See also gaussian curve/bell curve/s-curve... Although of course that was a straight spline curve in the first pic. Splines will give you what you want, but maybe not in the most simple way.
Chris On 19 Mar 2010, at 19:52, Dan Winckler wrote: > Thanks, Tom and Jon! I remembered Grapher earlier today and it was a big > help, even though polynomial curves are not among its examples (sure beats my > old TI-82). Now to tweak the numbers until they give me the shape I need. > Additional help still welcome if offered. :) > > best, > dan > > > > <Screen shot 2010-03-19 at 3.49.57 PM.png> > > > On Mar 19, 2010, at 3:40 PM, Jon Pugh wrote: > >> At 3:14 PM -0400 3/19/10, Dan Winckler wrote: >>> What do you call a curve like the one in the attached image? Rather, >>> what's the mathematical term for the equation that produces such a double >>> curve. I am trying to scale an incoming float number (0.0 1.0) so that it >>> changes more quickly in the middle of the range (~0.2 - 0.8) than at the >>> top and bottom (~ 0.0 - 0.2, 0.8 - 1.0). Right now I've got exponential >>> scaling, which works for the bottom of the range but not the top. >> >> This is a curve produced by a polynomial equation. I recommend opening the >> application Grapher, which came with your Mac, and entering this equation: x >> = y^3+y^2+y >> >> This will give you a curve approximating the one you've drawn. Then you can >> play with adding numbers before the various terms (i.e. 3y^3, etc) to change >> the shape of the curve. >> >> Good luck. >> >> Jon >> _______________________________________________ >> Do not post admin requests to the list. They will be ignored. >> Quartzcomposer-dev mailing list ([email protected]) >> Help/Unsubscribe/Update your Subscription: >> http://lists.apple.com/mailman/options/quartzcomposer-dev/dan%40danwinckler.com >> >> This email sent to [email protected] > > _______________________________________________ > Do not post admin requests to the list. They will be ignored. > Quartzcomposer-dev mailing list ([email protected]) > Help/Unsubscribe/Update your Subscription: > http://lists.apple.com/mailman/options/quartzcomposer-dev/psonice%40gmail.com > > This email sent to [email protected] _______________________________________________ Do not post admin requests to the list. They will be ignored. Quartzcomposer-dev mailing list ([email protected]) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/quartzcomposer-dev/archive%40mail-archive.com This email sent to [email protected]
