Files
PINA/tests/test_operators.py
2025-03-19 17:46:34 +01:00

156 lines
5.4 KiB
Python

import torch
import pytest
from pina import LabelTensor
from pina.operators import grad, div, laplacian
def func_vector(x):
return x**2
def func_scalar(x):
x_ = x.extract(['x'])
y_ = x.extract(['y'])
z_ = x.extract(['z'])
return x_**2 + y_**2 + z_**2
data = torch.rand((20, 3))
inp = LabelTensor(data, ['x', 'y', 'z']).requires_grad_(True)
labels = ['a', 'b', 'c']
tensor_v = LabelTensor(func_vector(inp), labels)
tensor_s = LabelTensor(func_scalar(inp).reshape(-1, 1), labels[0])
def test_grad_scalar_output():
grad_tensor_s = grad(tensor_s, inp)
true_val = 2*inp
assert grad_tensor_s.shape == inp.shape
assert grad_tensor_s.labels == [
f'd{tensor_s.labels[0]}d{i}' for i in inp.labels
]
assert torch.allclose(grad_tensor_s, true_val)
grad_tensor_s = grad(tensor_s, inp, d=['x', 'y'])
assert grad_tensor_s.shape == (20, 2)
assert grad_tensor_s.labels == [
f'd{tensor_s.labels[0]}d{i}' for i in ['x', 'y']
]
assert torch.allclose(grad_tensor_s, true_val)
def test_grad_vector_output():
grad_tensor_v = grad(tensor_v, inp)
true_val = torch.cat(
(2*inp.extract(['x']),
torch.zeros_like(inp.extract(['y'])),
torch.zeros_like(inp.extract(['z'])),
torch.zeros_like(inp.extract(['x'])),
2*inp.extract(['y']),
torch.zeros_like(inp.extract(['z'])),
torch.zeros_like(inp.extract(['x'])),
torch.zeros_like(inp.extract(['y'])),
2*inp.extract(['z'])
), dim=1
)
assert grad_tensor_v.shape == (20, 9)
assert grad_tensor_v.labels == [
f'd{j}d{i}' for j in tensor_v.labels for i in inp.labels
]
assert torch.allclose(grad_tensor_v, true_val)
grad_tensor_v = grad(tensor_v, inp, d=['x', 'y'])
true_val = torch.cat(
(2*inp.extract(['x']),
torch.zeros_like(inp.extract(['y'])),
torch.zeros_like(inp.extract(['x'])),
2*inp.extract(['y']),
torch.zeros_like(inp.extract(['x'])),
torch.zeros_like(inp.extract(['y']))
), dim=1
)
assert grad_tensor_v.shape == (inp.shape[0], 6)
assert grad_tensor_v.labels == [
f'd{j}d{i}' for j in tensor_v.labels for i in ['x', 'y']
]
assert torch.allclose(grad_tensor_v, true_val)
def test_div_vector_output():
div_tensor_v = div(tensor_v, inp)
true_val = 2*torch.sum(inp, dim=1).reshape(-1,1)
assert div_tensor_v.shape == (20, 1)
assert div_tensor_v.labels == [f'dadx+dbdy+dcdz']
assert torch.allclose(div_tensor_v, true_val)
div_tensor_v = div(tensor_v, inp, components=['a', 'b'], d=['x', 'y'])
true_val = 2*torch.sum(inp.extract(['x', 'y']), dim=1).reshape(-1,1)
assert div_tensor_v.shape == (inp.shape[0], 1)
assert div_tensor_v.labels == [f'dadx+dbdy']
assert torch.allclose(div_tensor_v, true_val)
def test_laplacian_scalar_output():
laplace_tensor_s = laplacian(tensor_s, inp)
true_val = 6*torch.ones_like(laplace_tensor_s)
assert laplace_tensor_s.shape == tensor_s.shape
assert laplace_tensor_s.labels == [f"dd{tensor_s.labels[0]}"]
assert torch.allclose(laplace_tensor_s, true_val)
laplace_tensor_s = laplacian(tensor_s, inp, components=['a'], d=['x', 'y'])
true_val = 4*torch.ones_like(laplace_tensor_s)
assert laplace_tensor_s.shape == tensor_s.shape
assert laplace_tensor_s.labels == [f"dd{tensor_s.labels[0]}"]
assert torch.allclose(laplace_tensor_s, true_val)
def test_laplacian_vector_output():
laplace_tensor_v = laplacian(tensor_v, inp)
print(laplace_tensor_v.labels)
print(tensor_v.labels)
true_val = 2*torch.ones_like(tensor_v)
assert laplace_tensor_v.shape == tensor_v.shape
assert laplace_tensor_v.labels == [
f'dd{i}' for i in tensor_v.labels
]
assert torch.allclose(laplace_tensor_v, true_val)
laplace_tensor_v = laplacian(tensor_v,
inp,
components=['a', 'b'],
d=['x', 'y'])
true_val = 2*torch.ones_like(tensor_v.extract(['a', 'b']))
assert laplace_tensor_v.shape == tensor_v.extract(['a', 'b']).shape
assert laplace_tensor_v.labels == [
f'dd{i}' for i in ['a', 'b']
]
assert torch.allclose(laplace_tensor_v, true_val)
def test_laplacian_vector_output2():
x = LabelTensor(torch.linspace(0,1,10, requires_grad=True).reshape(-1,1), labels = ['x'])
y = LabelTensor(torch.linspace(3,4,10, requires_grad=True).reshape(-1,1), labels = ['y'])
input_ = LabelTensor(torch.cat((x,y), dim = 1), labels = ['x', 'y'])
# Construct two scalar functions:
# u = x**2 + y**2
# v = x**2 - y**2
u = LabelTensor(input_.extract('x')**2 + input_.extract('y')**2, labels='u')
v = LabelTensor(input_.extract('x')**2 - input_.extract('y')**2, labels='v')
# Define a vector-valued function, whose components are u and v.
f = LabelTensor(torch.cat((u,v), dim = 1), labels = ['u', 'v'])
# Compute the scalar laplacian of both u and v:
# Lap(u) = [4, 4, 4, ..., 4]
# Lap(v) = [0, 0, 0, ..., 0]
lap_u = laplacian(u, input_, components=['u'])
lap_v = laplacian(v, input_, components=['v'])
# Compute the laplacian of f: the two columns should correspond
# to the laplacians of u and v, respectively...
lap_f = laplacian(f, input_, components=['u', 'v'])
assert torch.allclose(lap_f.extract('ddu'), lap_u)
assert torch.allclose(lap_f.extract('ddv'), lap_v)