def test_solve_setpoint_unsteady(self):
controller = self.make_controller()
time = controller.time
t0 = time.first()
setpoint = [
(controller.mod.flow_in[t0], 3.0),
(controller.mod.conc[t0, 'A'], 5.0),
]
weights = [
(controller.mod.flow_in[t0], 1.0),
(controller.mod.conc[t0, 'A'], 1.0),
]
controller.add_setpoint_objective(setpoint, weights)
controller.mod.flow_in[:].set_value(3.0)
initialize_t0(controller.mod)
dof_prior = degrees_of_freedom(controller)
controller.solve_setpoint(solver, require_steady=False)
dof_post = degrees_of_freedom(controller)
assert dof_prior == dof_post
assert controller.differential_vars[0].setpoint == \
pytest.approx(5.0, abs=1e-3)
assert controller.differential_vars[1].setpoint == \
pytest.approx(7.11, abs=1e-3)
assert controller.algebraic_vars[0].setpoint == \
pytest.approx(3.0, abs=1e-3)
assert controller.algebraic_vars[1].setpoint == \
pytest.approx(-5.0, abs=1e-3)
assert controller.algebraic_vars[2].setpoint == \
pytest.approx(5.0, abs=1e-3)
assert controller.input_vars[0].setpoint == \
pytest.approx(3.0, abs=1e-3)
def test_init_samples_by_element(self):
blk = self.make_block()
time = blk.time
blk.mod.flow_in[:].set_value(3.0)
initialize_t0(blk.mod)
copy_values_forward(blk.mod)
blk.mod.flow_in[:].set_value(2.0)
blk.set_sample_time(0.5)
blk.initialize_samples_by_element((1,2), solver)
t0 = time.first()
tl = time.last()
vectors = blk.vectors
assert vectors.input[0,tl].value == 2.0
assert vectors.differential[0,tl].value == pytest.approx(3.185595567867036)
assert vectors.differential[1,tl].value == pytest.approx(1.1532474073395755)
assert vectors.derivative[0,tl].value == pytest.approx(0.44321329639889284)
assert vectors.derivative[1,tl].value == pytest.approx(0.8791007531878847)
blk.vectors.input.set_setpoint(3.0)
blk.initialize_samples_by_element(1, solver, input_option=InputOption.SETPOINT)
blk.initialize_samples_by_element(2, solver, input_option=InputOption.SETPOINT)
for t in time:
if t == t0:
assert vectors.input[0,t].value == 2.0
else:
assert vectors.input[0,t].value == 3.0
assert vectors.differential[0,tl].value == pytest.approx(3.7037037037037037)
assert vectors.differential[1,tl].value == pytest.approx(1.0746896480968502)
assert vectors.derivative[0,tl].value == pytest.approx(0.1851851851851849)
assert vectors.derivative[1,tl].value == pytest.approx(0.47963475941315314)
def test_initialize_only_measurement_input(self):
model = make_model(horizon=1, nfe=2)
time = model.time
t0 = time.first()
inputs = [model.flow_in]
measurements = [
pyo.Reference(model.conc[:, 'A']),
pyo.Reference(model.conc[:, 'B']),
]
category_dict = {
VC.INPUT: inputs,
VC.MEASUREMENT: measurements,
}
db = DynamicBlock(
model=model,
time=time,
category_dict={None: category_dict},
)
db.construct()
db.set_sample_time(0.5)
db.mod.flow_in[:].set_value(3.0)
initialize_t0(db.mod)
copy_values_forward(db.mod)
db.mod.flow_in[:].set_value(2.0)
# Don't need to know any of the special categories to initialize
# by element. This is only because we have an implicit discretization.
db.initialize_by_solving_elements(solver)
t0 = time.first()
tl = time.last()
vectors = db.vectors
assert vectors.input[0, tl].value == 2.0
assert vectors.measurement[0, tl].value == pytest.approx(
3.185595567867036)
assert vectors.measurement[1, tl].value == pytest.approx(
1.1532474073395755)
assert model.dcdt[tl, 'A'].value == pytest.approx(0.44321329639889284)
assert model.dcdt[tl, 'B'].value == pytest.approx(0.8791007531878847)
def test_add_setpoint_objective(self):
controller = self.make_controller()
time = controller.time
t0 = time.first()
setpoint = [
(controller.mod.flow_in[t0], 3.0),
]
weights = [
(controller.mod.flow_in[t0], 2.0),
]
controller.mod.flow_in[:].set_value(3.0)
initialize_t0(controller.mod)
controller.add_setpoint_objective(setpoint, weights)
assert hasattr(controller, 'setpoint_objective')
pred_obj_expr = (2.0 * (controller.mod.flow_in[t0] - 3.0)**2)
obj_expr = controller.setpoint_objective.expr
assert pyo.value(pred_obj_expr) == pyo.value(obj_expr)
assert pred_obj_expr.to_string() == obj_expr.to_string()
controller.del_component(controller.setpoint_objective)
setpoint = [
(controller.mod.flow_in[t0], 3.0),
(controller.mod.conc[t0, 'A'], 1.5),
]
weights = [
(controller.mod.flow_in[t0], 1.0),
(controller.mod.conc[t0, 'A'], 5.0),
]
controller.add_setpoint_objective(setpoint, weights)
pred_obj_expr = (1.0 * (controller.mod.flow_in[t0] - 3.0)**2 + 5.0 *
(controller.mod.conc[t0, 'A'] - 1.5)**2)
obj_expr = controller.setpoint_objective.expr
assert pyo.value(pred_obj_expr) == pyo.value(obj_expr)
assert pred_obj_expr.to_string() == obj_expr.to_string()
def test_add_tracking_objective(self):
controller = self.make_controller()
time = controller.time
t0 = time.first()
setpoint = [
(controller.mod.flow_in[t0], 3.0),
]
weights = [
(controller.mod.flow_in[t0], 1.0),
]
controller.mod.flow_in[:].set_value(3.0)
initialize_t0(controller.mod)
copy_values_forward(controller.mod)
controller.add_setpoint_objective(setpoint, weights)
controller.solve_setpoint(solver)
# Re-initialize inputs so they are not at the setpoint
# for objective evaluation.
controller.mod.flow_in[:].set_value(2.5)
weights = [
(controller.mod.conc[t0, 'A'], 1),
(controller.mod.conc[t0, 'B'], 1),
(controller.mod.rate[t0, 'A'], 1),
(controller.mod.rate[t0, 'B'], 1),
(controller.mod.flow_out[t0], 1),
(controller.mod.flow_in[t0], 1),
]
# Construct predicted objective functions:
pred_obj = {i: 0. for i in range(1, 4)}
sample_points = controller.sample_points[1:]
sample_time = controller.sample_time
for v in controller.component_objects(DiffVar):
for t in sample_points:
pred_obj[1] += (v[t] - v.setpoint)**2
pred_obj[2] += (v[t] - v.setpoint)**2
pred_obj[3] += (v[t] - v.setpoint)**2
for v in controller.component_objects(AlgVar):
for t in sample_points:
pred_obj[3] += (v[t] - v.setpoint)**2
for v in controller.component_objects(InputVar):
for t in sample_points:
i_prev = time.find_nearest_index(t - sample_time,
tolerance=1e-8)
t_prev = time[i_prev]
pred_obj[1] += (v[t] - v.setpoint)**2
pred_obj[2] += (v[t] - v[t_prev])**2
pred_obj[3] += (v[t] - v[t_prev])**2
controller.add_tracking_objective(
weights,
control_penalty_type=ControlPenaltyType.ERROR,
state_ctypes=DiffVar,
)
assert pyo.value(controller.tracking_objective.expr == pred_obj[1])
assert pyo.value(controller.tracking_objective.expr) > 0
controller.del_component(controller.tracking_objective)
controller.add_tracking_objective(
weights,
control_penalty_type=ControlPenaltyType.ACTION,
state_ctypes=DiffVar,
)
assert pyo.value(controller.tracking_objective.expr == pred_obj[2])
assert pyo.value(controller.tracking_objective.expr) > 0
controller.del_component(controller.tracking_objective)
controller.add_tracking_objective(
weights,
control_penalty_type=ControlPenaltyType.ACTION,
state_ctypes=(DiffVar, AlgVar),
)
assert pyo.value(controller.tracking_objective.expr == pred_obj[3])
assert pyo.value(controller.tracking_objective.expr) > 0