Add rot_3D and tests for rot_2D/rot_3D

diff.py

@@ -1,2 +0,0 @@
-print("APOLLO")
-print("hallo")

pyproject.toml

@@ -2,4 +2,13 @@
 name = "matrixmania"
 version = "0.1.0"
 
-dependencies = ["tabulate", "ruff"]
+dependencies = ["tabulate", "ruff"]
+
+[project.optional-dependencies]
+dev = ["pytest", "ruff", "pytest-cov"]
+
+[tool.pytest.ini_options]
+pythonpath = "src"
+testpaths = "test"
+
+

src/matrixmania/compute.py

@@ -1,5 +1,5 @@
 import math
-from tabulate import tabulate
+
 
 def matmul(matrix_a: list[list[float | int]], matrix_b: list[list[float | int]]) -> list[list[float | int]]:
     """Multipliziert zwei Matrizen, die als verschachtelte Listen dargestellt sind.
@@ -91,6 +91,37 @@ def rot_2D(theta: float) -> list[list[float]]:
         [sin_theta, cos_theta]
     ]
 
+def rot_3D(angle: float, axis: str) -> list[list[float]]:
+    """Gibt die 3D-Rotationsmatrix um eine Koordinatenachse zurück.
+
+    Formeln (θ = angle, im Bogenmaß):
+        R_x(θ) = [[1, 0, 0], [0, cos θ, -sin θ], [0, sin θ, cos θ]]
+        R_y(θ) = [[cos θ, 0, sin θ], [0, 1, 0], [-sin θ, 0, cos θ]]
+        R_z(θ) = [[cos θ, -sin θ, 0], [sin θ, cos θ, 0], [0, 0, 1]]
+
+    Args:
+        angle: Der Rotationswinkel in Bogenmaß (Radians).
+        axis: Die Rotationsachse: "x", "y" oder "z".
+
+    Returns:
+        Die 3x3-Rotationsmatrix als 2D-Liste.
+
+    Raises:
+        ValueError: Wenn axis nicht "x", "y" oder "z" ist.
+    """
+    c = math.cos(angle)
+    s = math.sin(angle)
+
+    if axis == "x":
+        return [[1.0, 0.0, 0.0], [0.0, c, -s], [0.0, s, c]]
+    if axis == "y":
+        return [[c, 0.0, s], [0.0, 1.0, 0.0], [-s, 0.0, c]]
+    if axis == "z":
+        return [[c, -s, 0.0], [s, c, 0.0], [0.0, 0.0, 1.0]]
+
+    raise ValueError(f"Ungültige Achse '{axis}': erlaubt sind 'x', 'y' oder 'z'.")
+
+
 
 if __name__ == "__main__":
 
@@ -154,8 +185,7 @@ if __name__ == "__main__":
     theta = math.pi / 2 #1,57...
     print(f"Winkel: {math.degrees(theta)} Grad (pi / 2)")
     print(rot_2D(theta))
-    print(tabulate(rot_2D(1.0)))
+    print(rot_2D(1.0))
+
 
-print("hallo")
-print("apollo")
 

test/test_matrixmania/test_rot.py

@@ -0,0 +1,58 @@
+import math
+
+import pytest
+
+from matrixmania.compute import matmul, rot_2D, rot_3D, transpose
+
+
+def assert_matrix_close(actual, expected):
+    """Vergleicht zwei Matrizen elementweise mit Toleranz."""
+    assert len(actual) == len(expected)
+    for row_a, row_e in zip(actual, expected):
+        assert row_a == pytest.approx(row_e, abs=1e-9)
+
+
+# ---------- rot_2D ----------
+
+def test_rot_2D_zero():
+    assert_matrix_close(rot_2D(0), [[1, 0], [0, 1]])
+
+
+def test_rot_2D_90_degree():
+    assert_matrix_close(rot_2D(math.pi / 2), [[0, -1], [1, 0]])
+
+
+def test_rot_2D_invalid_input():
+    with pytest.raises(TypeError):
+        rot_2D("abc")
+
+
+# ---------- rot_3D ----------
+
+@pytest.mark.parametrize("axis", ["x", "y", "z"])
+def test_rot_3D_zero_is_identity(axis):
+    assert_matrix_close(rot_3D(0, axis), [[1, 0, 0], [0, 1, 0], [0, 0, 1]])
+
+
+@pytest.mark.parametrize(
+    "axis, expected",
+    [
+        ("x", [[1, 0, 0], [0, 0, -1], [0, 1, 0]]),
+        ("y", [[0, 0, 1], [0, 1, 0], [-1, 0, 0]]),
+        ("z", [[0, -1, 0], [1, 0, 0], [0, 0, 1]]),
+    ],
+)
+def test_rot_3D_90_degree(axis, expected):
+    assert_matrix_close(rot_3D(math.pi / 2, axis), expected)
+
+
+@pytest.mark.parametrize("axis", ["x", "y", "z"])
+def test_rot_3D_is_orthogonal(axis):
+    r = rot_3D(1.0, axis)
+    assert_matrix_close(matmul(r, transpose(r)), [[1, 0, 0], [0, 1, 0], [0, 0, 1]])
+
+
+@pytest.mark.parametrize("axis", ["w", "X", "", "xy"])
+def test_rot_3D_invalid_axis(axis):
+    with pytest.raises(ValueError):
+        rot_3D(1.0, axis)