Added return_x to step_response

KronosKoderS · KronosKoderS · commit a660fbd55149 · 2016-05-04T21:43:34.000-07:00
Added the ability to return the individual x variable responses from the
step_response function.  Also updated matlab version to match matlab
returns.
diff --git a/control/matlab/timeresp.py b/control/matlab/timeresp.py
@@ -6,7 +6,7 @@
 
 __all__ = ['step', 'impulse', 'initial', 'lsim']
 
-def step(sys, T=None, X0=0., input=0, output=None):
+def step(sys, T=None, X0=0., input=0, output=None, return_x=False):
     '''
     Step response of a linear system
 
@@ -40,9 +40,14 @@ def step(sys, T=None, X0=0., input=0, output=None):
     yout: array
         Response of the system
 
+    xout: array (if selected)
+        Individual response of each x variable
+
     T: array
         Time values of the output
 
+
+
     See Also
     --------
     lsim, initial, impulse
@@ -52,8 +57,14 @@ def step(sys, T=None, X0=0., input=0, output=None):
     >>> yout, T = step(sys, T, X0)
     '''
     from ..timeresp import step_response
-    T, yout = step_response(sys, T, X0, input, output,
-                            transpose = True)
+
+
+    T, yout, xout = step_response(sys, T, X0, input, output,
+                            transpose = True, return_x=return_x)
+
+    if return_x:
+        return yout, xout, T
+
     return yout, T
 
 def impulse(sys, T=None, input=0, output=None):
diff --git a/control/timeresp.py b/control/timeresp.py
@@ -417,7 +417,7 @@ def _get_ss_simo(sys, input=None, output=None):
         return _mimo2siso(sys_ss, input, output, warn_conversion=warn)
 
 def step_response(sys, T=None, X0=0., input=None, output=None,
-                  transpose=False):
+                  transpose=False, return_x=False):
     # pylint: disable=W0622
     """Step response of a linear system
 
@@ -461,6 +461,9 @@ def step_response(sys, T=None, X0=0., input=None, output=None,
     yout: array
         Response of the system
 
+    xout: array
+        Individual response of each x variable
+
     See Also
     --------
     forced_response, initial_response, impulse_response
@@ -480,9 +483,12 @@ def step_response(sys, T=None, X0=0., input=None, output=None,
 
     U = np.ones_like(T)
 
-    T, yout, _xout = forced_response(sys, T, U, X0,
+    T, yout, xout = forced_response(sys, T, U, X0,
                                      transpose=transpose)
 
+    if return_x:
+        return T, yout, xout
+
     return T, yout
 
 
