Crate ndarray_interp

Source

Expand description

The ndarray-interp crate provides interpolation algorithms for interpolating n-dimesional data.

§1D Interpolation

The interp1d module provides the Interp1D interpolator and different interpolation strategies

1D Strategies

interp1d::Linear - Linear interpolation and extrapolation
interp1d::cubic_spline - Cubic Spline interpolation with different boundary conditions.

§2D Interpolation

The interp2d module provides the Interp2D interpolator and different interpolation strategies

2D Strategies

interp2d::Bilinear - Bilinear interpolation and extrapolation

§Custom interpolation strategy

This crate defines traits to allow implementation of user defined interpolation algorithms. A 1D interpolation strategy can be created by implementing the Interp1DStrategy and Interp1DStrategyBuilder traits. A 2D interpolation strategy can be created by implementing the Interp2DStrategy and Interp2DStrategyBuilder traits.

See also the custom_strategy.rs example.

§Examples

1D Example

use ndarray_interp::interp1d::*;
use ndarray::*;

let data = array![0.0, 1.0, 1.5, 1.0, 0.0 ];
let interp = Interp1DBuilder::new(data).build().unwrap();

let result = interp.interp_scalar(3.5).unwrap();
assert!(result == 0.5);
let result = interp.interp_array(&array![0.0, 0.5, 1.5]).unwrap();
assert!(result == array![0.0, 0.5, 1.25])

1D Example with multidimensional data

use ndarray_interp::interp1d::*;
use ndarray::*;

let data = array![
    [0.0, 1.0],
    [1.0, 2.0],
    [1.5, 2.5],
    [1.0, 2.0],
];
let x = array![1.0, 2.0, 3.0, 4.0];

let interp = Interp1D::builder(data)
    .strategy(Linear::new().extrapolate(true))
    .x(x)
    .build().unwrap();

let result = interp.interp(0.5).unwrap();
assert!(result == array![-0.5, 0.5]);
let result = interp.interp_array(&array![0.5, 4.0]).unwrap();
assert!(result == array![[-0.5, 0.5], [1.0, 2.0]]);

2D Example

use ndarray_interp::interp2d::*;
use ndarray::*;

let data = array![
    [1.0, 2.0, 2.5],
    [3.0, 4.0, 3.5],
];
let interp = Interp2D::builder(data).build().unwrap();

let result = interp.interp_scalar(0.0, 0.5).unwrap();
assert!(result == 1.5);
let result = interp.interp_array(&array![0.0, 1.0], &array![0.5, 2.0]).unwrap();
assert!(result == array![1.5, 3.5]);