On 8/5/2016 12:43 AM, Ilya Yaroshenko wrote:
You are wrong that there are far fewer of those cases. This is naive point of view. A lot of netlib math functions require exact IEEE arithmetic. Tinflex requires it. Python C backend and Mir library require exact IEEE arithmetic. Atmosphere package requires it, Atmosphere is used as reference code for my publication in JMS, Springer. And the most important case: no one top scientific laboratory will use a language without exact IEEE arithmetic by default.
A library has a lot of algorithms in it, a library requiring exact IEEE arithmetic doesn't mean every algorithm in it does. None of the Phobos math library functions require it, and as far as I can tell they are correct out to the last bit.
And besides, all these libraries presumably work, or used to work, on the x87, which does not provide exact IEEE arithmetic for intermediate results without a special setting, and that setting substantially slows it down.
By netlib do you mean the Cephes functions? I've used them, and am not aware of any of them that require reduced precision.
