bicubic

A base for bicubic interpolation

This projects provides the basis for bicubic interpolation. It is meant to allow any kind of interpolation.
If you need something ready to use check out the makima_spline::n_dimensional

HowTo

use bicubic;

create data

// x coordinates
let x = vec![-2.5, 0.0, 1.5];
// y coordinates
let y = vec![-4.5, 3.2];
// the value at (x,y) or z if that's how you see it
let f = vec![12.4, 1.45, 1.33, 13.4, 13.2, 6.];

// for simplicity, the next values are zero (the values depend on the type of interpolation used)
// first derivative along x direction for each point
let fx = vec![0.0; f.len()];
// first derivative along y direction for each point
let fy = vec![0.0; f.len()];
// cross derivative (untested)
let fxy = vec![0.0; f.len()];

The following image shows the layout of the data. fx, fy, & fxy is placed the same way as f

Note: x & y needs to be sorted in ascending order. Make sure your f values will swap indices when sorting as well

build the bicubic struct from the data

let bci = bicubic::from_vec(&x, &y, &f, &fx, &fy, &fxy);

To sample do this:

let z = bci.sample(x, y);