random sudokus

[This article was first published on Xi'an's Og » R, and kindly contributed to R-bloggers]. (You can report issue about the content on this page here)
Want to share your content on R-bloggers? click here if you have a blog, or here if you don't.

In a paper arXived on Friday, Roberto Fontana relates the generation of Sudoku grids to the one of Latin squares (which is unsurprising) and to maximum cliques of a graph (more surprising). The generation of a random Latin square proceeds in three steps:

  1. generate a random Latin square L with identity permutation matrix on symbol 1 (in practice, this implies building the corresponding graph and picking one of the largest cliques at random);
  2. modify L into L’ using a random permutation of the symbols 2,…,n in L’;
  3. modify L’ into L” by a random permutation of the columns of L’.

A similar result holds for Sudokus (with the additional constraint on the regions). However, while the result is interesting in its own right, it only covers full Sudokus, rather than partially filled Sudokus with a unique solution, whose random production could be more relevant. (Or maybe not, given that the difficulty matters.) [The code uses some R packages, but then moves to SAS, rather surprisingly.]


Filed under: Books, R, Statistics Tagged: arXiv, cliques, graphs, sudoku

To leave a comment for the author, please follow the link and comment on their blog: Xi'an's Og » R.

R-bloggers.com offers daily e-mail updates about R news and tutorials about learning R and many other topics. Click here if you're looking to post or find an R/data-science job.
Want to share your content on R-bloggers? click here if you have a blog, or here if you don't.

Never miss an update!
Subscribe to R-bloggers to receive
e-mails with the latest R posts.
(You will not see this message again.)

Click here to close (This popup will not appear again)