missed a couple of doc updates in xferfcn

sawyerbfuller · bnavigator · web-flow · commit a63109883743 · 2021-01-07T11:57:47.000-08:00
Co-authored-by: Ben Greiner &lt;code@bnavigator.de&gt;
diff --git a/control/xferfcn.py b/control/xferfcn.py
@@ -237,22 +237,26 @@ def __call__(self, x, squeeze=True):
         Returns the complex frequency response `sys(x)` where `x` is `s` for
         continuous-time systems and `z` for discrete-time systems.
 
+        In general the system may be multiple input, multiple output (MIMO), where
+        `m = self.inputs` number of inputs and `p = self.outputs` number of
+        outputs.
+        
         To evaluate at a frequency omega in radians per second, enter
         ``x = omega * 1j``, for continuous-time systems, or
         ``x = exp(1j * omega * dt)`` for discrete-time systems. Or use
         :meth:`TransferFunction.frequency_response`.
 
         Parameters
         ----------
-        x: complex array_like or complex
+        x : complex array_like or complex
             Complex frequencies
-        squeeze: bool, optional (default=True)
+        squeeze : bool, optional (default=True)
             If True and `sys` is single input single output (SISO), returns a
-            1D array or scalar depending on the length of `x`.
+            1D array rather than a 3D array.
 
         Returns
         -------
-        fresp : (self.outputs, self.inputs, len(x)) or len(x) complex ndarray
+        fresp : (p, m, len(x)) complex ndarray or or (len(x), ) complex ndarray
             The frequency response of the system. Array is `len(x)` if and
             only if system is SISO and ``squeeze=True``.
 
