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## Re: factor inconsistencies/limits?

**From**: |
Jim Meyering |

**Subject**: |
Re: factor inconsistencies/limits? |

**Date**: |
Sun, 27 Jul 2008 09:15:15 +0200 |

"James Youngman" <address@hidden> wrote:
>* On Sat, Jul 26, 2008 at 8:04 PM, James Youngman <address@hidden> wrote:*
>
>*> I have a working GMP-based version (essentially, it's the example*
>*> taken from the GMP docs that you mentioned earlier). For the moment,*
>*> the code always uses GMP if it's available. The GMP version is*
>*> dramatically faster for the pathalogical case mentioned in the docs,*
>*> and about 2x slower for "easy" cases with small integers.*
>
>* It turns out that it needs a little more work, since it does not*
>* currently produce the factors in ascending order. I guess we*
>* probably can't spuriously change that behaviour.*
>
>* Options:*
>* 1. Sort the factors before printing them*
This sounds fine to me.
>* 2. Bluster that we can break the rules for N>2^64, since that never*
>* worked before anyway*
>* 3. Stare hard at the code to find a way to efficiently do the*
>* factorisation and emit the factors in numerical order*
>
>* James.*