docstr: Test degenerate case when input matrices are diagonal or near-diagonal
docstr_tok: ["Test","degenerate","case","when","input","matrices","are","diagonal","or","near-diagonal"]
code: def _test_degenerate_inputs(self, device):
      """
      Test degenerate case when input matrices are diagonal or near-diagonal
      """
  
      # Purely diagonal case
      test_input = self.create_diag_sym3x3(device, self.TEST_BATCH_SIZE)
  
      self._test_is_not_nan_or_inf(test_input)
      self._test_is_eigen(test_input)
      self._test_eigenvectors_are_orthonormal(test_input)
  
      # Almost-diagonal case
      test_input = self.create_diag_sym3x3(
          device, self.TEST_BATCH_SIZE, noise=1e-4
      )
  
      self._test_is_not_nan_or_inf(test_input)
      self._test_is_eigen(test_input)
      self._test_eigenvectors_are_orthonormal(test_input)
  
imports: import unittest
  import torch
  from pytorch3d.common.workaround import symeig3x3
  from pytorch3d.transforms.rotation_conversions import random_rotations
  from .common_testing import get_random_cuda_device, TestCaseMixin
label_desc: Use image node_id 15 for calling the TestSymEig3x3 obj's underlying member method code with example usage: obj._test_degenerate_inputs(device) without return types