expanded __str__ for IC systems (subsys list + connection map)

Author: murrayrm

control/nlsys.py

@@ -26,7 +26,7 @@
 
 from . import config
 from .iosys import InputOutputSystem, _parse_spec, _process_iosys_keywords, \
-    _process_signal_list, common_timebase, isctime, isdtime
+    _process_signal_list, common_timebase, iosys_repr, isctime, isdtime
 from .timeresp import _check_convert_array, _process_time_response, \
     TimeResponseData, TimeResponseList
 
@@ -773,6 +773,71 @@ def outfcn(t, x, u, params):
                              index + "; combining with previous entries")
                     self.output_map[index + j, ylist_index] += gain
 
+    def __str__(self):
+        import textwrap
+        out = super().__str__()
+
+        out += f"\n\nSubsystems ({len(self.syslist)}):\n"
+        for sys in self.syslist:
+            out += "\n".join(textwrap.wrap(
+                iosys_repr(sys, format='info'), width=78,
+                initial_indent=" * ", subsequent_indent="    ")) + "\n"
+
+        # Build a list of input, output, and inpout signals
+        input_list, output_list, inpout_list = [], [], []
+        for sys in self.syslist:
+            input_list += [sys.name + "." + lbl for lbl in sys.input_labels]
+            output_list += [sys.name + "." + lbl for lbl in sys.output_labels]
+        inpout_list = input_list + output_list
+
+        # Define a utility function to generate the signal
+        def cxn_string(signal, gain, first):
+            if gain == 1:
+                return (" + " if not first else "") + f"{signal}"
+            elif gain == -1:
+                return (" - " if not first else "-") + f"{signal}"
+            elif gain > 0:
+                return (" + " if not first else "") + f"{gain} * {signal}"
+            elif gain < 0:
+                return (" - " if not first else "-") + \
+                    f"{abs(gain)} * {signal}"
+
+        out += f"\nConnections:\n"
+        for i in range(len(input_list)):
+            first = True
+            cxn = f"{input_list[i]} <- "
+            if np.any(self.connect_map[i]):
+                for j in range(len(output_list)):
+                    if self.connect_map[i, j]:
+                        cxn += cxn_string(
+                            output_list[j], self.connect_map[i,j], first)
+                        first = False
+            if np.any(self.input_map[i]):
+                for j in range(len(self.input_labels)):
+                    if self.input_map[i, j]:
+                        cxn += cxn_string(
+                            self.input_labels[j], self.input_map[i, j], first)
+                        first = False
+            out += "\n".join(textwrap.wrap(
+                cxn, width=78, initial_indent=" * ",
+                subsequent_indent="     ")) + "\n"
+
+        out += f"\nOutputs:\n"
+        for i in range(len(self.output_labels)):
+            first = True
+            cxn = f"{self.output_labels[i]} <- "
+            if np.any(self.output_map[i]):
+                for j in range(len(inpout_list)):
+                    if self.output_map[i, j]:
+                        cxn += cxn_string(
+                            output_list[j], self.output_map[i, j], first)
+                        first = False
+                out += "\n".join(textwrap.wrap(
+                    cxn, width=78, initial_indent=" * ",
+                    subsequent_indent="     ")) + "\n"
+
+        return out[:-1]
+
     def _update_params(self, params, warning=False):
         for sys in self.syslist:
             local = sys.params.copy()   # start with system parameters

control/statesp.py

@@ -379,8 +379,8 @@ def _remove_useless_states(self):
     def __str__(self):
         """Return string representation of the state space system."""
         string = f"{InputOutputSystem.__str__(self)}\n\n"
-        string += "\n".join([
-            "{} = {}\n".format(Mvar,
+        string += "\n\n".join([
+            "{} = {}".format(Mvar,
                                "\n    ".join(str(M).splitlines()))
             for Mvar, M in zip(["A", "B", "C", "D"],
                                [self.A, self.B, self.C, self.D])])

control/tests/nlsys_test.py

@@ -196,3 +196,51 @@ def test_ss2io():
         with pytest.raises(ValueError, match=r"new .* doesn't match"):
             kwargs = {attr: getattr(sys, 'n' + attr) - 1}
             nlsys = ct.nlsys(sys, **kwargs)
+
+
+def test_ICsystem_str():
+    sys1 = ct.rss(2, 2, 3, name='sys1', strictly_proper=True)
+    sys2 = ct.rss(2, 3, 2, name='sys2', strictly_proper=True)
+
+    with pytest.warns(UserWarning, match="Unused") as record:
+        sys = ct.interconnect(
+            [sys1, sys2], inputs=['r1', 'r2'], outputs=['y1', 'y2'],
+            connections=[
+                ['sys1.u[0]', '-sys2.y[0]', 'sys2.y[1]'],
+                ['sys1.u[1]', 'sys2.y[0]', '-sys2.y[1]'],
+                ['sys2.u[0]', 'sys2.y[0]', (0, 0, -1)],
+                ['sys2.u[1]', (1, 1, -2), (0, 1, -2)],
+            ],
+            inplist=['sys1.u[0]', 'sys1.u[1]'],
+            outlist=['sys2.y[0]', 'sys2.y[1]'])
+    assert len(record) == 2
+    assert str(record[0].message).startswith("Unused input")
+    assert str(record[1].message).startswith("Unused output")
+
+    ref = \
+        r"<LinearICSystem>: sys\[[\d]+\]" + "\n" + \
+        r"Inputs \(2\): \['r1', 'r2'\]" + "\n" + \
+        r"Outputs \(2\): \['y1', 'y2'\]" + "\n" + \
+        r"States \(4\): \['sys1_x\[0\].*'sys2_x\[1\]'\]" + "\n" + \
+        "\n" + \
+        r"A = \[\[.*\]\]" + "\n\n" + \
+        r"B = \[\[.*\]\]" + "\n\n" + \
+        r"C = \[\[.*\]\]" + "\n\n" + \
+        r"D = \[\[.*\]\]" + "\n" + \
+        "\n" + \
+        r"Subsystems \(2\):" + "\n" + \
+        r" \* <StateSpace sys1: \[.*\] -> \['y\[0\]', 'y\[1\]']>" + "\n" + \
+        r" \* <StateSpace sys2: \['u\[0\]', 'u\[1\]'] -> \[.*\]>" + "\n" + \
+        "\n" + \
+        r"Connections:" + "\n" + \
+        r" \* sys1.u\[0\] <- -sys2.y\[0\] \+ sys2.y\[1\] \+ r1" + "\n" + \
+        r" \* sys1.u\[1\] <- sys2.y\[0\] - sys2.y\[1\] \+ r2" + "\n" + \
+        r" \* sys1.u\[2\] <-" + "\n" + \
+        r" \* sys2.u\[0\] <- -sys1.y\[0\] \+ sys2.y\[0\]" + "\n" + \
+        r" \* sys2.u\[1\] <- -2.0 \* sys1.y\[1\] - 2.0 \* sys2.y\[1\]" + \
+        "\n\n" + \
+        r"Outputs:" + "\n" + \
+        r" \* y1 <- sys2.y\[0\]" + "\n" + \
+        r" \* y2 <- sys2.y\[1\]"
+
+    assert re.match(ref, str(sys), re.DOTALL)

control/tests/statesp_test.py

@@ -779,7 +779,7 @@ def test_str(self, sys322):
                 "     [ 1.  4.  3.]]\n"
                 "\n"
                 "D = [[-2.  4.]\n"
-                "     [ 0.  1.]]\n")
+                "     [ 0.  1.]]")
         assert str(tsys) == tref
         tsysdtunspec = StateSpace(
             tsys.A, tsys.B, tsys.C, tsys.D, True, name=tsys.name)