python-control
diff --git a/‎control/tests/statefbk_matrix_test.py‎
Lines changed: 0 additions & 365 deletions b/‎control/tests/statefbk_matrix_test.py‎
Lines changed: 0 additions & 365 deletions
diff --git a/‎control/tests/statefbk_test.py‎
Lines changed: 15 additions & 1 deletion b/‎control/tests/statefbk_test.py‎
Lines changed: 15 additions & 1 deletion
@@ -8,7 +8,7 @@
 import numpy as np
 import pytest
 
-from control import pole, rss, ss, tf
+from control import lqe, pole, rss, ss, tf
 from control.exception import ControlDimension
 from control.mateqn import care, dare
 from control.statefbk import ctrb, obsv, place, place_varga, lqr, gram, acker
@@ -324,6 +324,20 @@ def test_LQR_3args(self):
         K, S, poles = lqr(sys, Q, R)
         self.check_LQR(K, S, poles, Q, R)
 
+    def check_LQE(self, L, P, poles, G, QN, RN):
+        P_expected = np.array(np.sqrt(G*QN*G * RN))
+        L_expected = P_expected / RN
+        poles_expected = np.array([-L_expected], ndmin=2)
+        np.testing.assert_array_almost_equal(P, P_expected)
+        np.testing.assert_array_almost_equal(L, L_expected)
+        np.testing.assert_array_almost_equal(poles, poles_expected)
+
+    @slycotonly
+    def test_LQE(self):
+        A, G, C, QN, RN = 0., .1, 1., 10., 2.
+        L, P, poles = lqe(A, G, C, QN, RN)
+        self.check_LQE(L, P, poles, G, QN, RN)
+
     @slycotonly
     def test_care(self):
         #unit test for stabilizing and anti-stabilizing feedbacks