mesh-sieve 4.0.1

Modular, high-performance Rust library for mesh and data management, designed for scientific computing and PDE codes.
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
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150

use mesh_sieve::adapt::{MetricAdaptationAction, MetricTensor, MetricThresholds};
use mesh_sieve::data::atlas::Atlas;
use mesh_sieve::data::coordinates::Coordinates;
use mesh_sieve::data::section::Section;
use mesh_sieve::data::storage::VecStorage;
use mesh_sieve::dm::{MeshDM, MeshDMMetricAdaptOptions, MeshDMTransferStrategy};
use mesh_sieve::io::MeshData;
use mesh_sieve::topology::Sieve;
use mesh_sieve::topology::cell_type::CellType;
use mesh_sieve::topology::labels::LabelSet;
use mesh_sieve::topology::point::PointId;
use mesh_sieve::topology::sieve::MeshSieve;

fn pt(id: u64) -> PointId {
    PointId::new(id).unwrap()
}

fn single_triangle_dm() -> (
    MeshDM<f64>,
    Section<MetricTensor, VecStorage<MetricTensor>>,
    PointId,
) {
    let mut sieve = MeshSieve::default();
    let cell = pt(10);
    let vertices = [pt(1), pt(2), pt(3)];
    for v in vertices {
        sieve.add_arrow(cell, v, ());
    }

    let mut coord_atlas = Atlas::default();
    for v in vertices {
        coord_atlas.try_insert(v, 2).unwrap();
    }
    let mut coords = Coordinates::<f64, VecStorage<f64>>::try_new(2, 2, coord_atlas).unwrap();
    coords
        .try_restrict_mut(vertices[0])
        .unwrap()
        .copy_from_slice(&[0.0, 0.0]);
    coords
        .try_restrict_mut(vertices[1])
        .unwrap()
        .copy_from_slice(&[3.0, 0.0]);
    coords
        .try_restrict_mut(vertices[2])
        .unwrap()
        .copy_from_slice(&[0.0, 1.0]);

    let mut cell_atlas = Atlas::default();
    cell_atlas.try_insert(cell, 1).unwrap();
    let mut cell_types = Section::<CellType, VecStorage<CellType>>::new(cell_atlas.clone());
    cell_types.try_set(cell, &[CellType::Triangle]).unwrap();

    let mut solution = Section::<f64, VecStorage<f64>>::new(cell_atlas.clone());
    solution.try_set(cell, &[42.0]).unwrap();

    let mut labels = LabelSet::new();
    labels.set_label(cell, "material", 7);

    let mesh_data = MeshData {
        sieve,
        coordinates: Some(coords),
        sections: [("solution".to_string(), solution)].into_iter().collect(),
        mixed_sections: Default::default(),
        labels: Some(labels),
        cell_types: Some(cell_types),
        discretization: None,
    };

    let mut metric = Section::<MetricTensor, VecStorage<MetricTensor>>::new(cell_atlas);
    metric
        .try_set(cell, &[MetricTensor::new_2d(1.0, 1.0, 0.0)])
        .unwrap();

    (MeshDM::<f64>::from_mesh_data(mesh_data), metric, cell)
}

#[test]
fn dm_metric_refinement_transfers_metadata_with_provenance() {
    let (mut dm, metric, cell) = single_triangle_dm();
    let mut options = MeshDMMetricAdaptOptions::default();
    options.transfer = MeshDMTransferStrategy::PreserveAll;
    options.thresholds = MetricThresholds {
        refine_max_edge_length: 2.0,
        coarsen_max_edge_length: 0.1,
        split_edge_length: 2.0,
        split_face_length: 2.0,
        check_geometry: false,
    };

    let result = dm
        .adapt_with_attached_metric("metric", &metric, |_| Vec::new(), options)
        .unwrap();

    assert!(matches!(
        result.action,
        MetricAdaptationAction::Refined { .. }
    ));
    assert_eq!(result.provenance.old_to_new.len(), 1);
    assert_eq!(result.provenance.old_to_new[0].0, cell);
    assert!(result.diagnostics.provenance_edges >= 4);
    assert_eq!(result.diagnostics.transferred_sections, 1);

    let fine_cells = &result.provenance.old_to_new[0].1;
    let solution = dm.section("solution").expect("transferred section");
    let labels = dm.labels().expect("transferred labels");
    let cell_types = dm.cell_types().expect("transferred cell types");
    for fine in fine_cells {
        assert_eq!(solution.try_restrict(*fine).unwrap(), &[42.0]);
        assert_eq!(labels.get_label(*fine, "material"), Some(7));
        assert_eq!(
            cell_types.try_restrict(*fine).unwrap(),
            &[CellType::Triangle]
        );
    }
    assert!(dm.coordinates().unwrap().section().iter().count() > 3);
}

#[test]
fn dm_metric_iterative_nochange_converges_and_keeps_metadata_stable() {
    let (mut dm, metric, cell) = single_triangle_dm();
    let mut options = MeshDMMetricAdaptOptions::default();
    options.transfer = MeshDMTransferStrategy::PreserveAll;
    options.thresholds = MetricThresholds {
        refine_max_edge_length: 10.0,
        coarsen_max_edge_length: 0.0,
        ..MetricThresholds::default()
    };

    let history = dm
        .adapt_with_attached_metric_iterative(
            "metric",
            &metric,
            |_| Vec::new(),
            options,
            3,
            |_| false,
        )
        .unwrap();

    assert_eq!(history.len(), 1);
    assert!(matches!(
        history[0].action,
        MetricAdaptationAction::NoChange
    ));
    assert_eq!(dm.labels().unwrap().get_label(cell, "material"), Some(7));
    assert_eq!(
        dm.section("solution").unwrap().try_restrict(cell).unwrap(),
        &[42.0]
    );
}