Re: Update on Unums

2017-03-14 Thread Nick B via Digitalmars-d-announce

On Tuesday, 14 March 2017 at 19:32:57 UTC, H. S. Teoh wrote:
On Tue, Mar 14, 2017 at 06:50:07PM +, Nick B via 
Digitalmars-d-announce wrote:

On Tuesday, 14 March 2017 at 13:38:09 UTC, jmh530 wrote:
> On Tuesday, 14 March 2017 at 08:21:03 UTC, Andrea Fontana 
> wrote:
> > 
> > It seems public: 
> > http://insidehpc.com/2017/02/john-gustafson-presents-beyond-floating-point-next-generation-computer-arithmetic/
> 
> Also in pdf here 
> http://web.stanford.edu/class/ee380/Abstracts/170201-slides.pdf


Thank you both for posting these links :).

[...]

Indeed.

But while the .pdf mentions Posits and Valids, the following 
slides only discuss Posits.  Where's the discussion on Valids?


In spite of that, though, Posits appear to be a much better 
candidate at replacing IEEE 794 floats than the previous unum 
incarnations. I felt the previous incarnations, while clever 
and workable in theory, posed too many practical challenges to 
implement on silicon.  The current description of Posits seem 
to be much more feasible to put on silicon.


Still, though, I wonder what Gustafson has up his sleeves wrt. 
Valids.


In the Stanford presentation pdf, (note that these change from 
presentation to presentation) on page 12, is the only mention of 
Valids. I thought these were a rename of Sets of Real 
Numbers(SORNS) from his Type 2 Unums, but after reviewing the 
slides again, I'm not sure.  I believe that this needs to be 
vertified with Dr Gustafson, as you correctly point out there are 
no examples of Valids.


But when I review his slides from his New Zealand talk, there is 
an additional slide, where he states that (1) "Posit pairs beat 
intervals at their own games, too: Valid mode." and (2) "Posit 
mode: Round unum after every operation.  Valid mode: rigorous 
answer bounds; NaN answers are sets. "


If anyone wants a copy of these New Zealand slides, please advise 
me of your email address.







Re: Update on Unums

2017-03-14 Thread H. S. Teoh via Digitalmars-d-announce
On Tue, Mar 14, 2017 at 06:50:07PM +, Nick B via Digitalmars-d-announce 
wrote:
> On Tuesday, 14 March 2017 at 13:38:09 UTC, jmh530 wrote:
> > On Tuesday, 14 March 2017 at 08:21:03 UTC, Andrea Fontana wrote:
> > > 
> > > It seems public: 
> > > http://insidehpc.com/2017/02/john-gustafson-presents-beyond-floating-point-next-generation-computer-arithmetic/
> > 
> > Also in pdf here
> > http://web.stanford.edu/class/ee380/Abstracts/170201-slides.pdf
> 
> Thank you both for posting these links :).
[...]

Indeed.

But while the .pdf mentions Posits and Valids, the following slides only
discuss Posits.  Where's the discussion on Valids?

In spite of that, though, Posits appear to be a much better candidate at
replacing IEEE 794 floats than the previous unum incarnations. I felt
the previous incarnations, while clever and workable in theory, posed
too many practical challenges to implement on silicon.  The current
description of Posits seem to be much more feasible to put on silicon.

Still, though, I wonder what Gustafson has up his sleeves wrt. Valids.

But I'm wondering how people would react to switching their numerical
code to projective reals as opposed to the present IEEE 794 system where
you can distinguish between +inf and -inf.  Projective reals have
nice(r) closure properties, but I can see some cases where being unable
to distinguish between +inf and -inf may be problematic.


T

-- 
When solving a problem, take care that you do not become part of the problem.


Re: Update on Unums

2017-03-14 Thread Nick B via Digitalmars-d-announce

On Tuesday, 14 March 2017 at 13:38:09 UTC, jmh530 wrote:

On Tuesday, 14 March 2017 at 08:21:03 UTC, Andrea Fontana wrote:


It seems public: 
http://insidehpc.com/2017/02/john-gustafson-presents-beyond-floating-point-next-generation-computer-arithmetic/


Also in pdf here
http://web.stanford.edu/class/ee380/Abstracts/170201-slides.pdf


Thank you both for posting these links :).

Cheers
Nick


Re: Update on Unums

2017-03-14 Thread jmh530 via Digitalmars-d-announce

On Tuesday, 14 March 2017 at 08:21:03 UTC, Andrea Fontana wrote:


It seems public: 
http://insidehpc.com/2017/02/john-gustafson-presents-beyond-floating-point-next-generation-computer-arithmetic/


Also in pdf here
http://web.stanford.edu/class/ee380/Abstracts/170201-slides.pdf


Re: Update on Unums

2017-03-14 Thread Andrea Fontana via Digitalmars-d-announce

On Monday, 13 March 2017 at 08:32:04 UTC, Nick B wrote:

Hi Everyone

Here is an update on Unums.

John L Gustafson at the Multicore World 2017 Conference, in 
Wellington,  New Zealand, in February 2017, gave another 
presentation to his Unum idea.   He has again reworked the 
basis of his idea again.  He has now called this latest 
version: Type 3 Unums (2017), and introduced new labels of 
Posits and Valids for contrasting Calculation Esthetics.


If I get the approval to post Johns latest presentation, I will 
do so.


cheers
Nick


It seems public: 
http://insidehpc.com/2017/02/john-gustafson-presents-beyond-floating-point-next-generation-computer-arithmetic/


Re: Update on Unums

2017-03-13 Thread John Colvin via Digitalmars-d-announce

On Monday, 13 March 2017 at 15:08:56 UTC, H. S. Teoh wrote:
On Mon, Mar 13, 2017 at 08:32:04AM +, Nick B via 
Digitalmars-d-announce wrote:
If I get the approval to post Johns latest presentation, I 
will do so.

[...]

Link?


urmm...




Re: Update on Unums

2017-03-13 Thread H. S. Teoh via Digitalmars-d-announce
On Mon, Mar 13, 2017 at 08:32:04AM +, Nick B via Digitalmars-d-announce 
wrote:
> Hi Everyone
> 
> Here is an update on Unums.
> 
> John L Gustafson at the Multicore World 2017 Conference, in
> Wellington,  New Zealand, in February 2017, gave another presentation
> to his Unum idea.   He has again reworked the basis of his idea again.
> He has now called this latest version: Type 3 Unums (2017), and
> introduced new labels of Posits and Valids for contrasting Calculation
> Esthetics.
> 
> If I get the approval to post Johns latest presentation, I will do so.
[...]

Link?


T

-- 
MSDOS = MicroSoft's Denial Of Service


Re: Update on Unums

2017-03-13 Thread rikki cattermole via Digitalmars-d-announce

On 13/03/2017 9:32 PM, Nick B wrote:

Hi Everyone

Here is an update on Unums.

John L Gustafson at the Multicore World 2017 Conference, in Wellington,
New Zealand, in February 2017, gave another presentation to his Unum
idea.   He has again reworked the basis of his idea again.  He has now
called this latest version: Type 3 Unums (2017), and introduced new
labels of Posits and Valids for contrasting Calculation Esthetics.

If I get the approval to post Johns latest presentation, I will do so.

cheers
Nick


Nice!


Update on Unums

2017-03-13 Thread Nick B via Digitalmars-d-announce

Hi Everyone

Here is an update on Unums.

John L Gustafson at the Multicore World 2017 Conference, in 
Wellington,  New Zealand, in February 2017, gave another 
presentation to his Unum idea.   He has again reworked the basis 
of his idea again.  He has now called this latest version: Type 3 
Unums (2017), and introduced new labels of Posits and Valids for 
contrasting Calculation Esthetics.


If I get the approval to post Johns latest presentation, I will 
do so.


cheers
Nick