Files
PINA/pina/utils.py
Dario Coscia 9cae9a438f Update solvers (#434)
* Enable DDP training with batch_size=None and add validity check for split sizes
* Refactoring SolverInterfaces (#435)
* Solver update + weighting
* Updating PINN for 0.2
* Modify GAROM + tests
* Adding more versatile loggers
* Disable compilation when running on Windows
* Fix tests

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Co-authored-by: giovanni <giovanni.canali98@yahoo.it>
Co-authored-by: FilippoOlivo <filippo@filippoolivo.com>
2025-03-19 17:46:35 +01:00

133 lines
3.9 KiB
Python

"""Utils module."""
import types
import torch
from functools import reduce
from .label_tensor import LabelTensor
def check_consistency(object, object_instance, subclass=False):
"""Helper function to check object inheritance consistency.
Given a specific ``'object'`` we check if the object is
instance of a specific ``'object_instance'``, or in case
``'subclass=True'`` we check if the object is subclass
if the ``'object_instance'``.
:param (iterable or class object) object: The object to check the inheritance
:param Object object_instance: The parent class from where the object
is expected to inherit
:param str object_name: The name of the object
:param bool subclass: Check if is a subclass and not instance
:raises ValueError: If the object does not inherit from the
specified class
"""
if not isinstance(object, (list, set, tuple)):
object = [object]
for obj in object:
try:
if not subclass:
assert isinstance(obj, object_instance)
else:
assert issubclass(obj, object_instance)
except AssertionError:
raise ValueError(f"{type(obj).__name__} must be {object_instance}.")
def labelize_forward(forward, input_variables, output_variables):
"""
Wrapper decorator to allow users to enable or disable the use of
LabelTensors during the forward pass.
:param forward: The torch.nn.Module forward function.
:type forward: Callable
:param input_variables: The problem input variables.
:type input_variables: list[str] | tuple[str]
:param output_variables: The problem output variables.
:type output_variables: list[str] | tuple[str]
"""
def wrapper(x):
x = x.extract(input_variables)
output = forward(x)
# keep it like this, directly using LabelTensor(...) raises errors
# when compiling the code
output = output.as_subclass(LabelTensor)
output.labels = output_variables
return output
return wrapper
def merge_tensors(tensors): # name to be changed
if tensors:
return reduce(merge_two_tensors, tensors[1:], tensors[0])
raise ValueError("Expected at least one tensor")
def merge_two_tensors(tensor1, tensor2):
n1 = tensor1.shape[0]
n2 = tensor2.shape[0]
tensor1 = LabelTensor(tensor1.repeat(n2, 1), labels=tensor1.labels)
tensor2 = LabelTensor(tensor2.repeat_interleave(n1, dim=0),
labels=tensor2.labels)
return tensor1.append(tensor2)
def torch_lhs(n, dim):
"""Latin Hypercube Sampling torch routine.
Sampling in range $[0, 1)^d$.
:param int n: number of samples
:param int dim: dimensions of latin hypercube
:return: samples
:rtype: torch.tensor
"""
if not isinstance(n, int):
raise TypeError("number of point n must be int")
if not isinstance(dim, int):
raise TypeError("dim must be int")
if dim < 1:
raise ValueError("dim must be greater than one")
samples = torch.rand(size=(n, dim))
perms = torch.tile(torch.arange(1, n + 1), (dim, 1))
for row in range(dim):
idx_perm = torch.randperm(perms.shape[-1])
perms[row, :] = perms[row, idx_perm]
perms = perms.T
samples = (perms - samples) / n
return samples
def is_function(f):
"""
Checks whether the given object `f` is a function or lambda.
:param object f: The object to be checked.
:return: `True` if `f` is a function, `False` otherwise.
:rtype: bool
"""
return type(f) == types.FunctionType or type(f) == types.LambdaType
def chebyshev_roots(n):
"""
Return the roots of *n* Chebyshev polynomials (between [-1, 1]).
:param int n: number of roots
:return: roots
:rtype: torch.tensor
"""
pi = torch.acos(torch.zeros(1)).item() * 2
k = torch.arange(n)
nodes = torch.sort(torch.cos(pi * (k + 0.5) / n))[0]
return nodes