Tylon 181 Report post Posted June 11, 2006 I have not done math in a while, so I cannot remember how I can achieve this, but this is what I want: I have a function that takes a value between 0 and 1. Here is my function currently: f(x) = (sin(x*PI - PI/2) + 1.0) / 2.0 This *almost* does what I want, since I want: f(x) to be 0 when x is 0 f(x) to be 0.5 when x is 0.5 f(x) to be 1 when x is 1 But I want the curve to go a bit differently. Here is the image of what I have, and what I want: Clicky The red line being the above function which I have, and the blue line being what I would like to have approximatly. Basically, I want the curve to be a bit shallower initially, then steeper suddenly. Can anyone tell me where I can put a variable in my current equation to get what I need? Many thanks! 0 Share this post Link to post Share on other sites
alnite 3438 Report post Posted June 11, 2006 What you need is a sigmoid function. The basic setup is: 1------- 1+e^{-x}Adjust accordingly to your need. 0 Share this post Link to post Share on other sites
Airo 197 Report post Posted June 11, 2006 Your blue curve looks a bit like a shifted Langevin function.http://scienceworld.wolfram.com/physics/LangevinFunction.html 0 Share this post Link to post Share on other sites
Tylon 181 Report post Posted June 11, 2006 Thanks!1/(1+E^(-20*(x-0.5))) seems to do it perfect 0 Share this post Link to post Share on other sites
Tylon 181 Report post Posted June 11, 2006 Quote:Original post by AiroYour blue curve looks a bit like a shifted Langevin function.http://scienceworld.wolfram.com/physics/LangevinFunction.htmlYea, I think that would work to, but I went with sigmoid function; it seems just right. 0 Share this post Link to post Share on other sites