flag-algebra 0.4.0

An implementation of Razborov's flag algebras
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45

use approx::assert_relative_eq;
use flag_algebra::{
    tools::{SdpaCertificate, CERTIFICATE_FILE},
    *,
};
use flags::Graph;

fn make_goodman_problem() -> Problem<f64, Graph> {
    let basis = Basis::new(3);

    Problem {
        ineqs: vec![total_sum_is_one(basis), flags_are_nonnegative(basis)],
        cs: basis.all_cs(),
        obj: flag(&Graph::clique(3)) + flag(&Graph::empty(3)),
    }
}

#[test]
pub fn solve_with_csdp() {
    let problem = make_goodman_problem();

    let temp_dir = tempfile::tempdir().unwrap();
    let file = format!("{}/goodman_e2e", temp_dir.path().to_str().unwrap());
    assert_eq!(problem.solve_csdp(&file).unwrap(), 0.25);
}

#[test]
pub fn solve_and_read_certificate() {
    let problem = make_goodman_problem();

    let temp_dir = tempfile::tempdir().unwrap();
    let file = format!("{}/goodman_e2e", temp_dir.path().to_str().unwrap());

    problem.write_sdpa(&file).unwrap();
    problem.run_csdp(&file, None, false).unwrap();

    let certificate = SdpaCertificate::load(CERTIFICATE_FILE).unwrap();

    assert_relative_eq!(
        *certificate.y.as_slice(),
        [0.125, 0.375, 0.375, 0.125],
        epsilon = 0.00001
    );
    assert_eq!(certificate.coeffs.len(), 18);
}