Merge pull request #588 from bnavigator/timeresp-doc

improve forced_response and its documentation
python-control · Apr 2, 2021 · 5434318 · 5434318
2 parents de87cc6 + a8b72f5
commit 5434318
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Showing 4 changed files with 416 additions and 381 deletions.
diff --git a/control/tests/modelsimp_test.py b/control/tests/modelsimp_test.py
@@ -65,8 +65,6 @@ def testMarkovSignature(self, matarrayout, matarrayin):
             markov(Y, U, m)
 
     # Make sure markov() returns the right answer
-    # forced response can return wrong shape until gh-488 is merged
-    @pytest.mark.xfail
     @pytest.mark.parametrize("k, m, n",
                              [(2, 2, 2),
                               (2, 5, 5),
@@ -81,7 +79,7 @@ def testMarkovResults(self, k, m, n):
         # m = number of Markov parameters
         # n = size of the data vector
         #
-        # Values should match exactly for n = m, otherewise you get a
+        # Values *should* match exactly for n = m, otherewise you get a
         # close match but errors due to the assumption that C A^k B =
         # 0 for k > m-2 (see modelsimp.py).
         #
@@ -108,7 +106,10 @@ def testMarkovResults(self, k, m, n):
         Mcomp = markov(Y, U, m)
 
         # Compare to results from markov()
-        np.testing.assert_array_almost_equal(Mtrue, Mcomp)
+        # experimentally determined probability to get non matching results
+        # with rtot=1e-6 and atol=1e-8 due to numerical errors
+        # for k=5, m=n=10: 0.015 %
+        np.testing.assert_allclose(Mtrue, Mcomp, rtol=1e-6, atol=1e-8)
 
     def testModredMatchDC(self, matarrayin):
         #balanced realization computed in matlab for the transfer function:
@@ -219,4 +220,3 @@ def testBalredMatchDC(self, matarrayin):
         np.testing.assert_array_almost_equal(rsys.B, Brtrue, decimal=4)
         np.testing.assert_array_almost_equal(rsys.C, Crtrue, decimal=4)
         np.testing.assert_array_almost_equal(rsys.D, Drtrue, decimal=4)
-