howzat

Dynamic double-description and LRS-backed conversion for convex cones and polytopes. Small API, pluggable numeric backends, and state-of-the-art performance.

Features

• DD + LRS backed: Select fast exact/inexact DD and exact LRS backends for conversion via one API.
• Cone/polytope primitives: Adjacency queries, tableau-based convex hull routines.
• Backend-agnostic: Works with rug (GMP) or dashu (pure-Rust) arbitrary precision (or neither).

Related crates

• howzat-kit: a higher-level runner API that selects common backends via a string backend spec.

Example

use howzat::prelude::*;

fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Triangle with vertices (0,0), (1,0), (0,1) in homogeneous generator form [1, x, y].
    let generators = vec![vec![1.0, 0.0, 0.0], vec![1.0, 1.0, 0.0], vec![1.0, 0.0, 1.0]];
    let matrix = LpMatrixBuilder::<f64, Generator>::from_rows(generators).build();
    let eps = f64::default_eps();

    let poly = PolyhedronOutput::<f64, Generator>::builder(matrix)
        .cone_options(ConeOptions::default())
        .polyhedron_options(PolyhedronOptions {
            output_incidence: IncidenceOutput::Set,
            output_adjacency: AdjacencyOutput::List,
            ..Default::default()
        })
        .run_dd_with_eps(eps)?;

    assert_eq!(poly.output().representation(), RepresentationKind::Inequality);
    assert!(poly.adjacency().is_some());
    Ok(())
}

License

AGPL-3.0-only. See LICENSE for details.