def test_import_export(self):
sys = ctrl.tf([1], [100, 1])
sim_duration = 2000
time = np.zeros(sim_duration)
i = 0
while (i < sim_duration):
time[i] = i
i += 1
_, output = ctrl.step_response(sys, time)
m = ps.FsrModel(output, t=time)
# testing our model with a test signal
test_sgnl_len = int(2500)
u = np.zeros(test_sgnl_len)
for i in range(test_sgnl_len):
u[i] = 1
time = np.zeros(test_sgnl_len)
for i in range(test_sgnl_len):
time[i] = i
_, comp, _ = ctrl.forced_response(sys, time, u)
# 'rb' and 'wb' to avoid problems under Windows!
with open("temp", "w") as fh:
ps.export_csv(m, fh)
with open("temp", "r") as fh:
m = ps.import_csv(fh)
os.remove("temp")
_, y = ps.forced_response(m, time, u)
self.assertTrue(np.allclose(y, comp, rtol=1e-2), "import/export broke")
def creation_example():
"""Example for creation of a FSR model with python-control."""
# creating a step response for our model
sys = ctrl.tf([1], [100, 1])
sim_duration = 2000
time = np.arange(sim_duration)
_, output = ctrl.step_response(sys, time)
# creating the model
model = ps.FsrModel(output, t=time)
# creating a test input signal
u = np.ones(sim_duration)
for i in range(len(u)):
if i < 500:
u[i] = 0.001 * i
# getting response from our model
t1, y1 = ps.forced_response(model, time, u)
# simulating a reference with control
t2, y2, _ = ctrl.forced_response(sys, time, u)
# show everything
ax = plt.subplot(111)
plt.plot(t1, y1, label="Model response")
plt.plot(t2, y2, label="Reference response")
plt.plot(t1, u, label="Input signal")
ax.legend()
plt.title("pystrem example")
plt.show()
def test_IT2_forced_response(self):
sys = ctrl.tf([100], [50, 1000, 150, 0]) # IT2
_, o = ctrl.step_response(sys, self.time)
m = ps.FsrModel(o, t=self.time, optimize=False)
_, y = ps.forced_response(m, self.t, self.u)
_, o, _ = ctrl.forced_response(sys, self.t, self.u)
self.assertTrue(np.allclose(y, o, rtol=1e-2), "it2 response broke")
def test_PT2_forced_response(self):
sys = ctrl.tf([1], [1000, 10, 1]) # PT2 with overshooting
_, o = ctrl.step_response(sys, self.time)
m = ps.FsrModel(o, t=self.time)
_, y = ps.forced_response(m, self.t, self.u)
_, o, _ = ctrl.forced_response(sys, self.t, self.u)
self.assertTrue(np.allclose(y, o, rtol=1e-2), "pt2 response broke")
def test_all_pass_forced_response(self):
sys = ctrl.tf([-50, 1], [1000, 10, 1]) # all-pass
_, o = ctrl.step_response(sys, self.time)
m = ps.FsrModel(o, t=self.time)
_, y = ps.forced_response(m, self.t, self.u)
_, o, _ = ctrl.forced_response(sys, self.t, self.u)
self.assertTrue(np.allclose(y, o, rtol=1e-1),
"all-pass response broke")
def test_crazy_system_forced_response(self):
# numerator: (s+50)(s-2)((s+8)²+45)(s²+100))
# denominator: (s+2)(s+3)(s+3)(s+4)((s+1.5)²+5)((s+3)²+2)((s+0.5)²+3)
# ((s+4)²+30)
sys = ctrl.tf([1, 64, 877, 10032, 66800, 363200, -1090000], [
1, 30, 443.5, 4140, 26677.6, 124311, 430648, 1.12577e6, 2.22475e6,
3.28564e6, 3.49963e6, 2.45298e6, 858429
])
time = np.arange(0, 60, 0.01)
u = np.ones(len(time))
for i in range(len(u)):
if i < 25 / 0.01:
u[i] = 0.5
_, o = ctrl.step_response(sys, time)
m = ps.FsrModel(o, time)
_, y = ps.forced_response(m, time, u)
_, o, _ = ctrl.forced_response(sys, time, u)
self.assertTrue(np.allclose(y, o, rtol=1e-2), "crazy response broke")