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UCS-Based Measures
If you want to use a UCS in creating a measure, you must define the UCS before you define the measure. If you are using a UCS, the references to the WCSX, Y, and Z axes on the dialog boxes are replaced as follows:
Cartesian UCS
Cylindrical UCS
Spherical UCS
X
R
R
Y
T
T
Z
Z
P
Note that displacement measures associated with cylindrical coordinates in the T direction, or spherical coordinates in the T or P directions, are in units of length, not angle.
If you select any of the options on the Measure Definition dialog box that require a coordinate system selection, use the arrow button to select a coordinate system relative to which you define the measure. The default coordinate system is the WCS. You can also select a UCS.
For more information, see About Coordinate Systems.