pryrt Thank you very much indeed. Thanks to your leads; I've ended up finding the Logistic function, which with its tunable slope and rotational symmetry is exactly the function I was looking for, despite that I didn't know it existed :)

I'm still getting to grips with how the tunable parameter(s) affect the curve; and I need to deal with the fact that at steep slopes, the y values stay hard at the bottom and top of the range for too long -- I think I'll need to fiddle with x-range to ensure that I start and finish at the beginning and end of the curves rather than well before and after; but I think I can handle that.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority". The enemy of (IT) success is complexity.
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^2: A data selection problem(in3D). by BrowserUk
in thread A data selection problem(in3D). by BrowserUk

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