On Tue, 8 Mar 2011 12:13:22 -0800 (PST) Artyom <artyomtnk@yahoo.com> wrote:
- Move Semantics:
It is not clear, and not documented!
That's because it's presently not used. The code is all there for it, but it's disabled because the future of Boost.Move was still up in the air when I wrote it.
To turn it on, define BOOST_XINT_USE_MOVE before including any XInt headers. [...] I haven't tried it, but that code should work the way you expect with the move code enabled.
Yes adding this define makes it work... So it would be good to have it documented :-)
Probably, but it should be a moot point. Boost.Move should make it into the official distribution before XInt, so I'll turn that on permanently.
And this is really nice feature. Seems that integer is capable of handling all possible styles: copy, copy-on-write, move.
Way to go!
:-)
This is the weakest point of this library, the performance of too many algorithms is very low [...]
A lot of that may be due to pass-by-value instead of const references, rather than the algorithms, which I've already corrected for the next release. I'll be testing that soon, maybe today, along with the CoW/move speeds.
Not so sure because I've tried with cow turned on and off and results were almost the same.
Either way, the test results should definitively answer the question, once I can get to them.
AFAIK xint uses "naive" multiplication algorithm and probably some others.
Yes, that's the first algorithm I'll be looking at, once I've finished the more urgent stuff.
[...] I'd suggest to take a look on algorithms that GMP and other use and re-implement them.
I'm leery of looking at any GMP code... it's probably pure paranoia, the GPL can't apply to just *looking* at code, but I'd rather stick to descriptions to ensure that my code doesn't resemble anyone else's and nobody can claim that I've copied from them.
John Bytheway introduced me to a new primality algorithm that I plan to add.
If you are talking about deterministic primality check (ASK)... Don't bother too much, nobody uses them in reality and they have O(scary) complexity. It is something like O(n^6) where n is number of digits...
So don't bother. It is the last thing that users would actually need.
Fortunately, it's also the last and lowest thing on my wish-list. ;-) But I'm curious about the algorithm, and implementing it (someday) is the best way I know of to understand it better. -- Chad Nelson Oak Circle Software, Inc. * * *