Hi,
First assign any pattern value to the joints.
Then you can use "Interactive database editing".
Export this tables to Excel: "Joint Coordinates" and "Joint pattern assigns".
I guess your model was made using rectangular coordinates, so you should use a function in Excel called "vlookup" in the "Joint pattern assigns" sheet to find rectangular coordinates of each node with a pattern value. Then you can transform rectangular coordinates to polar coordinates using some calculations in Excel. Finally you calculate the desired joint pattern based on the polar coordinates and import the tables to SAP2000.
It is easier than it seems.
I did it a couple of times to apply seismic and wind forces to a liquid containing cilindrcal structure.