I haven't seen any and this apparently been discussed in detail on compuserv
several years ago. My suggestion, although kludgy, was to use a dummy
worksheet, fill the union with constants, clear the intersection, then use
specialcells with the union to return the inverse.

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Regards,
Tom Ogilvy

"keepITcool" wrote in message
...

Hi..

this one's for the experts/mathematicians amongst us..
(Harlan, you reading this ? :)


does anyone have some routines to invert a (multiarea) selection?
or ...along the same line of thought ..

to get the the inverse of intersect.. (generally that would give a
"LEFT" bucket and a "RIGHT" bucket.

It MUST be fast.. thus a simple loop will never suffice.
unions above 400 areas get dreadfully slow..

My theory (and bit of practice too:)

First get the 'outside range' sized from topleft to bottom right cell
of the multiarea.. that's done. (be carefull of unordered areas.)

Then create an array of same dimensions... and mark off the selected
cells. much faster then checking intersect during a 'normal' loop.

But then..? I need an efficient routine to create a a new range object
from that array... Since you want to avoid just dumping every TRUE in
the array in a union and let excel figure it out..

SO probably I need a 'mazing' algorithm but there I'm stuck for the
moment..and I'm pretty sure there must be some nice routines out there!


anyone?..

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keepITcool
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