Added a test case for the reachable canon. form

mp4096 · mp4096 · commit af36e84759d1 · 2016-11-20T21:08:11.000+01:00
diff --git a/control/tests/canonical_test.py b/control/tests/canonical_test.py
@@ -0,0 +1,41 @@
+#!/usr/bin/env python
+
+import unittest
+import numpy as np
+from control import ss
+from control.canonical import canonical_form
+
+
+class TestCanonical(unittest.TestCase):
+    """Tests for the canonical forms class"""
+
+    def test_reachable_form(self):
+        """Test the reachable canonical form"""
+
+        # Create a system in the reachable canonical form
+        coeffs = [1.0, 2.0, 3.0, 4.0, 1.0]
+        A_true = np.polynomial.polynomial.polycompanion(coeffs)
+        A_true = np.fliplr(np.rot90(A_true))
+        B_true = np.matrix("1.0 0.0 0.0 0.0").T
+        C_true = np.matrix("1.0 1.0 1.0 1.0")
+        D_true = 42.0
+
+        # Perform a coordinate transform with a random invertible matrix
+        T_true = np.matrix([[-0.27144004, -0.39933167,  0.75634684,  0.44135471],
+                            [-0.74855725, -0.39136285, -0.18142339, -0.50356997],
+                            [-0.40688007,  0.81416369,  0.38002113, -0.16483334],
+                            [-0.44769516,  0.15654653, -0.50060858,  0.72419146]])
+        A = np.linalg.solve(T_true, A_true)*T_true
+        B = np.linalg.solve(T_true, B_true)
+        C = C_true*T_true
+        D = D_true
+
+        # Create a state space system and convert it to the reachable canonical form
+        sys_check, T_check = canonical_form(ss(A, B, C, D), "reachable")
+
+        # Check against the true values
+        np.testing.assert_array_almost_equal(sys_check.A, A_true)
+        np.testing.assert_array_almost_equal(sys_check.B, B_true)
+        np.testing.assert_array_almost_equal(sys_check.C, C_true)
+        np.testing.assert_array_almost_equal(sys_check.D, D_true)
+        np.testing.assert_array_almost_equal(T_check, T_true)
