[Haskell-cafe] faster factorial function via FFI?

Bryan O'Sullivan bos at serpentine.com
Mon Apr 23 19:36:14 EDT 2007


Dan Drake wrote:

> This is combinatorics, so I can't just say "oh, this is small" and cross
> it off like physicists do. :)

Binary splitting is much faster than the naive approach, but still easy 
to understand.  That's fac1 in the attached file.

I ran out of time to write an efficient implementation using swing 
numbers, but my slow, crummy version is present as fac2, just as a data 
point.

	<b
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