Many small updates to make compatible with python 3.x:

murrayrm · murrayrm · commit 80b0f7b8a11c · 2012-11-03T21:03:39.000Z
* Updated unit tests to skip certain tests if slycot is not installed
 * Fixed some problems with timebase (dt) to avoid comparing None to int
 * Fixed exception syntax in a few more spots (E, T to E(T))
 * Fixed print syntax in a few more spots (backward compatible with 2.6+)
 * Updated FRD to include python 3.x fixes installed in other modules
 * tests/test_*.py scripts not working in 3.x, but individual tests OK
 * Current version works with nosetests in py2.7, py3.2 (-slycot)

Also, a few other updates not directly relate to python 3.x:

 * Added FRD to sphinx documentation
 * Set tests/{test_all.py,test_control_matlab.py} to executable so that
   they are skipped by nosetests
diff --git a/ChangeLog b/ChangeLog
@@ -1,5 +1,48 @@
 2012-11-03  Richard Murray  <murray@altura.local>
 
+	* src/rlocus.py (_RLSortRoots): convert output of range() to
+	explicit list for python 3 compatability
+
+	* tests/modelsimp_test.py, tests/slycot_convert_test.py,
+	tests/mateqn_test.py, tests/statefbk_test.py: updated test suites to
+	skip specific tests that require slycot if it is not installed
+
+	* src/exception.py (slycot_check): added a function to check if
+	slycot is installed
+
+	* README: updated readme to include information about running
+	nosetests, which works in python3 (unlike the test_all.py script)
+
+	* tests/test_control_matlab.py, tests/test_all.py: set to executable
+	so that nosetests does not run this file (it already runs all unit
+	tests in this directory).  Add comments at top talking about tests.
+
+	* tests/discrete_test.py (TestDiscrete.test_discrete_bode):
+	explicitly create a list from map() output for python 3
+
+	* src/frdata.py: removed long data type from comparisons for
+	constant systems (not supported in python3)
+
+	* src/xferfcn.py (TransferFunction.freqresp): force frequencies to
+	be a list (map returns iterator in python3)
+
+	* src/lti.py (isdtime, isctime): updated timebase checking since
+	python3 won't allow dt to be compared to integer
+
+	* src/__init__.py: updated frdata import to python3 compatible form
+
+	* src/statesp.py (_convertToStateSpace): fixed exception syntax to
+	be python3 compatible
+
+	* examples/pvtol-nested.py: converted print statements to be python3
+	compatible 
+
+	* doc/class_strings.rst: added FRD class to list of classes that
+	show up in the user documentation
+
+	* examples/rss-balred.py: fixed error in output argument order for
+	call to matlab.impulse
+
 	* ../README: updated readme file as a test of post-commit hook
 
 2012-11-02  Richard Murray  <murray@altura.local>
diff --git a/README b/README
@@ -2,9 +2,9 @@ Python Control System Library
 RMM, 23 May 09
 
 This directory contains the source code for the Python Control Systems
-Library (python-control).  This library is still under development,
-but is intended to serve as a wrapper for standard control system
-algorithms in the python programming environment.
+Library (python-control).  This library is still under development, but is
+intended to serve as a wrapper for standard control system algorithms in the
+python programming environment.
 
 Installation instructions
 -------------------------
@@ -13,13 +13,18 @@ Standard python package installation:
   python setup.py install
 
 To see if things are working, you can run the script
-examples/secord-matlab.py (using ipython -pylab).  It should generate
-a step response, Bode plot and Nyquist plot for a simple second order
-linear system.
+examples/secord-matlab.py (using ipython -pylab).  It should generate a step
+response, Bode plot and Nyquist plot for a simple second order linear
+system.
 
-You can also run a set of unit tests to make sure that everything is
-working correctly.  After installation, run
+You can also run a set of unit tests to make sure that everything is working
+correctly.  After installation, run
 
   python tests/test_all.py
 
-from the source distribution directory.
+from the source distribution directory (note: doesn't yet work in python
+3.x).  Alternatively, if you have nosetests installed, you can simply run
+
+  nosetests
+
+which gives a somewhat cleaner output (and works in python 3.x)
diff --git a/doc/class_strings.rst b/doc/class_strings.rst
@@ -10,3 +10,8 @@ Transfer Function Class
 =======================
 .. automodule:: xferfcn
    :members:
+
+FRD Class
+=========
+.. automodule:: frdata
+   :members:
diff --git a/examples/pvtol-nested.py b/examples/pvtol-nested.py
@@ -8,6 +8,7 @@
 # package.
 #
 
+from __future__ import print_function
 from matplotlib.pyplot import * # Grab MATLAB plotting functions
 from control.matlab import *    # MATLAB-like functions
 import numpy as np
@@ -142,7 +143,7 @@
 
 figure(10); clf();
 (P, Z) = pzmap(T, Plot=True)
-print "Closed loop poles and zeros: ", P, Z
+print("Closed loop poles and zeros: ", P, Z)
 
 # Gang of Four
 figure(11); clf();
diff --git a/examples/rss-balred.py b/examples/rss-balred.py
@@ -38,7 +38,7 @@
 
 # Comparison of the impulse responses of the full and reduced random systems
 plt.figure(2)
-trand, yrand = mt.impulse(sysrand)
-trandr, yrandr = mt.impulse(rsysrand)
-plt.plot(trand.T, yrand.T,trandr.T, yrandr.T) 
+yrand, trand = mt.impulse(sysrand)
+yrandr, trandr = mt.impulse(rsysrand)
+plt.plot(trand.T, yrand.T, trandr.T, yrandr.T) 
 
diff --git a/src/__init__.py b/src/__init__.py
@@ -76,7 +76,7 @@
     impulse_response
 from control.xferfcn import TransferFunction
 from control.ctrlutil import unwrap, issys
-from frdata import FRD
+from control.frdata import FRD
 
 # Import some of the more common (and benign) MATLAB shortcuts
 # By default, don't import conflicting commands here
diff --git a/src/exception.py b/src/exception.py
@@ -59,3 +59,12 @@ class ControlMIMONotImplemented(Exception):
 class ControlNotImplemented(Exception):
     """Functionality is not yet implemented"""
     pass
+
+# Utility function to see if slycot is installed
+def slycot_check():
+    try:
+        import slycot
+    except:
+        return False
+    else:
+        return True
diff --git a/src/frdata.py b/src/frdata.py
@@ -77,11 +77,10 @@
     real, imag, matrix, absolute, eye, linalg, pi, where
 from scipy.interpolate import splprep, splev
 from copy import deepcopy
-from lti import Lti
-import statesp
+from control.lti import Lti
+import control.statesp as statesp
 
 class FRD(Lti):
-
     """The FRD class represents (measured?) frequency response 
     TF instances and functions.
     
@@ -245,7 +244,7 @@ def __mul__(self, other):
         """Multiply two LTI objects (serial connection)."""
         
         # Convert the second argument to a transfer function.
-        if isinstance(other, (int, float, long, complex)):
+        if isinstance(other, (int, float, complex)):
             other = _convertToFRD(other, inputs=self.inputs, 
                 outputs=self.inputs, omega=self.omega)
         else:
@@ -287,7 +286,7 @@ def __rmul__(self, other):
     def __div__(self, other):
         """Divide two LTI objects."""
         
-        if isinstance(other, (int, float, long, complex)):
+        if isinstance(other, (int, float, complex)):
             other = _convertToFRD(other, inputs=self.inputs, 
                 outputs=self.inputs, omega=self.omega)
         else:
@@ -307,7 +306,7 @@ def __div__(self, other):
     # TODO: Division of MIMO transfer function objects is not written yet.
     def __rdiv__(self, other):
         """Right divide two LTI objects."""
-        if isinstance(other, (int, float, long, complex)):
+        if isinstance(other, (int, float, complex)):
             other = _convertToFRD(other, inputs=self.inputs, 
                 outputs=self.inputs, omega=self.omega)
         else:
@@ -443,7 +442,7 @@ def _convertToFRD(sys, omega, inputs=1, outputs=1):
         
         return FRD(fresp, omega)
 
-    elif isinstance(sys, (int, long, float, complex)):
+    elif isinstance(sys, (int, float, complex)):
         fresp = ones((outputs, inputs, len(omega)), dtype=float)*sys
         return FRD(fresp, omega)
 
diff --git a/src/lti.py b/src/lti.py
@@ -110,9 +110,12 @@ def isdtime(sys, strict=False):
 
     # Check for a transfer fucntion or state space object
     if isinstance(sys, Lti):
-        # Look for dt > 0 or dt == None (if not strict)
-        # Note that dt = True will be checked by dt > 0
-        return sys.dt > 0 or (not strict and sys.dt == None)
+        # If no timebase is given, answer depends on strict flag
+        if sys.dt == None:
+            return True if not strict else False
+
+        # Look for dt > 0 (also works if dt = True)
+        return sys.dt > 0
 
     # Got possed something we don't recognize
     return False
@@ -127,8 +130,12 @@ def isctime(sys, strict=False):
 
     # Check for a transfer fucntion or state space object
     if isinstance(sys, Lti):
-        # Look for dt == 0 or dt == None (if not strict)
-        return sys.dt == 0 or (not strict and sys.dt == None)
+        # If no timebase is given, answer depends on strict flag
+        if sys.dt == None:
+            return True if not strict else False
+
+        # Look for dt == 0
+        return sys.dt == 0
 
     # Got possed something we don't recognize
     return False
diff --git a/src/rlocus.py b/src/rlocus.py
@@ -157,7 +157,7 @@ def _RLSortRoots(sys, mymat):
             # sort the current row by finding the element with the
             # smallest absolute distance to each root in the
             # previous row
-            available = range(len(prevrow))
+            available = list(range(len(prevrow)))
             for elem in row:
                 evect = elem-prevrow[available]
                 ind1 = abs(evect).argmin()
diff --git a/src/statesp.py b/src/statesp.py
@@ -83,7 +83,7 @@
 from numpy.linalg import inv, det, solve
 from numpy.linalg.linalg import LinAlgError
 from scipy.signal import lti
-from exceptions import Exception
+# from exceptions import Exception
 import warnings
 from control.lti import Lti, timebaseEqual, isdtime
 
@@ -577,7 +577,7 @@ def _convertToStateSpace(sys, **kw):
         outputs, inputs = D.shape
         
         return StateSpace(0., zeros((1, inputs)), zeros((outputs, 1)), D)
-    except Exception, e: 
+    except Exception(e): 
         print("Failure to assume argument is matrix-like in" \
             " _convertToStateSpace, result %s" % e)
         
diff --git a/src/xferfcn.py b/src/xferfcn.py
@@ -293,7 +293,7 @@ def __str__(self, var=None):
                 outstr += "\n" + numstr + "\n" + dashes + "\n" + denstr + "\n"
 
         # See if this is a discrete time system with specific sampling time
-        if (type(self.dt) != bool and self.dt > 0):
+        if (not (self.dt is None) and type(self.dt) != bool and self.dt > 0):
             outstr += "\ndt = " + self.dt.__str__() + "\n"
 
         return outstr
@@ -527,7 +527,7 @@ def freqresp(self, omega):
             for j in range(self.inputs):
                 fresp = map(lambda s: (polyval(self.num[i][j], s) / 
                     polyval(self.den[i][j], s)), slist)
-                fresp = array(fresp)
+                fresp = array(list(fresp))
 
                 mag[i, j, :] = abs(fresp)
                 phase[i, j, :] = angle(fresp)
diff --git a/tests/discrete_test.py b/tests/discrete_test.py
@@ -276,7 +276,7 @@ def test_discrete_bode(self):
         sys = TransferFunction([1], [1, 0.5], 1)
         omega = [1, 2, 3]
         mag_out, phase_out, omega_out = bode(sys, omega)
-        H_z = map(lambda w: 1./(np.exp(1.j * w) + 0.5), omega)
+        H_z = list(map(lambda w: 1./(np.exp(1.j * w) + 0.5), omega))
         np.testing.assert_array_almost_equal(omega, omega_out)
         np.testing.assert_array_almost_equal(mag_out, np.absolute(H_z))
         np.testing.assert_array_almost_equal(mag_out, np.absolute(H_z))
diff --git a/tests/mateqn_test.py b/tests/mateqn_test.py
@@ -47,17 +47,12 @@
 from numpy.linalg import inv
 from scipy import zeros,dot
 from control.mateqn import lyap,dlyap,care,dare
+from control.exception import slycot_check
 
-# Test cases (lyap and dlyap)
-
+@unittest.skipIf(not slycot_check(), "slycot not installed")
 class TestMatrixEquations(unittest.TestCase):
     """These are tests for the matrix equation solvers in mateqn.py"""
 
-    def setUp(self):
-        # Make sure that the slycot functions that we require exist
-        from slycot import sb02md, sb02mt, sb03md, sb04md, sg02ad, \
-            sg03ad, sb04qd
-
     def test_lyap(self):
         A = array([[-1, 1],[-1, 0]])
         Q = array([[1,0],[0,1]])
diff --git a/tests/modelsimp_test.py b/tests/modelsimp_test.py
@@ -7,8 +7,10 @@
 import numpy as np
 from control.modelsimp import *
 from control.matlab import *
+from control.exception import slycot_check
 
 class TestModelsimp(unittest.TestCase):
+    @unittest.skipIf(not slycot_check(), "slycot not installed")
     def testHSVD(self):
         A = np.matrix("1. -2.; 3. -4.")
         B = np.matrix("5.; 7.")
@@ -69,6 +71,8 @@ def testModredTruncate(self):
         np.testing.assert_array_almost_equal(rsys.C, Crtrue)
         np.testing.assert_array_almost_equal(rsys.D, Drtrue)
 
+
+    @unittest.skipIf(not slycot_check(), "slycot not installed")
     def testBalredTruncate(self):
         #controlable canonical realization computed in matlab for the transfer function:
         # num = [1 11 45 32], den = [1 15 60 200 60]
diff --git a/tests/rlocus_test.py b/tests/rlocus_test.py
@@ -23,7 +23,7 @@ def setUp(self):
 
     def testRootLocus(self):
         """Basic root locus plot"""
-        klist = [-1, 0, 1];
+        klist = [-1, 0, 1]
         rlist = root_locus(self.sys1, [-1, 0, 1], Plot=False)
 
         for k in klist:
diff --git a/tests/slycot_convert_test.py b/tests/slycot_convert_test.py
@@ -7,7 +7,9 @@
 import unittest
 import numpy as np
 import control.matlab as matlab
+from control.exception import slycot_check
 
+@unittest.skipIf(not slycot_check(), "slycot not installed")
 class TestSlycot(unittest.TestCase):
     """TestSlycot compares transfer function and state space conversions for
         various numbers of inputs,outputs and states. 
diff --git a/tests/statefbk_test.py b/tests/statefbk_test.py
@@ -8,6 +8,7 @@
 import numpy as np
 from control.statefbk import ctrb, obsv, place, lqr, gram, acker
 from control.matlab import *
+from control.exception import slycot_check
 
 class TestStatefbk(unittest.TestCase):
     """Test state feedback functions"""
@@ -57,6 +58,7 @@ def testCtrbObsvDuality(self):
         Wo = np.transpose(obsv(A,C));
         np.testing.assert_array_almost_equal(Wc,Wo)
 
+    @unittest.skipIf(not slycot_check(), "slycot not installed")
     def testGramWc(self):
         A = np.matrix("1. -2.; 3. -4.")
         B = np.matrix("5. 6.; 7. 8.")
@@ -67,6 +69,7 @@ def testGramWc(self):
         Wc = gram(sys,'c')
         np.testing.assert_array_almost_equal(Wc, Wctrue)
 
+    @unittest.skipIf(not slycot_check(), "slycot not installed")
     def testGramWo(self):
         A = np.matrix("1. -2.; 3. -4.")
         B = np.matrix("5. 6.; 7. 8.")
@@ -77,6 +80,7 @@ def testGramWo(self):
         Wo = gram(sys,'o')
         np.testing.assert_array_almost_equal(Wo, Wotrue)
 
+    @unittest.skipIf(not slycot_check(), "slycot not installed")
     def testGramWo2(self):
         A = np.matrix("1. -2.; 3. -4.")
         B = np.matrix("5.; 7.")
diff --git a/tests/statesp_test.py b/tests/statesp_test.py
@@ -5,7 +5,7 @@
 
 import unittest
 import numpy as np
-import control.matlab
+import control.matlab as matlab
 from control.statesp import StateSpace
 
 class TestStateSpace(unittest.TestCase):
diff --git a/tests/test_all.py b/tests/test_all.py
diff --git a/tests/test_control_matlab.py b/tests/test_control_matlab.py
