On Thursday, 25 February 2016 at 10:36:08 UTC, Robbert van Dalen wrote:
> On Wednesday, 24 February 2016 at 21:43:59 UTC, Nick B wrote:
>> On Wednesday, 24 February 2016 at 20:11:39 UTC, Robbert van Dalen wrote:

>
> Nick,
>
> I've just asked Dr. Gustafson to create a group on his behalf and he was fine with it:
> https://groups.google.com/forum/#!forum/unum-computing
>
>  It would be nice if you'd subscribe to it:

Robbert,

I will subscribe, as you suggested.  I see that the new user group has been getting page views already. Thats quick.

Nick

On Tuesday, 23 February 2016 at 21:47:10 UTC, H. S. Teoh wrote:
> On Tue, Feb 23, 2016 at 09:20:23PM +0000, Nick B via Digitalmars-d wrote:
>
> I do want to clarify, though, that I think at this point implementing unum in the D compiler is almost certainly premature. What I had in mind was more of a unum library that early adopters can use to get a feel for how things would work.
>  If the unum system turns out to have garner enough support that it starts getting hardware support, then it should be relatively easy to transition it into a built-in type.  I don't see this happening for at least another 5-10, though.  It took at least as long (probably longer) for hardware manufacturers to adopt the IEEE standard, and right now unums aren't even standardized yet.
>
>
> T

just a quick update re Unum 2.0

I hope to be able to present a link to the finalised paper on Unums within 24 to 48 hours.

Also here, below, is an quick update, on the software development on Unums from Prof Gustafson.

"Work is progressing on a reference C implementation on two fronts, and I am presently trying to unite the two. One is the coding by Isaac Yonemoto, which is being funded by my Singapore employer (A*STAR)... which is like having a team of about eight programmers, right there. He's an ultra-fast programmer and a crack mathematician as well, so he finds amazing shortcuts and insights that I don't notice. Isaac tends to code in Julia first, and C second. When he does C, he almost does assembler; he carefully studies what x86 instructions are available and squeezes every cycle.

The other is a small team at UC Santa Cruz with one applied math grad student doing most of the coding and a couple of faculty advisors (plus me dialing in now and then), and just about has plus-minus-times-divide working, the last I heard. This is part of an Open Source initiative, so you can bet that this will be documented and released into the wild the way open source software should be. That one is going for C directly.

There may be other efforts. Some MIT folks also created a Julia version of type 2 unums, and it may be almost as fast as C. There may be others."

On Tuesday, 9 August 2016 at 09:45:58 UTC, Nick B wrote:
> On Tuesday, 23 February 2016 at 21:47:10 UTC, H. S. Teoh wrote:
>> On Tue, Feb 23, 2016 at 09:20:23PM +0000, Nick B via Digitalmars-d wrote:
?
> I hope to be able to present a link to the finalised paper on Unums within 24 to 48 hours.
>

Here is the link to the paper as promised.

http://www.johngustafson.net/pubs/RadicalApproach.pdf

Please note that Figure 8 on page 9 has errors.  Three of the four-bit unums on this figure is wrong, as you have duplicates of 0110, 0100, 0010.

For the correct diagram please see page 20 on  http://www.johngustafson.net/presentations/Unums2.0.pdf

Nick

On Wednesday, 10 August 2016 at 08:36:41 UTC, Nick B wrote:
> On Tuesday, 9 August 2016 at 09:45:58 UTC, Nick B wrote:
> http://www.johngustafson.net/pubs/RadicalApproach.pdf
>
> Please note that Figure 8 on page 9 has errors.

Please note these errors have now been corrected, and the paper  is distributed under the terms of the Creative Commons Attribution-Non Commercial 3.0 License which permits non-commercial use, reproduction and distribution of the work without further permission provided the original work is properly cited."

Does anyone have any feedback on this paper ?

Does anyone feel that Unums should be part of D ?

Nick

On Sun, Aug 14, 2016 at 09:08:31PM +0000, Nick B via Digitalmars-d wrote:
> On Wednesday, 10 August 2016 at 08:36:41 UTC, Nick B wrote:
> > On Tuesday, 9 August 2016 at 09:45:58 UTC, Nick B wrote: http://www.johngustafson.net/pubs/RadicalApproach.pdf
> > 
> > Please note that Figure 8 on page 9 has errors.
> 
> Please note these errors have now been corrected, and the paper  is distributed under the terms of the Creative Commons Attribution-Non Commercial 3.0 License which permits non-commercial use, reproduction and distribution of the work without further permission provided the original work is properly cited."
> 
> Does anyone have any feedback on this paper ?
> 
> Does anyone feel that Unums should be part of D ?
[...]

I'm personally quite interested in a D implementation of unums as described in the paper. However, I'm unsure if it should be part of the official D distribution, since this is still very early and the unum system hasn't been "proven in the field" just yet.  While I certainly hope this research would eventually revolutionize numerical applications, it would take a long time before it would catch on, and until then, I think it's better to have unums available as a library rather than introducing it into the language itself. Having it available via dub or something like that would probably be a very good idea.

Thanks to operator overloading and alias this, we can probably do a pretty good job implementing unums as a library so that people can try it out.  It would also be an interesting exercise to implement unums in D and take advantage of CTFE in ways that may give us very nice implementational possibilities.


T

-- 
A program should be written to model the concepts of the task it performs rather than the physical world or a process because this maximizes the potential for it to be applied to tasks that are conceptually similar and, more important, to tasks that have not yet been conceived. -- Michael B. Allen

On Wednesday, 10 August 2016 at 08:36:41 UTC, Nick B wrote:
> For the correct diagram please see page 20 on  http://www.johngustafson.net/presentations/Unums2.0.pdf
>

This still mention:
> 1-clock binary ops with no exception cases

Sure it can, but you won't like the frequency.

On Monday, 15 August 2016 at 00:42:16 UTC, H. S. Teoh wrote:
> On Sun, Aug 14, 2016 at 09:08:31PM +0000, Nick B via Digitalmars-d wrote:

> While I certainly hope this research would eventually revolutionize numerical applications, it would take a long time before it would catch on, and until then, I think it's better to have unums available as a library rather than introducing it into the language itself. Having it available via dub or something like that would probably be a very good idea.

I totally agree.

> Thanks to operator overloading and alias this, we can probably do a pretty good job implementing unums as a library so that people can try it out.

It may be easier to link to the reference C implementation first.

I note that I haven't seen any feedback from Walter or Andrei. I can only assume that neither are interested in this subject.

Nick

On Wednesday, 17 August 2016 at 03:44:48 UTC, Nick B wrote:
> On Monday, 15 August 2016 at 00:42:16 UTC, H. S. Teoh wrote:
>> On Sun, Aug 14, 2016 at 09:08:31PM +0000, Nick B via Digitalmars-d wrote:
>
>> While I certainly hope this research would eventually revolutionize numerical applications, it would take a long time before it would catch on, and until then, I think it's better to have unums available as a library rather than introducing it into the language itself. Having it available via dub or something like that would probably be a very good idea.
>
> I totally agree.
>
>> Thanks to operator overloading and alias this, we can probably do a pretty good job implementing unums as a library so that people can try it out.
>
> It may be easier to link to the reference C implementation first.
>
> I note that I haven't seen any feedback from Walter or Andrei. I can only assume that neither are interested in this subject.
>
> Nick

FWIW I skimmed through the paper and it looks very interesting and I would definitely experiment with it if it's available in D(ub).

If you want Andrei or Walter's opinion on whether they could in principle imagine Unum as part of Phobos or even the language, you should ping them directly via mail.

On Wed, Aug 17, 2016 at 03:44:48AM +0000, Nick B via Digitalmars-d wrote:
> On Monday, 15 August 2016 at 00:42:16 UTC, H. S. Teoh wrote:
[...]
> > Thanks to operator overloading and alias this, we can probably do a pretty good job implementing unums as a library so that people can try it out.
> 
> It may be easier to link to the reference C implementation first.

Easier, certainly. But I think D may offer some advantages over a purely C implementation. It's worth exploring, at any rate.


> I note that I haven't seen any feedback from Walter or Andrei. I can only assume that neither are interested in this subject.
[...]

More likely, they are too busy with other things to respond.


T

-- 
The diminished 7th chord is the most flexible and fear-instilling chord. Use it often, use it unsparingly, to subdue your listeners into submission!

On Wednesday, 17 August 2016 at 11:34:15 UTC, Seb wrote:

>
> If you want Andrei or Walter's opinion on whether they could in principle imagine Unum as part of Phobos or even the language, you should ping them directly via mail.

Agreed.