added unit test for riccati equation

Daniel Bankmann · Daniel Bankmann · commit 3ece9aa539e7 · 2019-03-21T18:51:21.000+01:00
diff --git a/examples/test-riccati.py b/examples/test-riccati.py
@@ -0,0 +1,30 @@
+import numpy as np
+import control
+
+
+#unit test for stabilizing and anti-stabilizing feedbacks
+#continuous-time
+
+A = np.diag([1,-1])
+B = np.identity(2)
+Q = np.identity(2)
+R = np.identity(2)
+S = 0 * B
+E = np.identity(2)
+X, L , G = control.care(A, B, Q, R, S, E, stabilizing=True)
+assert np.all(np.real(L) < 0)
+X, L , G = control.care(A, B, Q, R, S, E, stabilizing=False)
+assert np.all(np.real(L) > 0)
+
+
+#discrete-time
+A = np.diag([0.5,2])
+B = np.identity(2)
+Q = np.identity(2)
+R = np.identity(2)
+S = 0 * B
+E = np.identity(2)
+X, L , G = control.dare(A, B, Q, R, S, E, stabilizing=True)
+assert np.all(np.abs(L) < 1)
+X, L , G = control.dare(A, B, Q, R, S, E, stabilizing=False)
+assert np.all(np.abs(L) > 1)
