I would like to be able to express decimal fractions (i.e. m * 10^{-k} for integers m,k ) with exact precision - as opposed to what we have with binary floating-point values. Essentially there are two options: Floating-point, but decimal (as in this proposal), or fixed point with only the mantissa stored.
So I'm after a library which implements one of these options, or both, reasonably.
Requirements:
- Gratis
- Header-mostly
- LGPL or similar lax FOSS license
- Not abandoned
Desirable:
- Header-only
- As fast as one could expect given the lack of hardware support for this
- Well-documented
- C++11/C++14-oriented
- No significant external dependencies