docs: def pld3(pos, line_vertex, line_dir):
      """Calculate the point-line-distance for given point and line."""
      pos = np.atleast_2d(pos)
      line_vertex = np.atleast_1d(line_vertex)
      line_dir = np.atleast_1d(line_dir)
      c = np.cross(line_dir, line_vertex - pos)
      n1 = np.linalg.norm(c, axis=1)
      n2 = np.linalg.norm(line_dir)
      out = n1 / n2
      if out.ndim == 1 and len(out) == 1:
          return out[0]
      return out