diff --git a/control/iosys.py b/control/iosys.py
index 9b33d2161..a32978b58 100644
--- a/control/iosys.py
+++ b/control/iosys.py
@@ -2138,10 +2138,15 @@ def rootfun(z):
dx = sys._rhs(t, x, u) - dx0
if dtime:
dx -= x # TODO: check
- dy = sys._out(t, x, u) - y0
- # Map the results into the constrained variables
- return np.concatenate((dx[deriv_vars], dy[output_vars]), axis=0)
+ # If no y0 is given, don't evaluate the output function
+ if y0 is None:
+ return dx[deriv_vars]
+ else:
+ dy = sys._out(t, x, u) - y0
+
+ # Map the results into the constrained variables
+ return np.concatenate((dx[deriv_vars], dy[output_vars]), axis=0)
# Set the initial condition for the root finding algorithm
z0 = np.concatenate((x[state_vars], u[input_vars]), axis=0)
diff --git a/control/tests/iosys_test.py b/control/tests/iosys_test.py
index 7d3b9fee9..003c43d03 100644
--- a/control/tests/iosys_test.py
+++ b/control/tests/iosys_test.py
@@ -822,6 +822,17 @@ def test_find_eqpts(self, tsys):
np.testing.assert_array_almost_equal(
nlsys_full._rhs(0, xeq, ueq)[-4:], np.zeros((4,)), decimal=5)
+ # The same test as previous, but now all constraints are in the state vector
+ nlsys_full = ios.NonlinearIOSystem(pvtol_full, None)
+ xeq, ueq, result = ios.find_eqpt(
+ nlsys_full, [0, 0, 0.1, 0.1, 0, 0], [0.01, 4*9.8],
+ idx=[2, 3, 4, 5], ix=[0, 1, 2, 3], return_result=True)
+ assert result.success
+ np.testing.assert_array_almost_equal(
+ nlsys_full._out(0, xeq, ueq)[[2, 3]], [0.1, 0.1], decimal=5)
+ np.testing.assert_array_almost_equal(
+ nlsys_full._rhs(0, xeq, ueq)[-4:], np.zeros((4,)), decimal=5)
+
# Fix one input and vary the other
nlsys_full = ios.NonlinearIOSystem(pvtol_full, None)
xeq, ueq, result = ios.find_eqpt(
pFad - Phonifier reborn
Pfad - The Proxy pFad of © 2024 Garber Painting. All rights reserved.
Note: This service is not intended for secure transactions such as banking, social media, email, or purchasing. Use at your own risk. We assume no liability whatsoever for broken pages.
Alternative Proxies:
Alternative Proxy
pFad Proxy
pFad v3 Proxy
pFad v4 Proxy