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digitalmars.D.announce - Update on Unums

reply Nick B <nick.barbalich gmail.com> writes:
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
Mar 13 2017
next sibling parent rikki cattermole <rikki cattermole.co.nz> writes:
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!
Mar 13 2017
prev sibling next sibling parent reply "H. S. Teoh via Digitalmars-d-announce" writes:
On Mon, Mar 13, 2017 at 08:32:04AM +0000, 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
Mar 13 2017
parent John Colvin <john.loughran.colvin gmail.com> writes:
On Monday, 13 March 2017 at 15:08:56 UTC, H. S. Teoh wrote:

 On Mon, Mar 13, 2017 at 08:32:04AM +0000, Nick B via 
 Digitalmars-d-announce wrote:

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


 [...]

 Link?


urmm...
Mar 13 2017
prev sibling parent reply Andrea Fontana <nospam example.com> writes:
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/
Mar 14 2017
parent reply jmh530 <john.michael.hall gmail.com> writes:
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
Mar 14 2017
parent reply Nick B <nick.barbalich gmail.com> writes:
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
Mar 14 2017
parent reply "H. S. Teoh via Digitalmars-d-announce" writes:
On Tue, Mar 14, 2017 at 06:50:07PM +0000, 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.
Mar 14 2017
parent Nick B <nick.barbalich gmail.com> writes:
On Tuesday, 14 March 2017 at 19:32:57 UTC, H. S. Teoh wrote:

 On Tue, Mar 14, 2017 at 06:50:07PM +0000, 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.
Mar 14 2017