feat: initial otko import

tests/unit/test_phase9.py

@@ -0,0 +1,161 @@
+"""Unit tests for Phase 9 — Fiber sections + section properties."""
+
+from __future__ import annotations
+
+import math
+
+import numpy as np
+import pytest
+
+from otko.core import (
+    AggregatorDOF,
+    CircularPatch,
+    ElasticSection,
+    FiberSection,
+    Fibre,
+    Project,
+    RectangularPatch,
+    SectionAggregator,
+    StraightLayer,
+)
+from otko.services import load_project, save_project
+from otko.services.section_properties import (
+    compute_section_props,
+    expand_fibres,
+)
+
+
+# ── RectangularPatch ─────────────────────────────────────────────────
+def test_rectangular_patch_expands_to_correct_count() -> None:
+    sec = FiberSection(
+        id=1,
+        patches=[RectangularPatch(
+            material_id=1, n_fib_y=5, n_fib_z=4,
+            y_i=-0.1, z_i=-0.1, y_j=0.1, z_j=0.1,
+        )],
+    )
+    fibres = expand_fibres(sec)
+    assert fibres.shape == (20, 3)
+    # Total area = 0.2 × 0.2 = 0.04 m²
+    assert np.sum(fibres[:, 2]) == pytest.approx(0.04, rel=1e-9)
+
+
+def test_rectangular_patch_centroid_at_origin() -> None:
+    sec = FiberSection(
+        id=1,
+        patches=[RectangularPatch(
+            material_id=1, n_fib_y=8, n_fib_z=8,
+            y_i=-0.15, z_i=-0.15, y_j=0.15, z_j=0.15,
+        )],
+    )
+    props = compute_section_props(sec)
+    assert props.centroid_y == pytest.approx(0.0, abs=1e-12)
+    assert props.centroid_z == pytest.approx(0.0, abs=1e-12)
+
+
+# ── CircularPatch ────────────────────────────────────────────────────
+def test_circular_patch_area_approaches_pi_r_squared() -> None:
+    r = 0.15
+    sec = FiberSection(
+        id=1,
+        patches=[CircularPatch(
+            material_id=1, n_fib_circ=32, n_fib_rad=8,
+            r_inner=0.0, r_outer=r,
+        )],
+    )
+    props = compute_section_props(sec)
+    expected = math.pi * r ** 2
+    # With 32×8 = 256 fibres, area should be close (within ~1%).
+    assert props.area == pytest.approx(expected, rel=0.01)
+    assert props.centroid_y == pytest.approx(0.0, abs=1e-6)
+    assert props.centroid_z == pytest.approx(0.0, abs=1e-6)
+
+
+# ── StraightLayer ───────────────────────────────────────────────────
+def test_straight_layer_expands_correctly() -> None:
+    sec = FiberSection(
+        id=1,
+        layers=[StraightLayer(
+            material_id=2, n_bars=4, bar_area=0.0005,
+            y_start=-0.1, z_start=-0.12,
+            y_end=0.1, z_end=-0.12,
+        )],
+    )
+    fibres = expand_fibres(sec)
+    assert fibres.shape == (4, 3)
+    assert np.sum(fibres[:, 2]) == pytest.approx(0.002)
+    # All z coordinates should be -0.12 (horizontal layer).
+    np.testing.assert_array_almost_equal(fibres[:, 1], -0.12)
+
+
+# ── SectionAggregator ───────────────────────────────────────────────
+def test_section_aggregator_schema() -> None:
+    agg = SectionAggregator(
+        id=5, name="Fiber+Torsion",
+        section_id=1,
+        pairings=[AggregatorDOF(material_id=3, dof="T")],
+    )
+    assert agg.type == "SectionAggregator"
+    assert agg.pairings[0].dof == "T"
+
+
+# ── Mixed section → Iy / Iz ─────────────────────────────────────────
+def test_Iz_of_rect_matches_analytical() -> None:
+    """Iz = b·h³/12 for a rectangle centred at origin."""
+    b, h = 0.3, 0.5   # y-range: -0.15..0.15, z-range: -0.25..0.25
+    sec = FiberSection(
+        id=1,
+        patches=[RectangularPatch(
+            material_id=1, n_fib_y=20, n_fib_z=20,
+            y_i=-b / 2, z_i=-h / 2, y_j=b / 2, z_j=h / 2,
+        )],
+    )
+    props = compute_section_props(sec)
+    # Iz = about z-axis = b·h³/12? No — our convention:
+    #   Iz = Σ A_i · (y_i - ȳ)²  (second moment about the z-axis).
+    # For rect: Iz = h·b³/12.
+    Iz_exact = h * b ** 3 / 12.0
+    Iy_exact = b * h ** 3 / 12.0
+    assert props.Iz == pytest.approx(Iz_exact, rel=0.01)
+    assert props.Iy == pytest.approx(Iy_exact, rel=0.01)
+
+
+# ── Round-trip persistence ───────────────────────────────────────────
+def test_fiber_section_with_patches_round_trips(tmp_path) -> None:  # type: ignore[no-untyped-def]
+    from otko.core import Node, ElasticBeamColumn
+    p = Project(
+        nodes=[Node(id=1, coords=(0, 0, 0)), Node(id=2, coords=(1, 0, 0))],
+        sections=[
+            FiberSection(
+                id=1, name="RC-Beam",
+                patches=[RectangularPatch(
+                    material_id=1, n_fib_y=4, n_fib_z=4,
+                    y_i=-0.15, z_i=-0.25, y_j=0.15, z_j=0.25,
+                )],
+                layers=[StraightLayer(
+                    material_id=2, n_bars=3, bar_area=0.0005,
+                    y_start=-0.12, z_start=-0.22,
+                    y_end=0.12, z_end=-0.22,
+                )],
+            ),
+            SectionAggregator(
+                id=2, name="Agg", section_id=1,
+                pairings=[AggregatorDOF(material_id=3, dof="T")],
+            ),
+        ],
+        elements=[ElasticBeamColumn(
+            id=1, nodes=(1, 2), section_id=1,
+        )],
+    )
+    path = tmp_path / "fib.osmodel"
+    save_project(p, path)
+    r = load_project(path)
+    fs = r.sections[0]
+    assert isinstance(fs, FiberSection)
+    assert len(fs.patches) == 1
+    assert fs.patches[0].kind == "rect"
+    assert len(fs.layers) == 1
+    assert fs.layers[0].n_bars == 3
+    agg = r.sections[1]
+    assert isinstance(agg, SectionAggregator)
+    assert agg.pairings[0].dof == "T"