pytorch3d/tests/test_knn.py
Tim Hatch 34bbb3ad32 apply import merging for fbcode/vision/fair (2 of 2)
Summary:
Applies new import merging and sorting from µsort v1.0.

When merging imports, µsort will make a best-effort to move associated
comments to match merged elements, but there are known limitations due to
the diynamic nature of Python and developer tooling. These changes should
not produce any dangerous runtime changes, but may require touch-ups to
satisfy linters and other tooling.

Note that µsort uses case-insensitive, lexicographical sorting, which
results in a different ordering compared to isort. This provides a more
consistent sorting order, matching the case-insensitive order used when
sorting import statements by module name, and ensures that "frog", "FROG",
and "Frog" always sort next to each other.

For details on µsort's sorting and merging semantics, see the user guide:
https://usort.readthedocs.io/en/stable/guide.html#sorting

Reviewed By: bottler

Differential Revision: D35553814

fbshipit-source-id: be49bdb6a4c25264ff8d4db3a601f18736d17be1
2022-04-13 06:51:33 -07:00

263 lines
9.9 KiB
Python

# Copyright (c) Meta Platforms, Inc. and affiliates.
# All rights reserved.
#
# This source code is licensed under the BSD-style license found in the
# LICENSE file in the root directory of this source tree.
import unittest
from itertools import product
import torch
from common_testing import get_random_cuda_device, TestCaseMixin
from pytorch3d.ops.knn import _KNN, knn_gather, knn_points
class TestKNN(TestCaseMixin, unittest.TestCase):
def setUp(self) -> None:
super().setUp()
torch.manual_seed(1)
@staticmethod
def _knn_points_naive(
p1, p2, lengths1, lengths2, K: int, norm: int = 2
) -> torch.Tensor:
"""
Naive PyTorch implementation of K-Nearest Neighbors.
Returns always sorted results
"""
N, P1, D = p1.shape
_N, P2, _D = p2.shape
assert N == _N and D == _D
if lengths1 is None:
lengths1 = torch.full((N,), P1, dtype=torch.int64, device=p1.device)
if lengths2 is None:
lengths2 = torch.full((N,), P2, dtype=torch.int64, device=p1.device)
dists = torch.zeros((N, P1, K), dtype=torch.float32, device=p1.device)
idx = torch.zeros((N, P1, K), dtype=torch.int64, device=p1.device)
for n in range(N):
num1 = lengths1[n].item()
num2 = lengths2[n].item()
pp1 = p1[n, :num1].view(num1, 1, D)
pp2 = p2[n, :num2].view(1, num2, D)
diff = pp1 - pp2
if norm == 2:
diff = (diff * diff).sum(2)
elif norm == 1:
diff = diff.abs().sum(2)
else:
raise ValueError("No support for norm %d" % (norm))
num2 = min(num2, K)
for i in range(num1):
dd = diff[i]
srt_dd, srt_idx = dd.sort()
dists[n, i, :num2] = srt_dd[:num2]
idx[n, i, :num2] = srt_idx[:num2]
return _KNN(dists=dists, idx=idx, knn=None)
def _knn_vs_python_square_helper(self, device, return_sorted):
Ns = [1, 4]
Ds = [3, 5, 8]
P1s = [8, 24]
P2s = [8, 16, 32]
Ks = [1, 3, 10]
norms = [1, 2]
versions = [0, 1, 2, 3]
factors = [Ns, Ds, P1s, P2s, Ks, norms]
for N, D, P1, P2, K, norm in product(*factors):
for version in versions:
if version == 3 and K > 4:
continue
x = torch.randn(N, P1, D, device=device, requires_grad=True)
x_cuda = x.clone().detach()
x_cuda.requires_grad_(True)
y = torch.randn(N, P2, D, device=device, requires_grad=True)
y_cuda = y.clone().detach()
y_cuda.requires_grad_(True)
# forward
out1 = self._knn_points_naive(
x, y, lengths1=None, lengths2=None, K=K, norm=norm
)
out2 = knn_points(
x_cuda,
y_cuda,
K=K,
norm=norm,
version=version,
return_sorted=return_sorted,
)
if K > 1 and not return_sorted:
# check out2 is not sorted
self.assertFalse(torch.allclose(out1[0], out2[0]))
self.assertFalse(torch.allclose(out1[1], out2[1]))
# now sort out2
dists, idx, _ = out2
if P2 < K:
dists[..., P2:] = float("inf")
dists, sort_idx = dists.sort(dim=2)
dists[..., P2:] = 0
else:
dists, sort_idx = dists.sort(dim=2)
idx = idx.gather(2, sort_idx)
out2 = _KNN(dists, idx, None)
self.assertClose(out1[0], out2[0])
self.assertTrue(torch.all(out1[1] == out2[1]))
# backward
grad_dist = torch.ones((N, P1, K), dtype=torch.float32, device=device)
loss1 = (out1.dists * grad_dist).sum()
loss1.backward()
loss2 = (out2.dists * grad_dist).sum()
loss2.backward()
self.assertClose(x_cuda.grad, x.grad, atol=5e-6)
self.assertClose(y_cuda.grad, y.grad, atol=5e-6)
def test_knn_vs_python_square_cpu(self):
device = torch.device("cpu")
self._knn_vs_python_square_helper(device, return_sorted=True)
def test_knn_vs_python_square_cuda(self):
device = get_random_cuda_device()
# Check both cases where the output is sorted and unsorted
self._knn_vs_python_square_helper(device, return_sorted=True)
self._knn_vs_python_square_helper(device, return_sorted=False)
def _knn_vs_python_ragged_helper(self, device):
Ns = [1, 4]
Ds = [3, 5, 8]
P1s = [8, 24]
P2s = [8, 16, 32]
Ks = [1, 3, 10]
norms = [1, 2]
factors = [Ns, Ds, P1s, P2s, Ks, norms]
for N, D, P1, P2, K, norm in product(*factors):
x = torch.rand((N, P1, D), device=device, requires_grad=True)
y = torch.rand((N, P2, D), device=device, requires_grad=True)
lengths1 = torch.randint(low=1, high=P1, size=(N,), device=device)
lengths2 = torch.randint(low=1, high=P2, size=(N,), device=device)
x_csrc = x.clone().detach()
x_csrc.requires_grad_(True)
y_csrc = y.clone().detach()
y_csrc.requires_grad_(True)
# forward
out1 = self._knn_points_naive(
x, y, lengths1=lengths1, lengths2=lengths2, K=K, norm=norm
)
out2 = knn_points(
x_csrc, y_csrc, lengths1=lengths1, lengths2=lengths2, K=K, norm=norm
)
self.assertClose(out1[0], out2[0])
self.assertTrue(torch.all(out1[1] == out2[1]))
# backward
grad_dist = torch.ones((N, P1, K), dtype=torch.float32, device=device)
loss1 = (out1.dists * grad_dist).sum()
loss1.backward()
loss2 = (out2.dists * grad_dist).sum()
loss2.backward()
self.assertClose(x_csrc.grad, x.grad, atol=5e-6)
self.assertClose(y_csrc.grad, y.grad, atol=5e-6)
def test_knn_vs_python_ragged_cpu(self):
device = torch.device("cpu")
self._knn_vs_python_ragged_helper(device)
def test_knn_vs_python_ragged_cuda(self):
device = get_random_cuda_device()
self._knn_vs_python_ragged_helper(device)
def test_knn_gather(self):
device = get_random_cuda_device()
N, P1, P2, K, D = 4, 16, 12, 8, 3
x = torch.rand((N, P1, D), device=device)
y = torch.rand((N, P2, D), device=device)
lengths1 = torch.randint(low=1, high=P1, size=(N,), device=device)
lengths2 = torch.randint(low=1, high=P2, size=(N,), device=device)
out = knn_points(x, y, lengths1=lengths1, lengths2=lengths2, K=K)
y_nn = knn_gather(y, out.idx, lengths2)
for n in range(N):
for p1 in range(P1):
for k in range(K):
if k < lengths2[n]:
self.assertClose(y_nn[n, p1, k], y[n, out.idx[n, p1, k]])
else:
self.assertTrue(torch.all(y_nn[n, p1, k] == 0.0))
def test_knn_check_version(self):
try:
from pytorch3d._C import knn_check_version
except ImportError:
# knn_check_version will only be defined if we compiled with CUDA support
return
for D in range(-10, 10):
for K in range(-10, 20):
v0 = True
v1 = 1 <= D <= 32
v2 = 1 <= D <= 8 and 1 <= K <= 32
v3 = 1 <= D <= 8 and 1 <= K <= 4
all_expected = [v0, v1, v2, v3]
for version in range(-10, 10):
actual = knn_check_version(version, D, K)
expected = False
if 0 <= version < len(all_expected):
expected = all_expected[version]
self.assertEqual(actual, expected)
def test_invalid_norm(self):
device = get_random_cuda_device()
N, P1, P2, K, D = 4, 16, 12, 8, 3
x = torch.rand((N, P1, D), device=device)
y = torch.rand((N, P2, D), device=device)
with self.assertRaisesRegex(ValueError, "Support for 1 or 2 norm."):
knn_points(x, y, K=K, norm=3)
with self.assertRaisesRegex(ValueError, "Support for 1 or 2 norm."):
knn_points(x, y, K=K, norm=0)
@staticmethod
def knn_square(N: int, P1: int, P2: int, D: int, K: int, device: str):
device = torch.device(device)
pts1 = torch.randn(N, P1, D, device=device, requires_grad=True)
pts2 = torch.randn(N, P2, D, device=device, requires_grad=True)
grad_dists = torch.randn(N, P1, K, device=device)
torch.cuda.synchronize()
def output():
out = knn_points(pts1, pts2, K=K)
loss = (out.dists * grad_dists).sum()
loss.backward()
torch.cuda.synchronize()
return output
@staticmethod
def knn_ragged(N: int, P1: int, P2: int, D: int, K: int, device: str):
device = torch.device(device)
pts1 = torch.rand((N, P1, D), device=device, requires_grad=True)
pts2 = torch.rand((N, P2, D), device=device, requires_grad=True)
lengths1 = torch.randint(low=1, high=P1, size=(N,), device=device)
lengths2 = torch.randint(low=1, high=P2, size=(N,), device=device)
grad_dists = torch.randn(N, P1, K, device=device)
torch.cuda.synchronize()
def output():
out = knn_points(pts1, pts2, lengths1=lengths1, lengths2=lengths2, K=K)
loss = (out.dists * grad_dists).sum()
loss.backward()
torch.cuda.synchronize()
return output