Add physical-plane FEM model slice diagnostics and plots

experiments/test_plot_model_slices.py

@@ -0,0 +1,103 @@
+#!/usr/bin/env python3
+"""Small schema/plot controls; these are not stellar-equilibrium validation."""
+import csv
+from pathlib import Path
+import tempfile
+import unittest
+
+import matplotlib.pyplot as plt
+import numpy as np
+
+import plot_model_slices as slices
+
+
+def write_csv(path, header, rows):
+    with path.open("w", newline="") as stream:
+        writer = csv.writer(stream)
+        writer.writerow(header)
+        writer.writerows(rows)
+
+
+def fixture(directory):
+    # Two disconnected material triangles leave a genuine empty gap. Their
+    # enthalpy is independent of density and one density sample is negative.
+    coordinates = [(-2, 0), (-1, 0), (-1.5, 1), (1, 0), (2, 0), (1.5, 1)]
+    rho, h = [-.4, .2, 1, .5, 1, 2], [1, 2, 3, 4, 5, 6]
+    vertices = [[i, i // 3, u, .2, v, rho[i], h[i], 0] for i, (u, v) in enumerate(coordinates)]
+    write_csv(directory / "vertices.csv", ["vertex", "element", "x", "y", "z", "rho", "h", "plane_error"], vertices)
+    write_csv(directory / "triangles.csv", ["triangle", "element", "v0", "v1", "v2"], [[0, 0, 0, 1, 2], [1, 1, 3, 4, 5]])
+    segments = []
+    for element in range(2):
+        for i, j in ((0, 1), (1, 2), (2, 0)):
+            a, b = coordinates[3 * element + i], coordinates[3 * element + j]
+            segments.append([a[0], .2, a[1], b[0], .2, b[1], 0])
+    for name in ("surface.csv", "reference_surface.csv"):
+        write_csv(directory / name, ["x0", "y0", "z0", "x1", "y1", "z1", "maximum_plane_error"], segments)
+    metadata = dict(plane="xz", horizontal_axis=0, vertical_axis=2, normal_axis=1, offset=.2,
+                    root_tolerance=1e-11, deformation_scale=1, vertex_count=6, triangle_count=2,
+                    surface_segments=6, reference_surface_segments=6, surface_coplanar_triangles=0,
+                    reference_surface_coplanar_triangles=0, subdivisions=6, u_min=-2, u_max=2, v_min=0, v_max=1)
+    write_csv(directory / "metadata.csv", ["metric", "value"], metadata.items())
+
+
+class ModelSlicePlotTests(unittest.TestCase):
+    def setUp(self):
+        self.temporary = tempfile.TemporaryDirectory()
+        self.directory = Path(self.temporary.name)
+        fixture(self.directory)
+
+    def tearDown(self):
+        plt.close("all")
+        self.temporary.cleanup()
+
+    def test_signed_independent_fields_are_preserved(self):
+        data = slices.load_slice(self.directory)
+        self.assertEqual(data.vertices[0, 5], -.4)
+        self.assertEqual(data.vertices[0, 6], 1.)
+        norm, _, _ = slices.color_scale(data.vertices[:, 5])
+        self.assertEqual(norm(0.), .5)
+        self.assertEqual(norm(-.4), 0.)
+
+    def test_no_triangulation_across_vacuum(self):
+        data = slices.load_slice(self.directory)
+        np.testing.assert_array_equal(data.triangles, [[0, 1, 2], [3, 4, 5]])
+        for triangle in data.triangles:
+            horizontal = data.vertices[triangle, 2]
+            self.assertTrue(np.all(horizontal < 0) or np.all(horizontal > 0))
+        figure = slices.render(data, reference_outline=True, title="Analytic geometry/schema control")
+        self.assertEqual(figure.axes[0].get_aspect(), 1.)
+        self.assertEqual(figure.axes[1].get_aspect(), 1.)
+        for suffix in ("png", "pdf"):
+            path = self.directory / ("control." + suffix)
+            figure.savefig(path)
+            self.assertGreater(path.stat().st_size, 1000)
+
+    def test_cross_element_triangle_is_rejected(self):
+        write_csv(self.directory / "triangles.csv", ["triangle", "element", "v0", "v1", "v2"], [[0, 0, 0, 1, 4], [1, 1, 3, 4, 5]])
+        with self.assertRaisesRegex(ValueError, "different material elements"):
+            slices.load_slice(self.directory)
+
+    def test_wrong_physical_plane_is_rejected(self):
+        path = self.directory / "vertices.csv"
+        text = path.read_text().replace("0,0,-2,0.2,0,", "0,0,-2,0.25,0,")
+        path.write_text(text)
+        with self.assertRaisesRegex(ValueError, "physical plane"):
+            slices.load_slice(self.directory)
+
+    def test_wrong_reference_plane_is_rejected(self):
+        path = self.directory / "reference_surface.csv"
+        values = slices.table(path, ["x0", "y0", "z0", "x1", "y1", "z1", "maximum_plane_error"])
+        values[0, 1] = 0.
+        write_csv(path, ["x0", "y0", "z0", "x1", "y1", "z1", "maximum_plane_error"], values)
+        with self.assertRaisesRegex(ValueError, "outline"):
+            slices.load_slice(self.directory)
+
+    def test_shape_exaggeration_is_rejected(self):
+        path = self.directory / "metadata.csv"
+        path.write_text(path.read_text().replace("deformation_scale,1", "deformation_scale,10"))
+        with self.assertRaisesRegex(ValueError, "scale exactly one"):
+            slices.load_slice(self.directory)
+
+
+if __name__ == "__main__":
+    unittest.main()