This is pretty rare, and it's also fairly tough to represent points in spaces of fractional dimension. I'll bet the sorts of complications necessary to do so would immediately exclude it from consideration in the design of a standard library, but nevertheless would be interesting to hear about. Can you comment further on this? Even without fractals, there are cases where weird dimensions come up (I ran across this in my old MHDL (microwave) days). Square root volts is the example that was constantly thrown in my face. It doesn't really mess up the model that much; you just have to use rational dimensions rather than integer dimensions. Everything else works out. I have *not* come across a case where real dimensions are necessary, so equality still works. Dave Barton <*> dlb@averstar.com )0( http://www.averstar.com/~dlb