Re: What´s the algorithm that compresses a 20 digit big int, into 8 bytes ?

On Apr 8, 10:57 am, Sampo Syreeni <de..._at_iki.fi> wrote:

> Unless my trusty old TI-86 is losing precision in embarrassing places,
> I should also add that 64 bits doesn't quite suffice for 20 decimal
> digits; it has 18 per cent or so of the total range, so you'd have to
> go with 19 digits or three extra bits.
> --
> Sampo

Indeed. So a few hypothesis:

1. Another algorithm is being used.
2. 72 bits are being used, and vendors are claiming 64 for marketing purposes, the justification is that 67 is closer to 64 than 72, notwithstanding the fact that 67 bits require full 72 bits on machines with a byte size of 8.

There may of course be other hypothesis, thanks for bringing up this very interesting fact. Received on Fri Apr 09 2010 - 16:36:41 CEST