Finding a puzzle based on known given squares

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Re: Finding a puzzle based on known given squares

Postby denis_berthier » Fri May 15, 2020 3:51 am

m_b_metcalf wrote:
denis_berthier wrote:Anyway, I find this puzzle very interesting. It has very few minimals compared to the other hard ones.
You might be interested in a pattern that was used in both games 1 and 39 in 'Patterns Game 1.0' (pages 1 and 99), again devised by jpf.
Code: Select all
 . . . 6 . . . . .
 5 7 4 1 . . . 3 .
 2 . . . . . 1 8 5
 . . . . . . . 4 .
 . . . . 5 . . . .
 . 1 . . . . . . .
 6 3 9 . . . . . 2
 . 8 . . . 9 5 7 6
 . . . . . 4 . . .
It yields only five known valid puzzles:


I see. I tried it, but I got nothing after 30 minutes, so I killed the process.

However, the underlying pattern (...X.....XXXX...X.X.....XXX.......X.....X.....X.......XXX.....X.X...XXXX.....X...) gave me this, after some 20 minutes:
...3.....7548...3.6.....215.......4.....9.....7.......398.....4.6...2578.....6... # 16 FN C23.m/S2.p
(probably a morph of some of the 5 known ones)

What makes the Metcalf-B7B (I've seen no other name, so I got used to name it so) so different to me is, the pattern itself doesn't yield much compared to the other hard ones. Though I guess it doesn't matter in a top-down search for the hardest, as the digits are given.
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Re: Finding a puzzle based on known given squares

Postby m_b_metcalf » Fri May 15, 2020 7:40 am

denis_berthier wrote:However, the underlying pattern (...X.....XXXX...X.X.....XXX.......X.....X.....X.......XXX.....X.X...XXXX.....X...) gave me this, after some 20 minutes:
...3.....7548...3.6.....215.......4.....9.....7.......398.....4.6...2578.....6... # 16 FN C23.m/S2.p
(probably a morph of some of the 5 known ones)

I should have written that there are only five known ratings rather than five known puzzles. This is a different puzzle but has the same 1.2 rating as the first of the others.

Regards,

Mike
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Re: Finding a puzzle based on known given squares

Postby coloin » Wed May 20, 2020 2:32 pm

I guess these sorts of puzzle generators like gsf's program - the speed of production depends on the number of ED puzzles which have that particular pattern.
The 23C pattern used in patterns game 1 and 39 with only 3 clues in the middle band actually has over 23000 ED minimal/ mostly non-minimal puzzles, but apparently only 5 different ratings.
Normally these generators would produce many more puzzles much more rapidly , as a more average pattern with 23C might have 1 billion ED puzzles.

In the finite world of sudoku puzzles .....this may well be the same process in the pattern from m_b_metcalf puzzle [ I think it has inherited that tag] ... as this has only 20C it wil have much less puzzles than the 22C patterns in eleven#3 and eleven#22,
Udate
My generation process has stopped at only 112 ED all minimal puzzles for the 20C pattern of the m_b_metcalf puzzle no wonder they were hard to come by !
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Using gsf's program

Postby denis_berthier » Fri Nov 27, 2020 5:20 am

I've recently used gsf's program to generate puzzles with very specific (and symmetric) patterns of givens.

It's the first time I'm generating puzzles (except the controlled-bias ones) and I think it's an interesting exercise, as it shows that patterns are very unequal. Some patterns yield nothing after hours, others yield too many easy puzzles. But all the symmetric patterns I've used give many more high SER (9.0 to 9.3) puzzles than can be obtained with top-down generators. I know this effect of symmetry has already been reported, but it's a different thing to see it by oneself.

Does anyone know the meaning of what appears after the puzzle in the output, on each line, e.g.:
4.......1.5..9..3...2...7.....4.7....8..3..5....8.2.....7...4...3..1..8.9.......5 # 96464 FNBTHWYK C21.m/S8.f
..9..4..1.7..5..3.4..1..5....3..6..7.2..1..9.6..9..1....6..8..2.4..6..7.3..4..8.. # 999 FNBTHXY C27.m/S4.da


C21.m and C27.m give the number of clues but what are 58.f and 54.da?

I guess the FNBTHWYK refer to the rules necessary to solve the puzzle.

But what are the ratings (?) 96464 and 999

I've been looking for a manual for the program, but I couldn't find one.
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Re: Using gsf's program

Postby 1to9only » Fri Nov 27, 2020 8:31 am

denis_berthier wrote:I've been looking for a manual for the program, but I couldn't find one.

for manual: download sudoku.html from: https://drive.google.com/drive/folders/0BwwKLhARRO-BZmFjU1kzaVVwdzQ
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Re: Using gsf's program

Postby denis_berthier » Fri Nov 27, 2020 9:21 am

1to9only wrote:
denis_berthier wrote:I've been looking for a manual for the program, but I couldn't find one.

for manual: download sudoku.html from: https://drive.google.com/drive/folders/0BwwKLhARRO-BZmFjU1kzaVVwdzQ


Thanks, there are commands that can't be re-invented.
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