Re: [Boost-users] [boost] [review] Multiprecision review scheduled for June 8th - 17th, 2012

Subject: Re: [Boost-users] [boost] [review] Multiprecision review scheduled for June 8th - 17th, 2012
From: John Maddock (boost.regex_at_[hidden])
Date: 2012-06-04 04:29:35

> Why the max_digits10 are not respectively 50,100 and 1?

numeric_limits<>::digits10 are those values.

> The single think in the documentation that could let think the number of
> digits to be greater than the parameter is the *should* word in the 
> sentence
> "The class takes a single template parameter - |Digits10| - which is the
> number of decimal digits precision the type *should* support."
> Could the documentation be more precise?
>
> Is there a way to request for exactly N decimal digits to minimize the
> sizeof?

No, Chris has added a number of guard digits to the implementation of 
cpp_dec_float and there's no way to force it not to use these.  Chris can 
better explain why they're needed.

That's also why max_digits10 > digits10.

John.