Bill Baxter wrote:
On Thu, Apr 9, 2009 at 5:46 AM, Andrei Alexandrescu
<seewebsiteforem...@erdani.org> wrote:
Paul D. Anderson wrote:
Walter Bright Wrote:
Paul D. Anderson wrote:
b) the features and functions that should be included.
I'd say NaNs and unordered comparisons. In other words, it should support
the same semantics as float, double and real do.
If you've got the time and interest, adding all the functions in std.math
would be great!
I'm not sure I can sign up for ALL of std.math. I'm sure I'll need
help. I can do roots, powers and transcendental functions, though.
Maybe not very efficiently (power series).
(If very high precision numbers are questionable, how valuable are
high precision sine and cosine??)
Paul
Would be great if we could enlist Don's help. Don? :o)
In only slightly related news, the "new, new" Phobos2 offers custom
floating-point numbers, see
http://erdani.dreamhosters.com/d/web/phobos/std_numeric.html
They aren't infinite precision (which makes their utility orthogonal on
bigfloat's), but they allow fine tweaking of floating point storage. Want to
cram floats in 16 or 24 bits?
Awesome. So we can use it to create the IEEE Halfs that are used by
graphics cards?
It was a big motivator. The example in the dox does exactly that:
alias CustomFloat!(1, 5, 10) HalfFloat;
Care about numbers in [0, 1) at maximum
precision? Give CustomFloat a shot.
By this do you mean you can get a fixed point format? (i'm guessing
so, just by setting exp bits to zero.) If so, then that's very cool
too.
Interesting. I haven't tested exp bits to zero, but that should be
definitely workable. What I meant was still floating point, but with
only negative (or zero) powers. You can do that because you have control
over the bias.
One thing - alias this should greatly simplify using custom floats. It's
not in there yet.
Andrei
