I hope my lispy english is not too annoying. :)
A scene file for the interested:
The pseudocode is:
rotateValue = translateValue/radius * 180/pi # 180/pi in maya expressions can be represented with 180/deg_to_rad(180)
If you want to query the bounding box of an object with expressions use the "xform -q -bb" command and you will get back 6 values. The 3 min values and 3 max values, so just subtract the corresponding ones. You can store it in a float array and subtract [3+i]-[i], where i is in interval [0, 2].
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