class_docstr: Gaussian measurement interface.
  
  :param mean: mean of measurement distribution.
  :param cov: covariance of measurement distribution.
  :param time: continuous time of measurement. If this is not
        provided, `frame_num` must be.
  :param frame_num: discrete time of measurement. If this is not
        provided, `time` must be.
class_docstr_tok: ["Gaussian","measurement","interface",".",":","param","mean",":","mean","of","measurement","distribution",".",":","param","cov",":","covariance","of","measurement","distribution",".",":","param","time",":","continuous","time","of","measurement",".","If","this","is","not","provided",",","`","frame_num","`","must","be",".",":","param","frame_num",":","discrete","time","of","measurement",".","If","this","is","not","provided",",","`","time","`","must","be","."]
docstr: Discrete time of measurement.
docstr_tok: ["Discrete","time","of","measurement","."]
code: def frame_num(self):
      """
      Discrete time of measurement.
      """
      return self._frame_num
  
imports: from abc import ABCMeta, abstractmethod
  import torch
  from pyro.distributions.util import eye_like
label_desc: Use image node_id 6 for calling the Measurement obj's underlying member method code with example usage: obj.frame_num() and returns: self