Re: [Algorithms] Formula for Damping f times

[Fabian G. <f.g...@49...>]

> exp() is one of the simplest and most direct math function to
> implement. It should be approximately the cost of, say, five or
> sequential six multiply-adds (and that includes range reduction and
> reconstruction). Do not fear exp().
> 
> pow(), however, is a different story.

But since the log is only done on k (which is, presumably, a constant), 
you can just store log(k) directly and do exp(log(k)*t) (with some small 
loss in accuracy that's unlikely to be a problem).

Also, if you have them, base-2 log and exp are usually slightly faster 
and have less potential for extra rounding errors on IEEE FP machines.

-Fabian Giesen