|New Datafile articles|
Message #1 Posted by Valentin Albillo on 20 June 2005, 5:24 a.m.
Just a quick post (too busy am I ...) to let you know
that two new articles from mine do appear published in
the latest May-June issue of Datafile (V24 N3), namely:
- HP-71B Fantastic FOUR
This completes my survey of the awesome HP-71B Math ROM's capabilities featured in my previous HP-71B Math ROM Baker's Dozen (Vols. 1 & 2) articles (Datafile V24N1 & V24N2), with a 14th item, this time entirely dedicated to an amazing and, to most people, unexpected application of the rarely used FOUR keyword. The 8-page article includes an extremely short (8-10 line) subprogram to prove the point, which implements the desired functionality by using FOUR at THREE different places ! :-)
... And in case you might be wondering what it does do in 8 lines, well, just things like this:
only real fast and with much bigger numbers ...
- HP-71B Sudoku Solver's Sublime Sequel
A sequel to my original 35-line HP-71B Short & Sweet Sudoku Solver published in Datafile V24N2, which improves its speed enormously at the expense of just 10 additional lines of code, for a total of 45 lines (half a regular 80-line printed page), well under 2 Kb. Together they form a combined 19-page article which discusses important techniques for this kind of solvers (e.g., bitboards and boolean operations), plus it includes a thorough, 15-item Test Suite, to allow the reader to test any Sudoku solvers out there, or even his/her own human capabilities.
(Matter of fact, I did have this 'sequel' ready and working perfectly before my originally submitted article was published, and I contacted Datafile's Editor, Bruce Horrocks for him to drop it and publish this improved version instead, which would thus have appeared in V24N2. Bruce agreed, but personal complications arised and I was unable to find enough free time to rewrite the already existing article from scratch, so I further told him to go on with publishing the first version anyway, till I could find the time to submit the improved version properly formatted for its publication in Datafile. This is it!)
I hope you'll enjoy them. Also, in this same issue, "Slow Sudoku on the HP-12C" by Tony Hutchings boldly goes where no one dared before, implementing a Sudoku solver/assistant in both a regular HP-12C as well as a 200-step version for the HP-12C Platinum. For such a fan of the HP-12C as myself, this is really a must reading as well.
Best regards from V.
Edited: 20 June 2005, 5:51 a.m.