Re: [boost] Ann: Statistical distributions / Mathematical Special Functions

From: John Maddock (john_at_[hidden])
Date: 2006-10-08 11:12:02

Janek Kozicki wrote:
> Please note that it's the function shape that is important, not its
> exact vaules at any point. So if you know a 'faster' function that
> has similar shape and has a first derivative I'd like to know about
> it too!

Oh.

I guess if x is small, then you could use a truncated tailor series, and 
either evaluate it as a polynomial, or maybe even just as:

1/(2 - x + x*x)

but other than that, I'd be surprised if there's anything much faster than 
exp()?

John.