def moments_of_masked_time_series(time_series_tensor, broadcast_mask):
  """Compute mean and variance, accounting for a mask.

  Args:
    time_series_tensor: float `Tensor` time series of shape
      `concat([batch_shape, [num_timesteps]])`.
    broadcast_mask: bool `Tensor` of the same shape as `time_series`.
  Returns:
    mean: float `Tensor` of shape `batch_shape`.
    variance: float `Tensor` of shape `batch_shape`.
  """
  num_unmasked_entries = tf.cast(
      tf.reduce_sum(input_tensor=tf.cast(~broadcast_mask, tf.int32), axis=-1),
      time_series_tensor.dtype)

  # Manually compute mean and variance, excluding masked entries.
  mean = (tf.reduce_sum(input_tensor=tf.where(
      broadcast_mask,
      tf.zeros_like(time_series_tensor),
      time_series_tensor), axis=-1) / num_unmasked_entries)
  variance = (tf.reduce_sum(input_tensor=tf.where(
      broadcast_mask,
      tf.zeros_like(time_series_tensor),
      (time_series_tensor - mean[..., tf.newaxis]) ** 2), axis=-1)
              / num_unmasked_entries)
  return mean, variance
def moments_of_masked_time_series ( time_series_tensor , broadcast_mask ) : num_unmasked_entries = tf . cast ( tf . reduce_sum ( input_tensor = tf . cast ( ~ broadcast_mask , tf . int32 ) , axis = - 1 ) , time_series_tensor . dtype ) mean = ( tf . reduce_sum ( input_tensor = tf . where ( broadcast_mask , tf . zeros_like ( time_series_tensor ) , time_series_tensor ) , axis = - 1 ) / num_unmasked_entries ) variance = ( tf . reduce_sum ( input_tensor = tf . where ( broadcast_mask , tf . zeros_like ( time_series_tensor ) , ( time_series_tensor - mean [ ... , tf . newaxis ] ) ** 2 ) , axis = - 1 ) / num_unmasked_entries ) return mean , variance
Compute mean and variance, accounting for a mask.

  Args:
    time_series_tensor: float `Tensor` time series of shape
      `concat([batch_shape, [num_timesteps]])`.
    broadcast_mask: bool `Tensor` of the same shape as `time_series`.
  Returns:
    mean: float `Tensor` of shape `batch_shape`.
    variance: float `Tensor` of shape `batch_shape`.