update descfcn module for compatibility

murrayrm · murrayrm · commit 1d9fc80c8830 · 2021-02-10T22:02:09.000-08:00
diff --git a/control/descfcn.py b/control/descfcn.py
@@ -241,8 +241,9 @@ def describing_function_plot(
 
     """
     # Start by drawing a Nyquist curve
-    H_real, H_imag, H_omega = nyquist_plot(H, omega, plot=True, **kwargs)
-    H_vals = H_real + 1j * H_imag
+    count, contour = nyquist_plot(
+        H, omega, plot=True, return_contour=True, **kwargs)
+    H_omega, H_vals = contour.imag, H(contour)
 
     # Compute the describing function
     df = describing_function(F, A)
diff --git a/examples/describing_functions.ipynb b/examples/describing_functions.ipynb
@@ -369,7 +369,7 @@
     "amp = np.linspace(0.6, 5, 50)\n",
     "\n",
     "# Describing function plot\n",
-    "ct.describing_function_plot(H_multiple, F_backlash, amp, omega, mirror=False)"
+    "ct.describing_function_plot(H_multiple, F_backlash, amp, omega, mirror_style=False)"
    ]
   },
   {

Original file line number	Diff line number	Diff line change
`@@ -369,7 +369,7 @@`
`369`	`369`	`"amp = np.linspace(0.6, 5, 50)\n",`
`370`	`370`	`"\n",`
`371`	`371`	`"# Describing function plot\n",`
`372`		`- "ct.describing_function_plot(H_multiple, F_backlash, amp, omega, mirror=False)"`
	`372`	`+ "ct.describing_function_plot(H_multiple, F_backlash, amp, omega, mirror_style=False)"`
`373`	`373`	`]`
`374`	`374`	`},`
`375`	`375`	`{`