code: def entropy(density):
      """Compute the entropy of a matrix/density object.
  
      This computes -Tr(density*ln(density)) using the eigenvalue decomposition
      of density, which is given as either a Density instance or a matrix
      (numpy.ndarray, sympy.Matrix or scipy.sparse).
  
      Parameters
      ==========
  
      density : density matrix of type Density, SymPy matrix,
      scipy.sparse or numpy.ndarray
  
      Examples
      ========
  
      >>> from sympy.physics.quantum.density import Density, entropy
      >>> from sympy.physics.quantum.spin import JzKet
      >>> from sympy import S
      >>> up = JzKet(S(1)/2,S(1)/2)
      >>> down = JzKet(S(1)/2,-S(1)/2)
      >>> d = Density((up,S(1)/2),(down,S(1)/2))
      >>> entropy(d)
      log(2)/2
  
      """
      if isinstance(density, Density):
          density = represent(density)  # represent in Matrix
  
      if isinstance(density, scipy_sparse_matrix):
          density = to_numpy(density)
  
      if isinstance(density, Matrix):
          eigvals = density.eigenvals().keys()
          return expand(-sum(e * log(e) for e in eigvals))
      elif isinstance(density, numpy_ndarray):
          import numpy as np
  
          eigvals = np.linalg.eigvals(density)
          return -np.sum(eigvals * np.log(eigvals))
      else:
          raise ValueError(
              "numpy.ndarray, scipy.sparse or SymPy matrix expected"
          )
  
imports: from itertools import product
  from sympy.core.add import Add
  from sympy.core.containers import Tuple
  from sympy.core.function import expand
  from sympy.core.mul import Mul
  from sympy.core.singleton import S
  from sympy.functions.elementary.exponential import log
  from sympy.matrices.dense import MutableDenseMatrix
  from sympy.printing.pretty.stringpict import prettyForm
  from sympy.physics.quantum.dagger import Dagger
  from sympy.physics.quantum.operator import HermitianOperator
  from sympy.physics.quantum.represent import represent
  from sympy.physics.quantum.matrixutils import numpy_ndarray, scipy_sparse_matrix, to_numpy
  from sympy.physics.quantum.tensorproduct import TensorProduct, tensor_product_simp
  from sympy.physics.quantum.trace import Tr
label_desc: Use image node_id 1 for calling a global function with example usage: entropy(density) and returns: expand, unknown