Crate ndarray_parallel

Parallelization features for ndarray.

The array views and references to owned arrays all implement NdarrayIntoParallelIterator (*); the default parallel iterators (each element by reference or mutable reference) have no ordering guarantee in their parallel implementations.

.axis_iter() and .axis_iter_mut() also have parallel counterparts.

(*) This regime of a custom trait instead of rayon’s own is since we use this intermediate ndarray-parallel crate.

Examples

Compute the exponential of each element in an array, parallelized.

extern crate ndarray;
extern crate ndarray_parallel;

use ndarray::Array2;
use ndarray_parallel::prelude::*;

fn main() {
    let mut a = Array2::<f64>::zeros((128, 128));
    a.par_iter_mut().for_each(|x| *x = x.exp());
}

Use the parallel .axis_iter() to compute the sum of each row.

extern crate ndarray;
extern crate ndarray_parallel;

use ndarray::Array;
use ndarray::Axis;
use ndarray_parallel::prelude::*;

fn main() {
    let a = Array::linspace(0., 63., 64).into_shape((4, 16)).unwrap();
    let mut sums = Vec::new();
    a.axis_iter(Axis(0))
     .into_par_iter()
     .map(|row| row.scalar_sum())
     .collect_into(&mut sums);

    assert_eq!(sums, [120., 376., 632., 888.]);
}

Modules

prelude

Into- traits for creating parallelized iterators.

Structs

Parallel

Parallel iterator wrapper.

Traits

NdarrayIntoParallelIterator
NdarrayIntoParallelRefIterator
NdarrayIntoParallelRefMutIterator