# sprs, sparse matrices for Rust

sprs implements some sparse matrix data structures and linear algebra algorithms in pure Rust.

The API is a work in progress, and feedback on its rough edges is highly appreciated :)

## Features

### Structures

- CSR/CSC matrix
- triplet matrix
- Sparse vector

### Operations

- sparse matrix / sparse vector product
- sparse matrix / sparse matrix product
- sparse matrix / sparse matrix addition, subtraction
- sparse vector / sparse vector addition, subtraction, dot product
- sparse/dense matrix operations

### Algorithms

- Outer iterator on compressed sparse matrices
- sparse vector iteration
- sparse vectors joint non zero iterations
- simple sparse Cholesky decomposition (requires opting into an LGPL license)
- sparse triangular solves with dense right-hand side

## Examples

Matrix construction

```
use sprs::{CsMat, CsMatOwned, CsVec};
let eye : CsMatOwned<f64> = CsMat::eye(3);
let a = CsMat::new_csc((3, 3),
vec![0, 2, 4, 5],
vec![0, 1, 0, 2, 2],
vec![1., 2., 3., 4., 5.]);
```

Matrix vector multiplication

```
use sprs::{CsMat, CsVec};
let eye = CsMat::eye(5);
let x = CsVec::new(5, vec![0, 2, 4], vec![1., 2., 3.]);
let y = &eye * &x;
assert_eq!(x, y);
```

Matrix matrix multiplication, addition

```
use sprs::{CsMat, CsVec};
let eye = CsMat::eye(3);
let a = CsMat::new_csc((3, 3),
vec![0, 2, 4, 5],
vec![0, 1, 0, 2, 2],
vec![1., 2., 3., 4., 5.]);
let b = &eye * &a;
assert_eq!(a, b.to_csr());
```

For a more complete example, be sure to check out the heat diffusion example.

## Documentation

Documentation is available at docs.rs.

## Changelog

See the changelog.

## Minimum Supported Rust Version

The minimum supported Rust version currently is 1.49. Prior to a 1.0 version, bumping the MSRV will not be considered a breaking change, but breakage will be avoided on a best effort basis.

## License

Licensed under either of

- Apache License, Version 2.0, (LICENSE-APACHE or https://www.apache.org/licenses/LICENSE-2.0)
- MIT license (LICENSE-MIT or https://opensource.org/licenses/MIT)

at your option.

### Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.

Please see the contribution guidelines for additional information about contributing.