Karim Belabas on Mon, 22 Oct 2012 22:31:44 +0200


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Re: exp is faster the second time round 

* Dirk Laurie [2012-10-22 22:19]:
> With \p 1000000, it takes about a minute to compute exp
> on my laptop.  Immediate afterwards, it takes about 30 seconds.
> 
> Obviously some constants are being memoized.  Which
> constants are these?

log(2)     

Since exp(x - k log(2)) = x / 2^k, argument reduction allows us to
assume that |x| <= log(2)/2

Cheers,

    K.B.
--
Karim Belabas, IMB (UMR 5251)  Tel: (+33) (0)5 40 00 26 17
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