Struct Spline 

pub struct Spline<I, T> {
    pub interp: I,
    pub xa: Vec<T>,
    pub ya: Vec<T>,
    /* private fields */
}

1D Higher level interface.

A Spline owns the data it is constructed with, and provides the same evalulation methods as the lower-level Interpolator object, without needing to provide the data arrays in every call.

Example

let mut acc = Accelerator::new();

let xa = [0.0, 1.0, 2.0, 3.0, 4.0];
let ya = [0.0, 2.0, 4.0, 6.0, 8.0];

let interp = Cubic.build(&xa, &ya)?;

let typ = Cubic;
let spline = Spline::build(typ, &xa, &ya)?;

let x = 1.5;
let y_interp = interp.eval(&xa, &ya, x, &mut acc)?;
let y_spline = spline.eval(x, &mut acc)?;

assert_eq!(y_interp, y_spline);

Fields

interp: I

The lower-level Interpolator.

xa: Vec<T>

The owned x data.

ya: Vec<T>

The owned y data.

Implementations

impl<I, T> Spline<I, T>

where I: Interpolation<T>, T: Num + Lapack,

pub fn build( typ: impl InterpType<T, Interpolator = I>, xa: &[T], ya: &[T], ) -> Result<Self, InterpolationError>

Constructs a Spline of an Interpolation type typ from the data arrays xa and ya.

Example

let xa = [0.0, 1.0, 2.0, 3.0, 4.0];
let ya = [0.0, 2.0, 4.0, 6.0, 8.0];
let typ = Cubic;

let spline = Spline::build(typ, &xa, &ya)?;

pub fn eval(&self, x: T, acc: &mut Accelerator) -> Result<T, DomainError>

Returns the interpolated value y for a given point x, using the Accelerator acc.

Example

let mut acc = Accelerator::new();

let xa = [0.0, 1.0, 2.0, 3.0, 4.0];
let ya = [0.0, 2.0, 4.0, 6.0, 8.0];
let typ = Cubic;
let spline = Spline::build(typ, &xa, &ya)?;
let y = spline.eval(1.5, &mut acc)?;

assert_eq!(y, 3.0);

Errors

Returns a DomainError if x is outside the range of xa.

pub fn eval_deriv(&self, x: T, acc: &mut Accelerator) -> Result<T, DomainError>

Returns the derivative dy/dx of an interpolated function for a given point x, using the Accelerator acc.

Example

let mut acc = Accelerator::new();

let xa = [0.0, 1.0, 2.0, 3.0, 4.0];
let ya = [0.0, 2.0, 4.0, 6.0, 8.0];
let typ = Cubic;
let spline = Spline::build(typ, &xa, &ya)?;

let dydx = spline.eval_deriv(1.5, &mut acc)?;

assert_eq!(dydx, 2.0);

Errors

Returns a DomainError if x is outside the range of xa.

pub fn eval_deriv2(&self, x: T, acc: &mut Accelerator) -> Result<T, DomainError>

Returns the second derivative d²y/dx² of an interpolated function for a given point x, using the Accelerator acc.

Example

let mut acc = Accelerator::new();

let xa = [0.0, 1.0, 2.0, 3.0, 4.0];
let ya = [0.0, 2.0, 4.0, 6.0, 8.0];
let typ = Cubic;
let spline = Spline::build(typ, &xa, &ya)?;

let dydx = spline.eval_deriv2(1.5, &mut acc)?;

assert_eq!(dydx, 0.0);

Errors

Returns a DomainError if x is outside the range of xa.

pub fn eval_integ( &self, a: T, b: T, acc: &mut Accelerator, ) -> Result<T, DomainError>

Returns the numerical integral of an interpolated function over the range [a ,b], using the Accelerator acc.

Example

let mut acc = Accelerator::new();

let xa = [0.0, 1.0, 2.0, 3.0, 4.0];
let ya = [0.0, 2.0, 4.0, 6.0, 8.0];
let typ = Cubic;
let spline = Spline::build(typ, &xa, &ya)?;

let int = spline.eval_integ(0.0, 2.0, &mut acc)?;

assert_eq!(int, 4.0);

Errors

Returns a DomainError if a or b is outside the range of xa.

pub fn name(&self) -> String

Returns the name of the Interpolator.

pub fn min_size(&self) -> usize

Returns the minimum number of points required by the Interpolator.