August 5, 2015

Post puzzles for others to solve here.

Re: August 5, 2015

Postby eleven » Sun Aug 09, 2015 1:22 pm

Don,

after 10 yeras AIC i notice following:

- There is no definition, how simple constructs like a hidden pair link is written
- The chief AIC fundamentalist still cannot formulate a correct AIC
- There are pages over pages filled with struggles between AIC writers, what is correct
- In fact AIC writers are freehand writers themselves
- The only thing, they have in common is, that "equal" means "or"

My conclusion is clear: AIC is a monstrosity, which swamped the sudoku community, and which we cannot get rid anymore.
DonM wrote:So, eleven, my challenge to you was not to error-check my solution (though I do appreciate it) nor was it to in any way use my solution. It was to come up with your own entire solution of Gurth's puzzle using your freehand method and let us see how easy it is to follow (for newcomers or allcomers) vs. Eureka-AIC notation.

Since i already showed you, that i have no problem to translate your solution into my notation, why should i do?
If you want a real challenge, come to a Greek island in the first 2 weeks of September, and let us enjoy solving puzzles on paper. But be warned, my wife, who is not able to speak AIC, might win.
Finally, my guess is that you were able to quickly error-check my solution because the notation was so clear.

You must be joking. I could, although the notation was wrong (it must be HP, not aHP).
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Re: August 5, 2015

Postby denis_berthier » Sun Aug 09, 2015 3:54 pm

eleven wrote:after 10 yeras AIC i notice following:
- There is no definition, how simple constructs like a hidden pair link is written
- The chief AIC fundamentalist still cannot formulate a correct AIC
- There are pages over pages filled with struggles between AIC writers, what is correct
- In fact AIC writers are freehand writers themselves
- The only thing, they have in common is, that "equal" means "or"
My conclusion is clear: AIC is a monstrosity, which swamped the sudoku community, and which we cannot get rid anymore.

As you may expect, I fully agree on all lines.
To 'The only thing, they have in common is, that "equal" means "or"', I would only add: which is in itself the chief monstrosity for anyone with the slightest background in logic, mathematics or computer science - or even with the slightest commonsense.

DonM wrote: ... The first statement is a dismissive statement implying that anyone using Eureka notation is biased as if Eureka notation is of minor value and there are realistic alternatives, ...

You claim not only that AIC is the "standard" notation (which you have the right to believe, if your faith is so large), but also that there is no alternative one, which is a huge absurdity, as you have been aware of the nrc notation for years.

The nrc notation is the Sudoku version of a general <Variable, value> notation meaningful for any finite CSP; it fully displays the symmetry of row, column and numbers. Its general <Variable, value> form has been concretely applied to all sorts of puzzles.

The main points are (see my book for more details):
. every pattern must be prefixed by its name (bivalue-chain = basic AIC, whip, naked-quad, ...) so that everyone knows what is being written before checking details
. "—" means link, i.e. direct contradiction between two candidates (it doesn't seem to be a monstrosity !!!!)
. in a chain pattern, X{a b} means that CSP-Variable X can only have values a or b modulo previous elements depending on the type of chain defined by the prefix;
. whenever a complex sub-pattern is used as a right-linking element, it is defined in a similar way, possibly on a different line, e.g.:
... X{a B} ...
where B = Hidden-Pair-in-a-row: r3{n2 n4}{c5 c7}


BTW, the solution of the original puzzle requires only chains no more complex than pure whips and no longer than 4!!!

Hidden Text: Show
Code: Select all
***  SudoRules 20.0.s based on CSP-Rules 2.0.s, config = W  ***
singles ==> r9c2 = 8, r4c2 = 2, r8c2 = 6, r6c4 = 3, r5c4 = 6, r4c4 = 4, r4c6 = 1, r5c5 = 2, r8c6 = 5, r8c8 = 1, r8c7 = 8, r8c4 = 9, r2c4 = 5, r3c4 = 8, r8c1 = 2, r9c4 = 7, r9c6 = 3, r7c6 = 6, r3c6 = 4, r7c5 = 8, r9c5 = 1, r5c3 = 7, r2c5 = 9
whip[1]: c9n3{r3 .} ==> r3c8 ≠ 3, r2c7 ≠ 3, r1c8 ≠ 3, r1c7 ≠ 3
whip[1]: c3n1{r3 .} ==> r3c1 ≠ 1, r2c1 ≠ 1

biv-chain[3]: r3c1{n5 n6} - r2n6{c1 c7} - b3n7{r2c7 r3c8} ==> r3c8 ≠ 5
whip[3]: c3n8{r1 r4} - r4c9{n8 n5} - b3n5{r1c9 .} ==> r1c3 ≠ 5
biv-chain[4]: r3c1{n5 n6} - r2c1{n6 n4} - r2c3{n4 n1} - r3n1{c3 c9} ==> r3c9 ≠ 5
whip[1]: r3n5{c3 .} ==> r1c1 ≠ 5
biv-chain[4]: r3c5{n6 n3} - b1n3{r3c2 r2c2} - r2n7{c2 c7} - r2n6{c7 c1} ==> r3c1 ≠ 6
naked-single ==> r3c1 = 5
biv-chain[4]: c8n3{r7 r5} - r5n9{c8 c1} - r9c1{n9 n4} - r9c8{n4 n5} ==> r7c8 ≠ 5
biv-chain[4]: r9n5{c8 c3} - c3n9{r9 r4} - r4n8{c3 c9} - c9n5{r4 r1} ==> r1c8 ≠ 5
biv-chain[4]: r6c1{n1 n8} - b1n8{r1c1 r1c3} - b1n2{r1c3 r3c3} - r3n1{c3 c9} ==> r6c9 ≠ 1
whip[1]: c9n1{r3 .} ==> r2c7 ≠ 1
biv-chain[4]: c1n6{r2 r1} - c1n8{r1 r6} - r6n1{c1 c7} - c7n7{r6 r2} ==> r2c7 ≠ 6
hidden-single-in-a-row ==> r2c1 = 6
biv-chain[4]: r6c7{n7 n1} - r6c1{n1 n8} - r1c1{n8 n4} - r2n4{c3 c7} ==> r2c7 ≠ 7
stte

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Re: August 5, 2015

Postby David P Bird » Sun Aug 09, 2015 4:12 pm

eleven wrote:The chief AIC fundamentalist still cannot formulate a correct AIC

Eleven, the points you make are detracting from your argument but force a reply.

You seem to be confusing typing skills with logical analysis skills. However my typos were easily spotted because of the formal chain structure which wouldn't be so easy with your informal one.

As I've said in the past when you described the way you solve without pencil marks, you are clearly an adept solver with a memory that has a far greater capacity for holding key relationships than mine. Instead I use GEM to mark my spreadsheet grid and find my eliminations that way. I then notate them using the Eureka conventions for the benefit of less experienced players. This translation is annoying because I use the '-' and '=' symbols in a different way, but I got voted down when the basic Eureka approach was thrashed out on the Eureka forum.

Since then it's been possible to define Booleans for further patterns as they have been identified, but on this forum, because there is no will to try to reach a consensus, everyone wants to designate them in a different way which is the cause for the endless debate you mention – not the alternating Booleans. I wonder why there is no debate about your system – might it be that you're the only one using it?

I'm a fundamentalist because find that if I allow myself to use branched and unidirectional chains the vast majority of puzzles become too trivial. It's been by refusing to use these methods I've kept my interest in Sudoku going (unlike many others) as I try to find new extensions to the deductions I can make and so deter the onset of Alzheimer's. However in this discussion these disciplines aren't an issue; I haven't mentioned branching at all and bi-directional chains only as an aside.

I consider that the role of a notation is to present the logic used as clearly as possible so that someone who is unused to a particular situation is guided through it. Every gap in your stream presents an opportunity for that person misread it and make the wrong inference. Goodness knows how many discussions discontinuous nice loops have caused because of the missing internal links in cells.

Your notations are meant for a different class of reader altogether. They are expected to work out how you make the connections you do. You've seen how I translated a chain segment into words in my walk though<here>. I don't believe that's possible for your inference stream of Aug 5th using the arguments in the order you gave them.

PS Denis, I see you're chipping in now but have a completely different agenda. Three questions for you
1) Did you find your solution manually? We are discussing notations suitable for human players.
2) One of Eleven's points is that the Eureka system scares players because it's too complicated to learn. What about yours?
3) Does Eleven's inference stream satisfy your mathematical criteria?
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Re: August 5, 2015

Postby denis_berthier » Sun Aug 09, 2015 4:31 pm

David P Bird wrote:Denis, I see you're chipping in now but have a completely different agenda. Three questions for you
1) Did you find your solution manually? We are discussing notations suitable for human players.
2) One of Eleven's points is that the Eureka system scares players because it's too complicated to learn. What about yours?
3) Does Eleven's inference stream satisfy your mathematical criteria?


Probably you could tell me what my agenda is.
1) Whether a notation is suitable for a human player depends on its intrinsic properties; it should be usable by both human solver and software.
2) Mine is very simple
3) I'ven't read it

4) as usual, you evade the real points
Last edited by denis_berthier on Sun Aug 09, 2015 4:49 pm, edited 1 time in total.
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Re: August 5, 2015

Postby ronk » Sun Aug 09, 2015 4:42 pm

David P Bird wrote:You've seen how I translated a chain segment into words in my walk though<here>.

Since it should have been obvious to you that I didn't know that "#1" meant "at least one", that walk through was insulting. For you to now be pointing to this walk through compounds the insult.
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Re: August 5, 2015

Postby David P Bird » Sun Aug 09, 2015 5:38 pm

denis_berthier wrote:
David P Bird wrote:Denis, I see you're chipping in now but have a completely different agenda. Three questions for you
1) Did you find your solution manually? We are discussing notations suitable for human players.
2) One of Eleven's points is that the Eureka system scares players because it's too complicated to learn. What about yours?
3) Does Eleven's inference stream satisfy your mathematical criteria?


Probably you could tell me what my agenda is.
1) Whether a notation is suitable for a human player depends on its intrinsic properties; it should be usable by both human solver and software.
2) Mine is very simple
3) I'ven't read it

4) as usual, you evade the real points

I have my suspicion but no more on what your agenda might be. However, I believe that you would be equally critical of Eleven's inference stream notation had you read it and your contribution would have been different.

As for 4) Eleven was responding to Don M who has taken the discussion in his own direction. I therefore leave them to resolve that diversion for themselves. However Eleven made a reference to me which stirred me to respond in my defence.
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Re: August 5, 2015

Postby David P Bird » Sun Aug 09, 2015 5:54 pm

ronk wrote:
David P Bird wrote:You've seen how I translated a chain segment into words in my walk though<here>.

Since it should have been obvious to you that I didn't know that "#1" meant "at least one", that walk through was insulting. For you to now be pointing to this walk through compounds the insult.

Ronk it was far from obvious to me where your problem was so I gave a long winded response on the basis that if you didn't need all that detail it might be of benefit to others. I thought that that you would understand that as it's far from the first time I've gone into more detail than is really needed with other readers in mind.

The moral of the episode is that we draw conclusions at out own peril. But let me assure you no insult was intended either originally or by my link to that post.
Last edited by David P Bird on Sun Aug 09, 2015 9:03 pm, edited 1 time in total.
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Re: August 5, 2015

Postby eleven » Sun Aug 09, 2015 8:59 pm

David, i did not mean you, when i spoke of the chief AIC fundamentalist, you seem to be too tolerant for that.
I am aware, that your personal AIC rules are well-considered, though i don't know where they are defined.
I am also aware, that the AIC definitions 2006 made sense, before all the other techniques and specials were discovered. And i understand, that it was a good alternative to the "try any candidate and see, if it causes a contradiction" method.
But it was missed to reform the definitions according to the new discoveries, and install a site for reference. In my eyes the main reason for this lack was the always fighting Eureka community, where no agreement could be reached.

I am no fan of Denis' notation and chain definitions, but at least they are well defined.

I am not aware, that anything would be missing in my example notations.
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Re: August 5, 2015

Postby DonM » Sun Aug 09, 2015 10:49 pm

denis_berthier wrote:
DonM wrote: ... The first statement is a dismissive statement implying that anyone using Eureka notation is biased as if Eureka notation is of minor value and there are realistic alternatives, ...

You claim not only that AIC is the "standard" notation (which you have the right to believe, if your faith is so large), but also that there is no alternative one, which is a huge absurdity, as you have been aware of the nrc notation for years.

The nrc notation is the Sudoku version of a general <Variable, value> notation meaningful for any finite CSP; it fully displays the symmetry of row, column and numbers. Its general <Variable, value> form has been concretely applied to all sorts of puzzles.

The main points are (see my book for more details):...

The operative words here are 'realistic' and 'standard'. Your nrc notation is not by any measure a standard for manual solving and never has been any more than other alternative methods such as Bill's OR Chains (from the old Eureka forum) or eleven's freehand method. (On that score, it is not surprising that you and eleven have formed a mutual admiration society on this subject.) Nor has nrc notation been demonstrated to be a realistic alternative to Eureka notation for manual solving (please see below).

I bought your book (right after it was published) based on its promotion as a new manual solving method. Never have I felt more misled by a sudoku book since it became very apparent that it was more appropriate for some niche of academia and/or a new approach to computer solving.

To me, absurdity is your promotion of your notation as a manual method when virtually every solution you have posted on this forum has been computer output. The most recent example is below where at least 3 solvers posted one-step solutions while your nrc-based computer solution was by any comparison long and obscure. Do you really think that a manual solver is going to look at that and say, 'Hey, what have I been missing!'

http://forum.enjoysudoku.com/july-25-2015-t32580.html

BTW, the solution of the original puzzle requires only chains no more complex than pure whips and no longer than 4!!!

[hidden][code]*** SudoRules 20.0.s based on CSP-Rules 2.0.s, config = W ***
singles ==> r9c2 = 8, r4c2 = 2, r8c2 = 6, r6c4 = 3, r5c4 = 6, r4c4 = 4, r4c6 = 1, r5c5 = 2, r8c6 = 5, r8c8 = 1, r8c7 = 8, r8c4 = 9, r2c4 = 5, r3c4 = 8, r8c1 = 2, r9c4 = 7, r9c6 = 3, r7c6 = 6, r3c6 = 4, r7c5 = 8, r9c5 = 1, r5c3 = 7, r2c5 = 9
whip[1]: c9n3{r3 .} ==> r3c8 ≠ 3, r2c7 ≠ 3, r1c8 ≠ 3, r1c7 ≠ 3
whip[1]: c3n1{r3 .} ==> r3c1 ≠ 1, r2c1 ≠ 1

biv-chain[3]: r3c1{n5 n6} - r2n6{c1 c7} - b3n7{r2c7 r3c8} ==> r3c8 ≠ 5
whip[3]: c3n8{r1 r4} - r4c9{n8 n5} - b3n5{r1c9 .} ==> r1c3 ≠ 5
biv-chain[4]: r3c1{n5 n6} - r2c1{n6 n4} - r2c3{n4 n1} - r3n1{c3 c9} ==> r3c9 ≠ 5
whip[1]: r3n5{c3 .} ==> r1c1 ≠ 5
biv-chain[4]: r3c5{n6 n3} - b1n3{r3c2 r2c2} - r2n7{c2 c7} - r2n6{c7 c1} ==> r3c1 ≠ 6
naked-single ==> r3c1 = 5
biv-chain[4]: c8n3{r7 r5} - r5n9{c8 c1} - r9c1{n9 n4} - r9c8{n4 n5} ==> r7c8 ≠ 5
biv-chain[4]: r9n5{c8 c3} - c3n9{r9 r4} - r4n8{c3 c9} - c9n5{r4 r1} ==> r1c8 ≠ 5
biv-chain[4]: r6c1{n1 n8} - b1n8{r1c1 r1c3} - b1n2{r1c3 r3c3} - r3n1{c3 c9} ==> r6c9 ≠ 1
whip[1]: c9n1{r3 .} ==> r2c7 ≠ 1
biv-chain[4]: c1n6{r2 r1} - c1n8{r1 r6} - r6n1{c1 c7} - c7n7{r6 r2} ==> r2c7 ≠ 6
hidden-single-in-a-row ==> r2c1 = 6
biv-chain[4]: r6c7{n7 n1} - r6c1{n1 n8} - r1c1{n8 n4} - r2n4{c3 c7} ==> r2c7 ≠ 7
stte


How sad, but telling, that we are at a point where someone will post a computer-derived solution and make a point out of how much simpler it is than a manual solution. It is almost in the same category as someone who posts a computer-derived solution with the implication that it is derived from their own manual efforts (which, parenthetically, continues to occur far too often). I'm sure your computer spit out the above in seconds. My solution took several hours, but it came from my own (albeit limited) brain. I don't profess to be a brainiac solver, but every single solution ever posted of mine is my own, proof of which is the mistake in my solution that eleven found.

Finally, a form of communication such as notation becomes a standard over time. Eureka/AIC notation was not a standard in 2006, but it became the de facto standard when by far the majority of manual solvers dropped Nice Loop notation and when virtually all (or most) of the advances in solving from 2007 on were transmitted using Eureka notation. Even SteveK converted to using Eureka notation on the main forums even though he had been using his (essentially AIC) forbidding chains and different numbered/lettered grid on his Australia forum blog.

EDIT:
Perhaps David Is too diplomatic to mention it, but I have no problem doing so:
He asked you specifically '1) Did you find your solution manually? We are discussing notations suitable for human players.' Your answer was ,' Whether a notation is suitable for a human player depends on its intrinsic properties; it should be usable by both human solver and software.'
That you evaded the question so flagrantly speaks volumes.
Last edited by DonM on Mon Aug 10, 2015 12:15 am, edited 1 time in total.
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Re: August 5, 2015

Postby DonM » Mon Aug 10, 2015 12:05 am

eleven wrote:Don,

after 10 yeras AIC i notice following:

- There is no definition, how simple constructs like a hidden pair link is written
- The chief AIC fundamentalist still cannot formulate a correct AIC
- There are pages over pages filled with struggles between AIC writers, what is correct
- In fact AIC writers are freehand writers themselves
- The only thing, they have in common is, that "equal" means "or"

Before I answer, I want it clearly understood that I respect you as a talented and gifted solver. My issues with you have almost always been with the way you evade subjects like this with misleading or irrelevant examples or the way you will divert a discussion by posing unrelated questions or challenges.

Case in point is your above statements which are irrelevant and trivial when it comes to the proven value of Eureka notation over the years in communicating solutions of even the most complexity such as those that were posted by SteveK and ttt. No notation is perfect and the process of adapting Eureka notation to newly-discovered methods was at times trying, but it did work. Proof being that when these new methods were posted using Eureka notation, while there were disagreements over the best way to notate those methods, virtually no reasonably experienced solver was crying out, 'I don't understand, I don't understand!'.

DonM wrote:So, eleven, my challenge to you was not to error-check my solution (though I do appreciate it) nor was it to in any way use my solution. It was to come up with your own entire solution of Gurth's puzzle using your freehand method and let us see how easy it is to follow (for newcomers or allcomers) vs. Eureka-AIC notation.

eleven wrote:Since i already showed you, that i have no problem to translate your solution into my notation, why should i do?

That is a prime example of your evading the subject. There has never been a question of your ability to translate my solution to yours. The question is (and you know this full well since I've explained it twice): Since you claim that the Eureka notation is so badly flawed, can you show that your notation would be superior to Eureka notation in clarity for higher difficulty puzzles requiring several lines?

I have never seen you solve a long, complex puzzle using your notation and that includes all those years when advanced solving was occurring on the Eureka forum and sometimes here. Unless I have missed it, it has always been for one-steppers or just where there are 2 or 3 lines of code. In other words, how can you fairly compare these two notations where just a few lines of code are required?

DonM wrote:Finally, my guess is that you were able to quickly error-check my solution because the notation was so clear.

eleven wrote:You must be joking. I could, although the notation was wrong (it must be HP, not aHP).


So my notation wasn't clear because I used aHP rather than HP? Really? Are you that desperate? Again, another example of an irrelevant response.

(Actually, I do prefer HP over aHP -said so to Ronk years ago- because IMO, as you say, it is the correct form, but for some reason, I didn't use it here. Who cares!)
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Re: August 5, 2015

Postby denis_berthier » Mon Aug 10, 2015 7:12 am

DonM wrote:Your nrc notation is not by any measure a standard for manual solving and never has been any more than other alternative methods such as Bill's OR Chains (from the old Eureka forum) or eleven's freehand method. (On that score, it is not surprising that you and eleven have formed a mutual admiration society on this subject.) Nor has nrc notation been demonstrated to be a realistic alternative to Eureka notation for manual solving.
To me, absurdity is your promotion of your notation as a manual method when virtually every solution you have posted on this forum has been computer output.

nrc notation hasn't become a standard on the late Eureka or Sudoku Player's forums, mainly because of their being dominated by a clan of Eureka extremists who wouldn't hear of anything else.
As for the rest, you are just repeating ad nauseam your old confusing claims. But a notation should be directed to the reader. It should be non-ambiguous and compact (but not overly compact). Whether examples of it are generated by hand or computer is totally irrelevant.


As for the general idea of "alternating inference", I defy you to find a better than nrc notation for it.
I'll let anyone judge for himself which of the following two options is clearer.

My nrc notation, with my general chain pattern:
{x1 Y1} — {x2 Y2} — {x3 Y3} — ... ==> not Z, where the xi are candidates and the Yi are candidates in the simplest cases but may be full patterns (to be defined within the {} or in separate lines) in more complex cases
— means linked, in direct contradiction, logical nand, i.e. it corresponds to your "weak links", a place where nothing really happens;
{x X} corresponds to your "strong links"; the { } notation provides space for where interesting things happen.
Concrete examples from my previous solution:
whip[3]: c3n8{r1 r4} - r4c9{n8 n5} - b3n5{r1c9 .} ==> r1c3 ≠ 5
biv-chain[4]: r3c1{n5 n6} - r2c1{n6 n4} - r2c3{n4 n1} - r3n1{c3 c9} ==> r3c9 ≠ 5

Or examples taken from the above "solutions":
9r9c3 =UR= 3r7c8 - (3=4&6)r147c7 - (4|6=137)r2c279 - (1=9)r279c3
[(9r9c3=3r7c8)ur:45r79c38-(3=456)r147c7-(46=137)r2c279-(1=9)r279c3]-45r9c3
(9=45)r79c3 -UR- (45=3)r79c8 - (3=456)r147c7 - (46#1=17#1)r2c7 - (137=4)r2c239 - (45=9)r79c3 => r9c3 = 9
(9=45)r79c3 -UR- (45=3)r79c8 - (3=456)r147c7 - (46#1)r2c7 = (6,4)r2c1,r2c3 - (45=9)r79c3 => r9c3 = 9
(45)r27c3 = (3)r7c7[AMSLS133445567:2n2379,7n3,147n7] - (3)r7c8 = (9)r9c3[AUR45:r79c38] => r9c3 <> 4
(9=45)r79c3 -UR- (45=3)r79c8 - (3=456)r147c7 - (46#1=17#1)r2c2 = (137=4)r2c239 - (45=9)r79c3 => r9c3 = 9


DonM wrote:I bought your book (right after it was published) based on its promotion as a new manual solving method. Never have I felt more misled by a sudoku book since it became very apparent that it was more appropriate for some niche of academia and/or a new approach to computer solving.

My book (I suppose you are speaking of HLS1, 2007) was never promoted as a manual solving method but as a complete theoretically based resolution model, based on pure logic. It also introduced new kinds of chains, at the pure logic level. Once more, whether such chains are found by humans or computers is irrelevant to their definitions.
Since the beginning, you have been allergic to oriented chains. That's your right and I respect it. But I can't accept that you consider that they are not for manual solvers. Many solutions proposed in this section of the forum use oriented chains (or even nets), pretending not to be aware of previous work and thus re-inventing the wheel.

You also constantly ignore the difference between AND branching (propagating the consequences of one step) and OR branching (bifurcating because there are several possible conclusions). Some of my chains have AND branching (seen in the t-candidates) but no OR-branching.
Indeed, there is some limited form of OR-branching in g-whips, but it is totally wrapped in the notion of a g-candidate.


DonM wrote:The most recent example is below where at least 3 solvers posted one-step solutions while your nrc-based computer solution was by any comparison long and obscure.

My solution was based on several very easy steps that anyone can understand without much effort. Most of them are bivalue chains (i.e. basic AICs). Only one is oriented, the only whip[3].
The pretendedly one-step solutions are totally artificial ones that no normal player would ever consider. They are so complicated that they generated three full pages of discussion and misunderstandings, part of which is due to under-specified AIC notation and part of which is due to uncertain logic.
The fact is, this whole section of the forum has become a monstrosity. Notice, I consider anyone is free to look for such artificially complicated solutions if that's what they like. But please don't try to make us believe that this is any kind of standard that a normal player should take as an example.

DonM wrote:Perhaps David Is too diplomatic to mention it, but I have no problem doing so:
He asked you specifically '1) Did you find your solution manually? We are discussing notations suitable for human players.' Your answer was ,' Whether a notation is suitable for a human player depends on its intrinsic properties; it should be usable by both human solver and software.'
That you evaded the question so flagrantly speaks volumes.

One more absurd claim. My resolution path started with "*** SudoRules 20.0.s based on CSP-Rules 2.0.s, config = W ***"
Isn't it explicit enough? Should I write it in red bold size 60 capital letters for you?
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Re: August 5, 2015

Postby ronk » Mon Aug 10, 2015 4:50 pm

DonM wrote:
eleven wrote:You must be joking. I could, although the notation was wrong (it must be HP, not aHP).

So my notation wasn't clear because I used aHP rather than HP? Really? Are you that desperate? Again, another example of an irrelevant response.

(Actually, I do prefer HP over aHP -said so to Ronk years ago- because IMO, as you say, it is the correct form, but for some reason, I didn't use it here. Who cares!)

Since you imply my conclusion would be "aHP" in this case, I decided to check.

here you wrote:(7)r5c2=aHP(79-3)r48c2=(3)r6c3 => -7r6c3

The aHP (79)c2 is comprised of two candidate values in three cells r458c2. Strictly speaking, your usage of aHP is for two cells r48c2, which is actually an HP after (7)r5c2 is removed from consideration.

BTW I strongly prefer r6c3<>7 or r6c3 ≠ 7 over -7r6c3 for exclusions.
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Re: August 5, 2015

Postby DonM » Mon Aug 10, 2015 6:23 pm

denis_berthier wrote:nrc notation hasn't become a standard on the late Eureka or Sudoku Player's forums, mainly because of their being dominated by a clan of Eureka extremists who wouldn't hear of anything else.As for the rest, you are just repeating ad nauseam your old confusing claims. But a notation should be directed to the reader. It should be non-ambiguous and compact (but not overly compact). Whether examples of it are generated by hand or computer is totally irrelevant.


Facts: The late Eureka forum and the original Sudoku Players forums were the source of virtually all the major advances in manual sudoku solving. The original standard notation for a brief period was Nice Loop notation, but was supplanted by Eureka/AIC notation circa 2007.

Facts: Eureka notation has been proven to be effective for use by manual solvers based on the fact that the top solvers (already mentioned) found it accessible. Some of the most (in retrospect) astounding advances such as Kraken/AAIC networks were made accessible to manual solvers by the use of Eureka notation even though it was said (I believe by Mike Barker) that it was unlikely they could reasonably be found manually by most solvers. The most complex solutions for the most difficult (ER=9 and above) puzzles were posted using Eureka notation by ttt and they were quite understandable.

Facts: A notation that originates mainly out of the efforts of manual solvers will likely be more accessible to manual solvers than one that is so associated with computer output. Your notation never caught on anywhere of note and not because of some paranoia-based domination by 'a clan of Eureka extremists.'

denis_berthier wrote:...Or examples taken from the above "solutions":
9r9c3 =UR= 3r7c8 - (3=4&6)r147c7 - (4|6=137)r2c279 - (1=9)r279c3
[(9r9c3=3r7c8)ur:45r79c38-(3=456)r147c7-(46=137)r2c279-(1=9)r279c3]-45r9c3
(9=45)r79c3 -UR- (45=3)r79c8 - (3=456)r147c7 - (46#1=17#1)r2c7 - (137=4)r2c239 - (45=9)r79c3 => r9c3 = 9
(9=45)r79c3 -UR- (45=3)r79c8 - (3=456)r147c7 - (46#1)r2c7 = (6,4)r2c1,r2c3 - (45=9)r79c3 => r9c3 = 9
(45)r27c3 = (3)r7c7[AMSLS133445567:2n2379,7n3,147n7] - (3)r7c8 = (9)r9c3[AUR45:r79c38] => r9c3 <> 4
(9=45)r79c3 -UR- (45=3)r79c8 - (3=456)r147c7 - (46#1=17#1)r2c2 = (137=4)r2c239 - (45=9)r79c3 => r9c3 = 9

The pretendedly one-step solutions are totally artificial ones that no normal player would ever consider. They are so complicated that they generated three full pages of discussion and misunderstandings, part of which is due to under-specified AIC notation and part of which is due to uncertain logic.
The fact is, this whole section of the forum has become a monstrosity. Notice, I consider anyone is free to look for such artificially complicated solutions if that's what they like. But please don't try to make us believe that this is any kind of standard that a normal player should take as an example.


Unfortunately, there is some truth to the above, but that has nothing to do with the overall already-proven value and utility of the Eureka notation. What is happening now is due to at least 3 circumstances:

1. The one-stepper challenge for virtually all puzzles posted which has resulted in contortions in logic to achieve the one-stepper and then the ensuing twisting and turning of the Eureka notation to try to explain it. That is not the fault of a notation that worked perfectly fine to explain most solutions before the history of this more recent forum.

2. The lack of helpful guidance, oversight and credibility by several very talented people in the past who had both advanced manual and Boolean/mathematical logic skills. (David Bird is/was one of those, but is a lone voice in the wilderness. Though not a manual solver, Ronk has also played a helpful role in the standardizing of the notation over the years.) Their presence was one of the reasons why the Eureka notation was used so successfully from 2007 to circa 2012.

3. The insult on injury that is occurring where you have solvers who do not have the background of experiencing the use of the Eureka notation during the years when the basic standards had been largely settled on, but are now, inexplicably, introducing their own shorthand changes that combined with attempts at complex one-steppers makes for some of the more unfortunate, to use your words, 'artificially complicated solutions' .

Again, none of the above is the fault of the notation.
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Re: August 5, 2015

Postby DonM » Mon Aug 10, 2015 6:56 pm

ronk wrote:
DonM wrote:
eleven wrote:You must be joking. I could, although the notation was wrong (it must be HP, not aHP).

So my notation wasn't clear because I used aHP rather than HP? Really? Are you that desperate? Again, another example of an irrelevant response.

(Actually, I do prefer HP over aHP -said so to Ronk years ago- because IMO, as you say, it is the correct form, but for some reason, I didn't use it here. Who cares!)

Since you imply my conclusion would be "aHP" in this case, I decided to check.

here you wrote:(7)r5c2=aHP(79-3)r48c2=(3)r6c3 => -7r6c3

The aHP (79)c2 is comprised of two candidate values in three cells r458c2. Strictly speaking, your usage of aHP is for two cells r48c2, which is actually an HP after (7)r5c2 is removed from consideration.

BTW I strongly prefer r6c3<>7 or r6c3 ≠ 7 over -7r6c3 for exclusions.


My apologies, it was not my intention to infer what your preference was. I agree that HP is correct and that has been my opinion in the past. I also agree with your statement about exclusions. I've tried to adapt, in a very limited way, to some of the apparent notation changes in this forum. Perhaps that is a mistake.

EDIT:
For no other reason, but interest sake, I just remembered a main reason why I started switching to -7r6c3 over r6c3<>7. It was because in some instances when I would transfer my solutions from MS Word or Wordpad to the forum, the <> would cause unexpected results. Memory fades as to whether that was here, elsewhere or both.
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Re: August 5, 2015

Postby eleven » Mon Aug 10, 2015 7:21 pm

DonM wrote:Before I answer, I want it clearly understood that I respect you as a talented and gifted solver.

Thanks.
DonM wrote:There has never been a question of your ability to translate my solution to yours.

Not ? I thought so.
The question is (and you know this full well since I've explained it twice): Since you claim that the Eureka notation is so badly flawed, can you show that your notation would be superior to Eureka notation in clarity for higher difficulty puzzles requiring several lines?

I did not say badly flawed, but badly defined, and unnecessarily hard to read for newcomers. I know, that "my" notation (which is just an example, how it could be done alternatively), is not better for you. But it could be read by newcomers without learning any notation.
I have never seen you solve a long, complex puzzle using your notation and that includes all those years when advanced solving was occurring on the Eureka forum and sometimes here. Unless I have missed it, it has always been for one-steppers or just where there are 2 or 3 lines of code. In other words, how can you fairly compare these two notations where just a few lines of code are required?

First you call me talented and gifted solver, and then you do not believe yourself ?
I have solved such puzzles before i even knew, what an AIC is. But i stopped it as a waste of time. Why should i spend 4 hours to solve it and 2 to write down a solution, which no one is interested in ? Bad for you.
My way of solving never changed with knowing AIC's. These "or", "then not", "then" (or should i say "equal", "minus", "equal" ? ) were natural for me - and self-detected, if you believe it or not.
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