code: def is_single_matrix_pd(mat):
      """Check if 2D square matrix is positive definite."""
      if mat.shape[0] != mat.shape[1]:
          return False
      if mat.dtype in [_torch.complex64, _torch.complex128]:
          is_hermitian = _torch.all(
              _torch.abs(mat - _torch.conj(_torch.transpose(mat, 0, 1)))
              < atol
          )
          if not is_hermitian:
              return False
          eigvals = _torch.linalg.eigvalsh(mat)
          return _torch.min(_torch.real(eigvals)) > 0
      try:
          _torch.linalg.cholesky(mat)
          return True
      except RuntimeError:
          return False
  
file_path: geomstats/geomstats/_backend/pytorch/linalg.py
imports: import numpy
  import scipy
  import torch
  from .._backend_config import np_atol
  from ..numpy import linalg
  from ._dtype import _cast_out_to_input_dtype
label_desc: Use image node_id 7 for calling a global function with example usage: is_single_matrix_pd(mat) and returns: False, unknown, True, False, False