The New Sudoku Players' Forum

[denis_berthier]

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One function I forgot to document in the last version of the Manual is p-different-numbers-out-of-n ?p ?n

This allows e.g. to randomly extract puzzles from a collection:
(p-different-numbers-out-of-n ?p ?n) will produce a list of p different number within [1 n]

Then use: (extract-lines-in-list ?file-in ?file-len ?list ?file-out) , with
?file-in the original file of puzzles
?file-len the length of the previous file
?list the result if the previous function
?file-out the list of extracted puzzles

Combined in one function:
(extract-lines-in-list ?file-in ?file-len (p-different-numbers-out-of-n ?p ?file-len) ?file-out)

If you want to keep the order of the original file, use function p-different-ordered-numbers-out-of-n instead of p-different-numbers-out-of-n.
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[denis_berthier]

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Following my result here: http://forum.enjoysudoku.com/ur1-1-again-t37404-152.html, I've made minor changes in SudoRules priorities: they now allowi to raise the priorities of deadly patterns as high as before Singles (i.e. just at the start as the theorem requires in order to be able to apply with certainty), or immediately after Singles. However, the default value remains after S3 (Subsets of size 3), which remains IMO a good compromise between not missing a DP and not having too many guardians in the initial ORk-relations.
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