Merge remote-tracking branch 'origin/call-method' into call-method

sawyerbfuller · sawyerbfuller · commit 94322c845872 · 2020-08-17T11:13:13.000-07:00
diff --git a/control/frdata.py b/control/frdata.py
@@ -352,10 +352,11 @@ def eval(self, omega, squeeze=True):
         entry in the omega vector. An interpolating FRD can return
         intermediate values.     
         
+        Parameters
+        ----------
         squeeze: bool, optional (default=True)
             If True and sys is single input, single output (SISO), return a 
             1D array or scalar the same length as omega.
-
         """
         omega_array = np.array(omega, ndmin=1) # array-like version of omega 
         if any(omega_array.imag > 0): 
@@ -391,12 +392,24 @@ def __call__(self, s, squeeze=True):
         transfer function.  For a MIMO transfer fuction, returns a
         matrix of values.
         
-        Raises an error if s is not purely imaginary. 
-        
+        Parameters
+        ----------
+        s : scalar or array_like
+            Complex frequencies
         squeeze: bool, optional (default=True)
             If True and sys is single input, single output (SISO), return a 
             1D array or scalar depending on omega's length.
 
+        Returns
+        -------
+        ndarray or scalar
+            Frequency response
+
+        Raises
+        ------
+        ValueError
+            If `s` is not purely imaginary. 
+
         """
         if any(abs(np.array(s, ndmin=1).real) > 0):
             raise ValueError("__call__: FRD systems can only accept"
diff --git a/control/lti.py b/control/lti.py
@@ -436,7 +436,7 @@ def evalfr(sys, x, squeeze=True):
     ----------
     sys: StateSpace or TransferFunction
         Linear system
-    x: scalar or array-like
+    x: scalar or array_like
         Complex number
     squeeze: bool, optional (default=True)
         If True and sys is single input, single output (SISO), return a 
diff --git a/control/statesp.py b/control/statesp.py
@@ -469,11 +469,14 @@ def slycot_horner(self, s):
         for a more user-friendly interface. 
 
         Parameters
-            s : array-like
+        ----------
+        s : array_like
+            Complex frequency
 
         Returns
-            output : array of size (outputs, inputs, len(s))
-        
+        -------
+        output : (outputs, inputs, len(s)) complex ndarray
+            Frequency response
         """
         from slycot import tb05ad
 
@@ -517,11 +520,14 @@ def horner(self, s):
         for a more user-friendly interface. 
 
         Parameters
-            s : array-like
+        ----------
+        s : array_like
+            Complex frequencies
 
         Returns
-            output : array of size (outputs, inputs, len(s))
-        
+        -------
+        output : (outputs, inputs, len(s)) complex ndarray
+            Frequency response
         """
         s_arr = np.array(s, ndmin=1) # force to be an array
         # Preallocate 
diff --git a/control/xferfcn.py b/control/xferfcn.py
@@ -233,11 +233,14 @@ def horner(self, s):
         for a more user-friendly interface. 
 
         Parameters
-            s : array-like
+        ----------
+        s : array_like
+            Complex frequencies
 
         Returns
-            output : array of size (outputs, inputs, len(s))
-        
+        -------
+        output : (outputs, inputs, len(s)) complex ndarray
+            Frequency response
         """
         s_arr = np.array(s, ndmin=1) # force to be an array
         out = empty((self.outputs, self.inputs, len(s_arr)), dtype=complex)
