class_docstr: Horizontal line annotation at the given position.
class_docstr_tok: ["Horizontal","line","annotation","at","the","given","position","."]
code: def __init__(self, y, **params):
      if isinstance(y, np.ndarray) and y.size == 1:
          y = np.atleast_1d(y)[0]
      super().__init__(y, y=y, **params)
  
imports: from numbers import Number
  import numpy
  import param
  from ..core import Dimension, Element, Element2D
  from ..core.data import Dataset
  from ..core.util import datetime_types
label_desc: Use image node_id 1 to create a new HLine object from inherited base classes: Annotation with example: obj = HLine(y)