DeepOnet implementation, LabelTensor modification

* Implementing standard DeepOnet (trunk/branch net)
* Implementing multiple reduction/ average techniques
* Small change  LabelTensor __getitem__ for handling list
This commit is contained in:
Dario Coscia
2023-09-06 12:40:21 +02:00
committed by Nicola Demo
parent 15ecaacb7c
commit b029f18c49
3 changed files with 140 additions and 154 deletions

View File

@@ -212,8 +212,11 @@ class LabelTensor(torch.Tensor):
if selected_lt.ndim == 1:
selected_lt = selected_lt.reshape(-1, 1)
if hasattr(self, 'labels'):
selected_lt.labels = self.labels[index[1]]
if isinstance(index[1], list):
selected_lt.labels = [self.labels[i] for i in index[1]]
else:
selected_lt.labels = self.labels[index[1]]
return selected_lt
def __len__(self) -> int:

View File

@@ -1,60 +1,9 @@
"""Module for DeepONet model"""
import logging
from functools import partial, reduce
import torch
import torch.nn as nn
from ..utils import check_consistency, is_function
from functools import partial, reduce
from pina import LabelTensor
from pina.model import FeedForward
from pina.utils import is_function
def check_combos(combos, variables):
"""
Check that the given combinations are subsets (overlapping
is allowed) of the given set of variables.
:param iterable(iterable(str)) combos: Combinations of variables.
:param iterable(str) variables: Variables.
"""
for combo in combos:
for variable in combo:
if variable not in variables:
raise ValueError(
f"Combinations should be (overlapping) subsets of input variables, {variable} is not an input variable"
)
def spawn_combo_networks(
combos, layers, output_dimension, func, extra_feature, bias=True
):
"""
Spawn internal networks for DeepONet based on the given combos.
:param iterable(iterable(str)) combos: Combinations of variables.
:param iterable(int) layers: Size of hidden layers.
:param int output_dimension: Size of the output layer of the networks.
:param func: Nonlinearity.
:param extra_feature: Extra feature to be considered by the networks.
:param bool bias: Whether to consider bias or not.
"""
if is_function(extra_feature):
extra_feature_func = lambda _: extra_feature
else:
extra_feature_func = extra_feature
return [
FeedForward(
layers=layers,
input_variables=tuple(combo),
output_variables=output_dimension,
func=func,
extra_features=extra_feature_func(combo),
bias=bias,
)
for combo in combos
]
class DeepONet(torch.nn.Module):
@@ -70,14 +19,32 @@ class DeepONet(torch.nn.Module):
<https://doi.org/10.1038/s42256-021-00302-5>`_
"""
def __init__(self, nets, output_variables, aggregator="*", reduction="+"):
def __init__(self,
branch_net,
trunk_net,
input_indeces_branch_net,
input_indeces_trunk_net,
aggregator="*",
reduction="+"):
"""
:param iterable(torch.nn.Module) nets: Internal DeepONet networks
(branch and trunk in the original DeepONet).
:param list(str) output_variables: the list containing the labels
corresponding to the components of the output computed by the
model.
:param torch.nn.Module branch_net: The neural network to use as branch
model. It has to take as input a :class:`LabelTensor`
or :class:`torch.Tensor`. The number of dimensions of the output has
to be the same of the ``trunk_net``.
:param torch.nn.Module trunk_net: The neural network to use as trunk
model. It has to take as input a :class:`LabelTensor`
or :class:`torch.Tensor`. The number of dimensions of the output
has to be the same of the ``branch_net``.
:param list(int) | list(str) input_indeces_branch_net: List of indeces
to extract from the input variable in the forward pass for the
branch net. If a list of ``int`` is passed, the corresponding columns
of the inner most entries are extracted. If a list of ``str`` is passed
the variables of the corresponding :class:`LabelTensor` are extracted.
:param list(int) | list(str) input_indeces_trunk_net: List of indeces
to extract from the input variable in the forward pass for the
trunk net. If a list of ``int`` is passed, the corresponding columns
of the inner most entries are extracted. If a list of ``str`` is passed
the variables of the corresponding :class:`LabelTensor` are extracted.
:param str | callable aggregator: Aggregator to be used to aggregate
partial results from the modules in `nets`. Partial results are
aggregated component-wise. See
@@ -87,49 +54,66 @@ class DeepONet(torch.nn.Module):
the aggregated result of the modules in `nets` to the desired output
dimension. See :py:obj:`pina.model.deeponet.DeepONet._symbol_functions` for the available default
reductions.
:Example:
>>> branch = FFN(input_variables=['a', 'c'], output_variables=20)
>>> trunk = FFN(input_variables=['b'], output_variables=20)
>>> onet = DeepONet(nets=[trunk, branch], output_variables=output_vars)
>>> branch_net = FeedForward(input_dimensons=1, output_dimensions=10)
>>> trunk_net = FeedForward(input_dimensons=1, output_dimensions=10)
>>> model = DeepONet(branch_net=branch_net,
... trunk_net=trunk_net,
... input_indeces_branch_net=['x'],
... input_indeces_trunk_net=['t'],
... reduction='+',
... aggregator='*')
>>> model
DeepONet(
(trunk_net): FeedForward(
(extra_features): Sequential()
(trunk_net): FeedForward(
(model): Sequential(
(0): Linear(in_features=1, out_features=20, bias=True)
(1): Tanh()
(2): Linear(in_features=20, out_features=20, bias=True)
(3): Tanh()
(4): Linear(in_features=20, out_features=20, bias=True)
(4): Linear(in_features=20, out_features=10, bias=True)
)
)
(branch_net): FeedForward(
(extra_features): Sequential()
)
(branch_net): FeedForward(
(model): Sequential(
(0): Linear(in_features=2, out_features=20, bias=True)
(0): Linear(in_features=1, out_features=20, bias=True)
(1): Tanh()
(2): Linear(in_features=20, out_features=20, bias=True)
(3): Tanh()
(4): Linear(in_features=20, out_features=20, bias=True)
(4): Linear(in_features=20, out_features=10, bias=True)
)
)
)
)
"""
super().__init__()
self.output_variables = output_variables
self.output_dimension = len(output_variables)
# check type consistency
check_consistency(input_indeces_branch_net, (str, int))
check_consistency(input_indeces_trunk_net, (str, int))
check_consistency(branch_net, torch.nn.Module)
check_consistency(trunk_net, torch.nn.Module)
self._init_aggregator(aggregator, n_nets=len(nets))
hidden_size = nets[0].model[-1].out_features
self._init_reduction(reduction, hidden_size=hidden_size)
# check trunk branch nets consistency
trunk_out_dim = trunk_net.layers[-1].out_features
branch_out_dim = branch_net.layers[-1].out_features
if trunk_out_dim != branch_out_dim:
raise ValueError('Branch and trunk networks have not the same '
'output dimension.')
if not DeepONet._all_nets_same_output_layer_size(nets):
raise ValueError("All networks should have the same output size")
self._nets = torch.nn.ModuleList(nets)
logging.info("Combo DeepONet children: %s", list(self.children()))
self.scale = torch.nn.Parameter(torch.tensor([1.0]))
self.trasl = torch.nn.Parameter(torch.tensor([0.0]))
# assign trunk and branch net with their input indeces
self.trunk_net = trunk_net
self._trunk_indeces = input_indeces_trunk_net
self.branch_net = branch_net
self._branch_indeces = input_indeces_branch_net
# initializie aggregation
self._init_aggregator(aggregator=aggregator)
self._init_reduction(reduction=reduction)
# scale and translation
self._scale = torch.nn.Parameter(torch.tensor([1.0]))
self._trasl = torch.nn.Parameter(torch.tensor([0.0]))
@staticmethod
def _symbol_functions(**kwargs):
@@ -144,59 +128,39 @@ class DeepONet(torch.nn.Module):
"min": lambda x: torch.min(x, **kwargs).values,
"max": lambda x: torch.max(x, **kwargs).values,
}
def _init_aggregator(self, aggregator, n_nets):
def _init_aggregator(self, aggregator):
aggregator_funcs = DeepONet._symbol_functions(dim=2)
if aggregator in aggregator_funcs:
aggregator_func = aggregator_funcs[aggregator]
elif isinstance(aggregator, nn.Module) or is_function(aggregator):
aggregator_func = aggregator
elif aggregator == "linear":
aggregator_func = nn.Linear(n_nets, len(self.output_variables))
else:
raise ValueError(f"Unsupported aggregation: {str(aggregator)}")
self._aggregator = aggregator_func
logging.info("Selected aggregator: %s", str(aggregator_func))
# test the aggregator
test = self._aggregator(torch.ones((20, 3, n_nets)))
if test.ndim < 2 or tuple(test.shape)[:2] != (20, 3):
raise ValueError(
f"Invalid aggregator output shape: {(20, 3, n_nets)} -> {test.shape}"
)
def _init_reduction(self, reduction, hidden_size):
reduction_funcs = DeepONet._symbol_functions(dim=2)
def _init_reduction(self, reduction):
reduction_funcs = DeepONet._symbol_functions(dim=-1)
if reduction in reduction_funcs:
reduction_func = reduction_funcs[reduction]
elif isinstance(reduction, nn.Module) or is_function(reduction):
reduction_func = reduction
elif reduction == "linear":
reduction_func = nn.Linear(hidden_size, len(self.output_variables))
else:
raise ValueError(f"Unsupported reduction: {reduction}")
self._reduction = reduction_func
logging.info("Selected reduction: %s", str(reduction))
# test the reduction
test = self._reduction(torch.ones((20, 3, hidden_size)))
if test.ndim < 2 or tuple(test.shape)[:2] != (20, 3):
msg = f"Invalid reduction output shape: {(20, 3, hidden_size)} -> {test.shape}"
raise ValueError(msg)
@staticmethod
def _all_nets_same_output_layer_size(nets):
size = nets[0].layers[-1].out_features
return all((net.layers[-1].out_features == size for net in nets[1:]))
@property
def input_variables(self):
"""The input variables of the model"""
nets_input_variables = map(lambda net: net.input_variables, self._nets)
return reduce(sum, nets_input_variables)
def _get_vars(self, x, indeces):
if isinstance(indeces[0], str):
check_consistency(x, LabelTensor)
return x.extract(indeces)
elif isinstance(indeces[0], int):
return x[..., indeces]
else:
raise RuntimeError('Not able to extract right indeces for tensor.')
def forward(self, x):
"""
Defines the computation performed at every call.
@@ -206,23 +170,18 @@ class DeepONet(torch.nn.Module):
:rtype: LabelTensor
"""
nets_outputs = tuple(
net(x.extract(net.input_variables)) for net in self._nets
)
# torch.dstack(nets_outputs): (batch_size, net_output_size, n_nets)
aggregated = self._aggregator(torch.dstack(nets_outputs))
# net_output_size = output_variables * hidden_size
aggregated_reshaped = aggregated.view(
(len(x), len(self.output_variables), -1)
)
output_ = self._reduction(aggregated_reshaped)
output_ = torch.squeeze(torch.atleast_3d(output_), dim=2)
# forward pass
branch_output = self.branch_net(self._get_vars(x, self._branch_indeces))
trunk_output = self.trunk_net(self._get_vars(x, self._trunk_indeces))
assert output_.shape == (len(x), len(self.output_variables))
# aggregation
aggregated = self._aggregator(torch.dstack((branch_output, trunk_output)))
output_ = output_.as_subclass(LabelTensor)
output_.labels = self.output_variables
# reduce
output_ = self._reduction(aggregated).reshape(-1, 1)
output_ *= self.scale
output_ += self.trasl
return output_
# scale and translate
output_ *= self._scale
output_ += self._trasl
return output_