bigfloat

[Bill Baxter]

On Thu, Apr 9, 2009 at 2:54 AM, Frank Torte <frankt123978 at gmail.com> wrote:
> Paul D. Anderson Wrote:
>
>> Is there an active project to develop arbitrary-precision floating point numbers for D?
>>
>> I've got a little extra time at the moment and would like to contribute if I can. I've done some work in floating point arithmetic and would be willing to start/complete/add to/test/design/etc. such a project. What I hope NOT to do is to re-implement someone else's perfectly adequate code.
>>
>> If no such project exists I'd like to start one. If there are a bunch of half-finished attempts (I have one of those), let's pool our efforts.
>>
>> I know several contributors here have a strong interest and/or background in numerics. I'd like to hear inputs regarding:
>>
>> a) the merits (or lack) of having an arbitrary-precision floating point type
>>
>> b) the features and functions that should be included.
>>
>> Just to be clear -- I'm talking about a library addition here, not a change in the language.
>>
>> Paul
>>
>>
>
> When you can use a number in D that is more than the number of atoms in the known universe why would you want a bigger number?
>

Size isn't everything.  Arbitrary _precision_ is the goal, not
arbitrary bigness.  Try this experiment:

float i=0;
float j=0;
do {
  j = i;
  i *= 2.0;
} while(j!=i+1.0);
writefln("Loop terminated at j=%s", j);



--bb