code: def isinf(x, out=None, where=None, **kwargs):
      """
      Test element-wise for positive or negative infinity.
  
      Returns a boolean array of the same shape as `x`, True where ``x ==
      +/-inf``, otherwise False.
  
      Parameters
      ----------
      x : array_like
          Input values
      out : Tensor, None, or tuple of Tensor and None, optional
          A location into which the result is stored. If provided, it must have
          a shape that the inputs broadcast to. If not provided or `None`,
          a freshly-allocated tensor is returned. A tuple (possible only as a
          keyword argument) must have length equal to the number of outputs.
      where : array_like, optional
          Values of True indicate to calculate the ufunc at that position, values
          of False indicate to leave the value in the output alone.
      **kwargs
  
      Returns
      -------
      y : bool (scalar) or boolean Tensor
          For scalar input, the result is a new boolean with value True if
          the input is positive or negative infinity; otherwise the value is
          False.
  
          For tensor input, the result is a boolean tensor with the same shape
          as the input and the values are True where the corresponding
          element of the input is positive or negative infinity; elsewhere
          the values are False.  If a second argument was supplied the result
          is stored there.  If the type of that array is a numeric type the
          result is represented as zeros and ones, if the type is boolean
          then as False and True, respectively.  The return value `y` is then
          a reference to that tensor.
  
      See Also
      --------
      isneginf, isposinf, isnan, isfinite
  
      Notes
      -----
      Mars uses the IEEE Standard for Binary Floating-Point for Arithmetic
      (IEEE 754).
  
      Errors result if the second argument is supplied when the first
      argument is a scalar, or if the first and second arguments have
      different shapes.
  
      Examples
      --------
      >>> import mars.tensor as mt
  
      >>> mt.isinf(mt.inf).execute()
      True
      >>> mt.isinf(mt.nan).execute()
      False
      >>> mt.isinf(mt.NINF).execute()
      True
      >>> mt.isinf([mt.inf, -mt.inf, 1.0, mt.nan]).execute()
      array([ True,  True, False, False])
  
      >>> x = mt.array([-mt.inf, 0., mt.inf])
      >>> y = mt.array([2, 2, 2])
      >>> mt.isinf(x, y).execute()
      array([1, 0, 1])
      >>> y.execute()
      array([1, 0, 1])
      """
      op = TensorIsInf(**kwargs)
      return op(x, out=out, where=where)
  
file_path: mars/mars/tensor/arithmetic/isinf.py
imports: import numpy
  from ...None import opcodes
  from ..utils import inject_dtype
  from .core import TensorUnaryOp
  from .utils import arithmetic_operand
label_desc: Use image node_id 1 for calling a global function with example usage: isinf(x, out, where) and returns: op