Bug fixes in convertToStateSpace; new TestConvert.py

Kevin Chen · Kevin Chen · commit e3b087f285a6 · 2011-02-08T22:17:03.000Z
Kevin K. Chen &lt;kkchen@princeton.edu&gt;
diff --git a/src/TestConvert.py b/src/TestConvert.py
@@ -0,0 +1,36 @@
+#!/usr/bin/env python
+
+import numpy as np
+import matlab
+import unittest
+
+class TestConvert(unittest.TestCase):
+    """Test state space and transfer function conversions."""
+
+    def setUp(self):
+        """Set up testing parameters."""
+
+        # Number of times to run each of the randomized tests.
+        self.numTests = 10
+        # Maximum number of states to test + 1
+        self.maxStates = 5
+        # Maximum number of inputs and outputs to test + 1
+        self.maxIO = 5
+
+    def testConvert(self):
+        """Test state space to transfer function conversion."""
+
+        for states in range(1, self.maxStates):
+            for inputs in range(1, self.maxIO):
+                for outputs in range(1, self.maxIO):
+                    sys = matlab.rss(states, inputs, outputs)
+                    print "sys1:\n", sys
+                    sys2 = matlab.tf(sys)
+                    print "sys2:\n", sys2
+                    sys3 = matlab.ss(sys2)
+                    print "sys3:\n", sys3
+                    sys4 = matlab.tf(sys3)
+                    print "sys4:\n", sys4
+
+if __name__ == "__main__":
+    unittest.main()
diff --git a/src/TestStateSp.py b/src/TestStateSp.py
@@ -1,9 +1,9 @@
 #!/usr/bin/env python
 
 import numpy as np
+import unittest
 import matlab
 from statesp import StateSpace
-import unittest
 
 class TestStateSpace(unittest.TestCase):
     """Tests for the StateSpace class."""
diff --git a/src/statesp.py b/src/statesp.py
@@ -433,13 +433,18 @@ def convertToStateSpace(sys, **kw):
         # function matrix has a common denominator.
         num, den = sys._common_den()
         # Make a list of the orders of the denominator polynomials.
-        index = [len(den) for i in range(sys.outputs)]
+        index = [len(den) - 1 for i in range(sys.outputs)]
         # Repeat the common denominator along the rows.
         den = array([den for i in range(sys.outputs)])
 
+        print "outputs = %g\n" % sys.outputs
         ssout = td04ad(sys.inputs, sys.outputs, index, den, num)
 
-        return StateSpace(ssout[1], ssout[2], ssout[3], ssout[4])
+        states = ssout[0]
+        return StateSpace(ssout[1][:states, :states],
+            ssout[2][:states, :sys.inputs], 
+            ssout[3][:sys.outputs, :states], 
+            ssout[4])
     elif isinstance(sys, (int, long, float, complex)):
         if "inputs" in kw:
             inputs = kw["inputs"]
