2 releases
0.1.1 | Jun 29, 2019 |
---|---|
0.1.0 | Jun 28, 2019 |
#10 in #earth
32KB
748 lines
EMD
A simple Rust library for computing the Earth Mover's Distance (or "Wasserstein distance" or "Kantorovich–Rubinstein distance").
This is a wrapper of Gary Doran's pyemd.
Basic usage
Include the following in Cargo.toml
:
emd = "0.1.1"
Then:
extern crate emd;
#[macro_use(array)]
extern crate ndarray;
use emd::*;
use ndarray::*;
let x = array![0., 1.];
let y = array![5., 3.];
assert_eq!(distance(&x.view(), &y.view()), 3.5);
Check out the docs for more.
Maintainers
lib.rs
:
Earth Mover's Distance (EMD)
This is a wrapper around pyemd
[1] for computing the EMD (or Wasserstein)
metric.
By default, it uses Euclidean distance as a cost function, but this
can be changed by using the generic distance function distance_generic()
.
Examples
It allows computing the distance between two vectors (e.g., histograms):
extern crate emd;
#[macro_use(array)]
extern crate ndarray;
use emd::*;
use ndarray::*;
let x = array![0., 1.];
let y = array![5., 3.];
assert_eq!(distance(&x.view(), &y.view()), 3.5);
Or between matrices (e.g., multivariate histograms). Note that in this case the two matrices must have the same number of columns.
extern crate emd;
#[macro_use(array)]
extern crate ndarray;
use emd::*;
use ndarray::*;
let x = array![[4., 3.], [3., 6.], [2., 3.]];
let y = array![[2., 3.], [1., 3.]];
assert_eq!(distance_multi(&x.view(), &y.view()), 2.035183758487996);
Alternatively, one can compute EMD for matrices (and, by extension,
vectors) with a chosen distance as cost function by using
distance_generic()
.
References
Dependencies
~2MB
~42K SLoC