The user has changed the units in the units manager, but it does not affect the units of "Center of Mass". Also changing the units in the Measure dialog preferences, will not affect the units of "Center of Mass'.
Solution
Points are always millimeters ( or part units ) because the point expression does not have any units. We show millimeters because if you save the measurement, the created expression will always be in millimeters (part units). So the units of "Center of Mass" will always be in Part Units, irrespective of the units set in the "Units Manager" or the Measure Preferences dialog.
Hardware/Software Configuration
Platform: INTEL OS: windows OS Version: 1064 Product: NX Application: DESIGN Version: V1953 Function: INFO_ANALYSIS
