Addressing PR comments

Andrew D. McGuire · Andrew D. McGuire · commit 8b084810ae1a · 2019-08-09T09:51:51.000-04:00
diff --git a/control/tests/timeresp_test.py b/control/tests/timeresp_test.py
@@ -252,7 +252,7 @@ def test_forced_response(self):
         # first system: initial value, second system: step response
         u = np.array([[0., 0, 0, 0, 0, 0, 0, 0, 0, 0],
                       [1., 1, 1, 1, 1, 1, 1, 1, 1, 1]])
-        x0 = np.matrix(".5; 1; 0; 0")
+        x0 = np.array([[.5], [1], [0], [0]])
         youttrue = np.array([[11., 8.1494, 5.9361, 4.2258, 2.9118, 1.9092,
                               1.1508, 0.5833, 0.1645, -0.1391],
                              [9., 17.6457, 24.7072, 30.4855, 35.2234, 39.1165,
@@ -273,7 +273,7 @@ def test_forced_response(self):
         # Test discrete MIMO system without default T argument
         u = np.array([[0., 0, 0, 0, 0, 0, 0, 0, 0, 0],
                       [1., 1, 1, 1, 1, 1, 1, 1, 1, 1]])
-        x0 = np.matrix(".5; 1; 0; 0")
+        x0 = np.array([[.5], [1], [0], [0]])
         youttrue = np.array([[11., 8.1494, 5.9361, 4.2258, 2.9118, 1.9092,
                               1.1508, 0.5833, 0.1645, -0.1391],
                              [9., 17.6457, 24.7072, 30.4855, 35.2234, 39.1165,
diff --git a/control/timeresp.py b/control/timeresp.py
@@ -273,14 +273,16 @@ def forced_response(sys, T=None, U=0., X0=0., transpose=False,
                 raise ValueError('Parameters ``T`` and ``U`` can\'t both be'
                                  'zero for discrete-time simulation')
             # Set T to equally spaced samples with same length as U
-            if len(U.shape) == 1:
+            if U.ndim == 1:
                 n_steps = U.shape[0]
             else:
                 n_steps = U.shape[1]
             T = np.array(range(n_steps)) * (1 if sys.dt is True else sys.dt)
         else:
             # Make sure the input vector and time vector have same length
-            if (len(U.shape) == 1 and U.shape[0] != T.shape[0]) or (len(U.shape) > 1 and U.shape[1] != T.shape[0]):
+            # TODO: allow interpolation of the input vector
+            if (U.ndim == 1 and U.shape[0] != T.shape[0]) or \
+                    (U.ndim > 1 and U.shape[1] != T.shape[0]):
                 ValueError('Pamameter ``T`` must have same elements as'
                            ' the number of columns in input array ``U``')
 
