private fields */ }

Natural cubic spline interpolation.

Constructs a smooth curve through data points using piecewise cubic polynomials with continuous first and second derivatives.

“Natural” means the second derivative is zero at the endpoints.

Example

use convex_math::interpolation::{CubicSpline, Interpolator};

let xs = vec![0.0, 1.0, 2.0, 3.0];
let ys = vec![0.0, 1.0, 4.0, 9.0];

let spline = CubicSpline::new(xs, ys).unwrap();
let y = spline.interpolate(1.5).unwrap();

Implementations

impl CubicSpline

pub fn new(xs: Vec<f64>, ys: Vec<f64>) -> MathResult<Self>

Creates a natural cubic spline interpolator.

Arguments

• xs - X coordinates (must be sorted in ascending order)
• ys - Y coordinates

Errors

Returns an error if there are fewer than 3 points or if lengths differ.

pub fn with_extrapolation(self) -> Self

Enables extrapolation beyond the data range.

Trait Implementations

impl Clone for CubicSpline

fn clone(&self) -> CubicSpline

Returns a duplicate 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 Interpolator for CubicSpline

fn interpolate(&self, x: f64) -> MathResult<f64>

Returns the interpolated value at x.

fn derivative(&self, x: f64) -> MathResult<f64>

Returns the first derivative at x.

fn allows_extrapolation(&self) -> bool

Returns true if extrapolation is allowed.

fn min_x(&self) -> f64

Returns the minimum x value in the data.

fn max_x(&self) -> f64

Returns the maximum x value in the data.

fn in_range(&self, x: f64) -> bool

Checks if x is within the interpolation range.