def get_sketch(self, xs = None):
    """Return a sketch for set xs (all zeros if xs not specified).

    This function takes a list of elements xs, take their hash values, and
    set 1.0 to the corresponding positions. It returns a 2d numpy array
    with width and depth declared in the constructor of CountMinContext.
    Values at unassigned positions remain 0.

    Args:
      xs: a set of name or id in string

    Returns:
      a sketch np.array()
    """
    sketch = np.zeros((self.depth, self.width), dtype=np.float32)
    if xs is not None:
      self.add_set(sketch, xs)
    return sketch
Return a sketch for set xs (all zeros if xs not specified).

    This function takes a list of elements xs, take their hash values, and
    set 1.0 to the corresponding positions. It returns a 2d numpy array
    with width and depth declared in the constructor of CountMinContext.
    Values at unassigned positions remain 0.

    Args:
      xs: a set of name or id in string

    Returns:
      a sketch np.array()
    
language/emql/cm_sketch.py