added field to interconnectedSystem and LinearICSystem to keep track …

…of whether connection was explicit or implicit and issue a warning in connection_table if explicit
murrayrm · Sep 16, 2023 · Jul 21, 2023 · Jul 24, 2023 · Jul 24, 2023 · Jul 24, 2023
commit 58e1b601e84c2943a5a62eb42767a50da4627498
diff --git a/control/nlsys.py b/control/nlsys.py
@@ -589,11 +589,14 @@ class InterconnectedSystem(NonlinearIOSystem):
 
     """
     def __init__(self, syslist, connections=None, inplist=None, outlist=None,
-                 params=None, warn_duplicate=None, **kwargs):
+                 params=None, warn_duplicate=None, connection_type=None,
+                 **kwargs):
         """Create an I/O system from a list of systems + connection info."""
         from .statesp import _convert_to_statespace
         from .xferfcn import TransferFunction
 
+        self.connection_type = connection_type # explicit, implicit, or None
+
         # Convert input and output names to lists if they aren't already
         if inplist is not None and not isinstance(inplist, list):
             inplist = [inplist]
@@ -1034,8 +1037,10 @@ def connection_table(self, show_names=False, column_width=32):
             '| destination')
         print('-'*(10 + column_width * 2))
 
-        # TODO: version of this method that is better suited
-        # to explicitly-connected systems
+        # TODO: update this method for explicitly-connected systems
+        if not self.connection_type == 'implicit':
+            warn('connection_table only gives useful output for implicitly-'\
+                'connected systems')
 
         # collect signal labels
         signal_labels = []
@@ -2239,6 +2244,7 @@ def interconnect(
 
     dt = kwargs.pop('dt', None)         # bypass normal 'dt' processing
     name, inputs, outputs, states, _ = _process_iosys_keywords(kwargs)
+    connection_type = None # explicit, implicit, or None
 
     if not check_unused and (ignore_inputs or ignore_outputs):
         raise ValueError('check_unused is False, but either '
@@ -2249,8 +2255,10 @@ def interconnect(
         # nor output mappings; assume they know what they're doing
         check_unused = False
 
-    # If connections was not specified, set up default connection list
+    # If connections was not specified, assume implicit interconnection.
+    # set up default connection list
     if connections is None:
+        connection_type = 'implicit'
         # For each system input, look for outputs with the same name
         connections = []
         for input_sys in syslist:
@@ -2262,17 +2270,17 @@ def interconnect(
                 if len(connect) > 1:
                     connections.append(connect)
 
-        auto_connect = True
-
     elif connections is False:
         check_unused = False
         # Use an empty connections list
         connections = []
 
-    elif isinstance(connections, list) and \
-         all([isinstance(cnxn, (str, tuple)) for cnxn in connections]):
-        # Special case where there is a single connection
-        connections = [connections]
+    else:
+        connection_type = 'explicit'
+        if isinstance(connections, list) and \
+                all([isinstance(cnxn, (str, tuple)) for cnxn in connections]):
+            # Special case where there is a single connection
+            connections = [connections]
 
     # If inplist/outlist is not present, try using inputs/outputs instead
     inplist_none, outlist_none = False, False
@@ -2507,7 +2515,7 @@ def interconnect(
         syslist, connections=connections, inplist=inplist,
         outlist=outlist, inputs=inputs, outputs=outputs, states=states,
         params=params, dt=dt, name=name, warn_duplicate=warn_duplicate,
-        **kwargs)
+        connection_type=connection_type, **kwargs)
 
     # See if we should add any signals
     if add_unused:
@@ -2528,15 +2536,15 @@ def interconnect(
             syslist, connections=connections, inplist=inplist,
             outlist=outlist, inputs=inputs, outputs=outputs, states=states,
             params=params, dt=dt, name=name, warn_duplicate=warn_duplicate,
-            **kwargs)
+            connection_type=connection_type, **kwargs)
 
     # check for implicitly dropped signals
     if check_unused:
         newsys.check_unused_signals(ignore_inputs, ignore_outputs)
 
     # If all subsystems are linear systems, maintain linear structure
     if all([isinstance(sys, StateSpace) for sys in newsys.syslist]):
-        return LinearICSystem(newsys, None)
+        newsys = LinearICSystem(newsys, None, connection_type=connection_type)
 
     return newsys
 
@@ -2606,4 +2614,4 @@ def connection_table(sys, show_names=False, column_width=32):
     assert isinstance(sys, InterconnectedSystem), "system must be"\
         "an InterconnectedSystem."
 
-    sys.connection_table(show_names=show_names)
+    sys.connection_table(show_names=show_names, column_width=column_width)
diff --git a/control/statesp.py b/control/statesp.py
@@ -1459,7 +1459,7 @@ class LinearICSystem(InterconnectedSystem, StateSpace):
 
     """
 
-    def __init__(self, io_sys, ss_sys=None):
+    def __init__(self, io_sys, ss_sys=None, connection_type=None):
         #
         # Because this is a "hybrid" object, the initialization proceeds in
         # stages.  We first create an empty InputOutputSystem of the
@@ -1483,6 +1483,7 @@ def __init__(self, io_sys, ss_sys=None):
         self.input_map = io_sys.input_map
         self.output_map = io_sys.output_map
         self.params = io_sys.params
+        self.connection_type = connection_type
 
         # If we didnt' get a state space system, linearize the full system
         if ss_sys is None:

diff --git a/control/tests/interconnect_test.py b/control/tests/interconnect_test.py
@@ -276,7 +276,7 @@ def test_connection_table(capsys, show_names):
 
     mystrings = \
             ["signal    | source                        | destination",
-     "-------------------------------------------------------------------"]
+             "-------------------------------------------------------------------"]
     if show_names:
         mystrings += \
             ["u         | input                         | P1, P2, P3",
@@ -294,6 +294,34 @@ def test_connection_table(capsys, show_names):
         assert str_ in captured_from_method
         assert str_ in captured_from_function
 
+    # check change column width
+    P.connection_table(show_names=show_names, column_width=20)
+    captured_from_method = capsys.readouterr().out
+
+    ct.connection_table(P, show_names=show_names, column_width=20)
+    captured_from_function = capsys.readouterr().out
+
+    mystrings = \
+            ["signal    | source            | destination",
+             "------------------------------------------------"]
+    if show_names:
+        mystrings += \
+            ["u         | input             | P1, P2, P3",
+             "x         | P1                | output  ",
+             "y         | P2                | output",
+             "z         | P3                | output"]
+    else:
+        mystrings += \
+            ["u         | input             | system 0, syste.. ",
+             "x         | system 0          | output  ",
+             "y         | system 1          | output",
+             "z         | system 2          | output"]
+
+    for str_ in mystrings:
+        assert str_ in captured_from_method
+        assert str_ in captured_from_function
+
+
 def test_interconnect_exceptions():
     # First make sure the docstring example works
     P = ct.tf(1, [1, 0], input='u', output='y')