def _get_model_smoothing_task(self, tasks=None):
if tasks is None:
tasks = {}
if max(self.roughness_decay_smoothing_length) > 0.0:
# We either smooth the physical model and then map the results back
# to the internal parameterization
# Or we smooth the relative perturbations with respect to
if self.roughness_decay_type == "absolute":
model_to_smooth = self.model_path
else:
model_to_smooth = os.path.join(
self.regularization_dir,
f"relative_perturbation_{self.iteration_name}.h5",
)
shutil.copy(self.model_path, model_to_smooth)
write_xdmf(model_to_smooth)
# relative perturbation = (latest - start) / start
theta_prev = self.get_h5_data(self.model_path)
theta_0 = self.get_h5_data(
self._get_path_for_iteration(0, self.model_path))
theta_prev[theta_0 != 0] = (
theta_prev[theta_0 != 0] / theta_0[theta_0 != 0] - 1)
self.set_h5_data(model_to_smooth, theta_prev)
tasks["roughness_decay"] = {
"reference_model": str(self.comm.lasif.get_master_model()),
"model_to_smooth": str(model_to_smooth),
"smoothing_lengths": self.roughness_decay_smoothing_length,
"smoothing_parameters": self.parameters,
"output_location": str(self.smoothed_model_path),
}
return tasks
def perform_smoothing(self):
tasks = self._get_model_smoothing_task()
if max(self.update_smoothing_length) > 0.0:
tasks["smooth_raw_update"] = {
"reference_model": str(self.comm.lasif.get_master_model()),
"model_to_smooth": str(self.raw_update_path),
"smoothing_lengths": self.update_smoothing_length,
"smoothing_parameters": self.parameters,
"output_location": str(self.smooth_update_path),
}
if len(tasks.keys()) > 0:
reg_helper = RegularizationHelper(
comm=self.comm,
iteration_name=self.iteration_name,
tasks=tasks)
reg_helper.monitor_tasks()
else:
raise InversionsonError(
"We require some sort of smoothing in Adam Optimization")
# Write XDFMs
if max(self.update_smoothing_length) > 0.0:
write_xdmf(self.smooth_update_path)
if max(self.roughness_decay_smoothing_length) > 0.0:
write_xdmf(self.smoothed_model_path)
def _compute_raw_update(self):
"""Computes the raw update"""
self.print("SGD with Momentum: Computing raw update...",
line_above=True)
# Read task toml
iteration_number = self.task_dict["iteration_number"] + 1
indices = self.get_parameter_indices(self.raw_gradient_path)
# scale the gradients, because they can be tiny and this leads to issues
g_t = self.get_h5_data(self.raw_gradient_path) * self.grad_scaling_fac
if np.sum(np.isnan(g_t)) > 1:
raise Exception("NaNs were found in the raw gradient."
"Something must be wrong.")
if iteration_number == 1: # Initialize moments if needed
shutil.copy(self.raw_gradient_path, self.moment_path)
write_xdmf(self.moment_path)
with h5py.File(self.moment_path, "r+") as h5:
data = h5["MODEL/data"]
# initialize with zeros
for i in indices:
data[:, i, :] = np.zeros_like(data[:, i, :])
v_t = self.beta * self.get_h5_data(
self.moment_path) + (1 - self.beta) * g_t
# Store first moment
shutil.copy(
self.moment_path,
self._get_path_for_iteration(self.iteration_number + 1,
self.moment_path),
)
self.set_h5_data(
self._get_path_for_iteration(self.iteration_number + 1,
self.moment_path),
v_t,
)
# Correct bias
v_t = v_t / (1 - self.beta**(self.iteration_number + 1))
update = self.alpha * v_t
if np.sum(np.isnan(update)) > 1:
raise Exception("NaNs were found in the raw update."
"Check if the gradient is not excessively small")
# Write raw update to file for smoothing
shutil.copy(self.raw_gradient_path, self.raw_update_path)
self.set_h5_data(self.raw_update_path, update)
def update_model(self, verbose):
"""
This task takes the raw gradient and does all the regularisation and everything
to update the model.
"""
if self.comm.project.meshes == "multi-mesh":
self.comm.lasif.move_gradient_to_cluster()
if not self.task_dict["summing_completed"]:
grad_summer = GradientSummer(comm=self.comm)
grad_summer.sum_gradients(
events=self.comm.project.non_val_events_in_iteration,
output_location=self.raw_gradient_path,
batch_average=True,
sum_vpv_vph=True,
store_norms=True,
)
write_xdmf(self.raw_gradient_path)
self.task_dict["summing_completed"] = True
self._update_task_file()
else:
self.print("Summing already done")
if not self.task_dict["raw_update_completed"]:
self._update_model(raw=True, smooth=False, verbose=verbose)
self.task_dict["raw_update_completed"] = True
self._update_task_file()
else:
self.print("Raw updating already completed")
if not self.task_dict["smoothing_completed"]:
self.perform_smoothing()
self.task_dict["smoothing_completed"] = True
self._update_task_file()
else:
self.print("Smoothing already done")
if not self.task_dict["smooth_update_completed"]:
self._update_model(raw=False, smooth=True, verbose=verbose)
self.task_dict["smooth_update_completed"] = True
self._update_task_file()
else:
self.print("Smooth updating already completed")
if not self.task_dict["iteration_finalized"]:
self._finalize_iteration(verbose=verbose)
self.task_dict["iteration_finalized"] = True
self._update_task_file()
else:
self.print("Iteration already finalized")
self.finish_task()
def finish_task(self):
paths = ["raw_update_path", "model", "raw_gradient_path"]
if max(self.update_smoothing_length) > 0.0:
paths.append("smooth_update_path")
if max(self.roughness_decay_smoothing_length) > 0.0:
paths.append("smoothed_model_path")
complete_checks = [
"smoothing_completed",
"gradient_completed",
"iteration_finalized",
"forward_submitted",
"raw_update_completed",
"smooth_update_completed",
"misfit_completed",
"summing_completed",
"validated:",
]
for path in paths:
if path in self.task_dict.keys():
if not os.path.exists(self.task_dict[path]):
raise InversionsonError(
f"Trying to finish task but it can't find {self.task_dict[path]}"
)
for complete_check in complete_checks:
if complete_check in self.task_dict.keys():
if not self.task_dict[complete_check]:
raise InversionsonError(
f"Trying to finish task but {complete_check} is not completed"
)
self.task_dict["finished"] = True
if self.task_dict["task"] == "update_model":
self._update_task_file()
target_location = self._get_path_for_iteration(
self.iteration_number + 1, self.model_path)
# Moving the new model into its place, moves the iteration property to the next one.
shutil.move(
self.tmp_model_path,
target_location,
)
write_xdmf(target_location)
else:
self._update_task_file()
def set_h5_data(self, filename, data, create_xdmf=True):
"""Writes the data with shape [:, indices :]. Requires existing file."""
if not os.path.exists(filename):
raise Exception("only works on existing files.")
indices = self.get_parameter_indices(filename)
with h5py.File(filename, "r+") as h5:
dat = h5["MODEL/data"]
data_copy = dat[:, :, :].copy()
# avoid writing the file many times. work on array in memory
for i in range(len(indices)):
data_copy[:, indices[i], :] = data[:, i, :]
# writing only works in sorted order. This sort can only happen after
# the above executed to preserve the ordering that data came in
indices.sort()
dat[:, indices, :] = data_copy[:, indices, :]
if create_xdmf:
write_xdmf(filename)
def _init_directories(self):
"""
Build directory structure.
"""
folders = [
self.model_dir,
self.average_model_dir,
self.raw_gradient_dir,
self.moment_dir,
self.raw_update_dir,
self.smooth_update_dir,
self.task_dir,
self.regularization_dir,
self.smoothed_model_dir,
self.gradient_norm_dir,
]
for folder in folders:
if not os.path.exists(folder):
os.mkdir(folder)
shutil.copy(self.initial_model, self.model_path)
write_xdmf(self.model_path)
def _compute_raw_update(self):
"""Computes the raw update"""
self.print("Adam: Computing raw update...", line_above=True)
# Read task toml
iteration_number = self.task_dict["iteration_number"] + 1
indices = self.get_parameter_indices(self.raw_gradient_path)
# scale the gradients, because they can be tiny and this leads to issues
g_t = self.get_h5_data(self.raw_gradient_path) * self.grad_scaling_fac
if np.sum(np.isnan(g_t)) > 1:
raise Exception("NaNs were found in the raw gradient."
"Something must be wrong.")
if iteration_number == 1: # Initialize moments if needed
shutil.copy(self.raw_gradient_path, self.first_moment_path)
write_xdmf(self.first_moment_path)
with h5py.File(self.first_moment_path, "r+") as h5:
data = h5["MODEL/data"]
# initialize with zeros
for i in indices:
data[:, i, :] = np.zeros_like(data[:, i, :])
# Also initialize second moments with zeros
shutil.copy(self.first_moment_path, self.second_moment_path)
write_xdmf(self.second_moment_path)
m_t = (self.beta_1 * self.get_h5_data(self.first_moment_path) +
(1 - self.beta_1) * g_t)
# Store first moment
shutil.copy(
self.first_moment_path,
self._get_path_for_iteration(self.iteration_number + 1,
self.first_moment_path),
)
self.set_h5_data(
self._get_path_for_iteration(self.iteration_number + 1,
self.first_moment_path),
m_t,
)
# v_t was sometimes becoming too small, so enforce double precision
v_t = self.beta_2 * self.get_h5_data(
self.second_moment_path) + (1 - self.beta_2) * (g_t**2)
# Store second moment
shutil.copy(
self.second_moment_path,
self._get_path_for_iteration(self.iteration_number + 1,
self.second_moment_path),
)
self.set_h5_data(
self._get_path_for_iteration(self.iteration_number + 1,
self.second_moment_path),
v_t,
)
# Correct bias
m_t = m_t / (1 - self.beta_1**(self.iteration_number + 1))
v_t = v_t / (1 - self.beta_2**(self.iteration_number + 1))
# ensure e is sufficiently small, even for the small gradient values
# that we typically have.
e = self.epsilon * np.mean(np.sqrt(v_t))
update = self.alpha * m_t / (np.sqrt(v_t) + e)
max_upd = np.max(np.abs(update))
self.print(f"Max raw model update: {max_upd}")
if max_upd > 3.0 * self.alpha:
raise Exception("Raw update seems a bit large")
if np.sum(np.isnan(update)) > 1:
raise Exception("NaNs were found in the raw update."
"Check if the gradient is not excessively small")
# Write raw update to file for smoothing
shutil.copy(self.raw_gradient_path, self.raw_update_path)
self.set_h5_data(self.raw_update_path, update)
