Sorry, John my file was too big and admin rejected post. The candidate file is now 7-zip and should make it through. <snip>
I experimented with FFTs. We need your inputs if we *really*
want to make very high-precision available at this stage.
<snip>
maybe about 30 lines of code.
Nice, had no idea it could be implemented in such a small space!
Ooops, my bad. It was 100 lines. I guess I was in a daze by then. <snip>
So my gut feeling is to hold off for now, and maybe do things properly later (dynamic allocation, better std lib support etc)?
I agree. We should pull the reigns on it for now. We won't get the reliability we need if we try to do something fast. I could go on indefinitely with big-numbs, but we have to get that first version potentially reviewed. I should really get back to my book project soon. But I'm definitely in on any relevant review issues.
I think the existing ones work out quite nicely now thanks, I could use some ideas for integer and maybe rational number examples, but that's a whole other ball game ;-)
I'm not an integer guy. Maybe someone could help us out here. But what springs to my mind is: * Prime factorization * Greatest common denominator (GCD) * Primality testing for Mersenne Primes (has an exceptionally simple algo) * MD5, SHA-1, 2, etc. (but cool std::uint32_t reference apps already exist)<snip>
I resolved the excessive guard digit issue and reduced the guard digits to the necessary amount (and provide rationale in a code comment).
<snip>
Sure, or mail me a patch and I'll run the full tests (or you can - just cd into libs/multiprecision/test and do a "bjam --enable-specfun" and then wait for a long time!) Thanks, John.
OK. I attached my proposed version in /big_number/multiprecision/cpp_dec_float.hpp. The diffs include the removal of some non-needed constants, the trimming of max_digits10 and a minor improvement to the multiplication. Thanks, Chris.