why map frame isn't continuous
I try to understand the different coordinate frame in ROS. I see a explication of map frame like follow, "The coordinate frame called map is a world fixed frame, with its Z-axis pointing upwards. The pose of a mobile platform, relative to the map frame, should not significantly drift over time. The map frame is not continuous, meaning the pose of a mobile platform in the map frame can change in discrete jumps at any time. In a typical setup, a localization component constantly re-computes the robot pose in the map frame based on sensor observations, therefore eliminating drift, but causing discrete jumps when new sensor information arrives. The map frame is useful as a long-term global reference, but discrete jumps make it a poor reference frame for local sensing and acting." So my question is why the map frame is not continuous? Isn't all the coordinate frame continuous? thx
