code: def entr(x, out=None, where=None, **kwargs):
      r"""
      Elementwise function for computing entropy.
  
      .. math:: \text{entr}(x) = \begin{cases} - x \log(x) & x > 0  \\ 0 & x = 0 \\ -\infty & \text{otherwise} \end{cases}
  
      Parameters
      ----------
      x : Tensor
          Input tensor.
  
      Returns
      -------
      res : Tensor
          The value of the elementwise entropy function at the given points `x`.
  
      See Also
      --------
      kl_div, rel_entr
  
      Notes
      -----
      This function is concave.
      """
      op = TensorEntr(**kwargs)
      return op(x, out=out, where=where)
  
file_path: mars/mars/tensor/special/info_theory.py
imports: import scipy.special
  from ..arithmetic.utils import arithmetic_operand
  from ..utils import infer_dtype, implement_scipy
  from .core import TensorSpecialUnaryOp, TensorSpecialBinOp, _register_special_op
label_desc: Use image node_id 1 for calling a global function with example usage: entr(x, out, where) and returns: op