Struct InternalFunction 

pub struct InternalFunction {
    pub grid: Vec<f64>,
    pub values: Vec<f64>,
}

An internal function approximation: a function on a hyperfinite grid.

Fields

grid: Vec<f64>

Grid points (as f64 for computability).

values: Vec<f64>

Function values at each grid point.

Implementations

impl InternalFunction

pub fn new(grid: Vec<f64>, values: Vec<f64>) -> Self

Create an internal function from a grid and corresponding values.

pub fn from_fn<F: Fn(f64) -> f64>(grid: Vec<f64>, f: F) -> Self

Sample the function from a standard function on the grid.

pub fn eval_nearest(&self, x: f64) -> f64

Evaluate (nearest-grid-point interpolation) at a point x.

pub fn ns_derivative_at(&self, i: usize) -> f64

Compute the nonstandard derivative at grid point i (finite difference).

pub fn riemann_sum(&self) -> f64

Compute the internal Riemann sum ∑ f(xᵢ) Δxᵢ.