Sandy's Site

An old friend of mine, Sandy Walsh, has started a blog. Here's his feed too.

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Seven Segment Display in Inkscape

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Today I got a little sidetracked while working on my key-train (keyboard training) project.  I thought I might spruce it up a little by using a seven segment display for the digits (say for the words per minutes), similar to what kTouch has.  I found an open source font, but it appears to be difficult to just use a ttf font in GTK. So I figured, it's only 10 images, I'll just make them in svg. I vaguely remembered a heathenx inkscape podcast  describing how to make an LCD display and decided to use that at my base. Unfortunately, they didn't provide any source files in the show-notes (as far as I could see) so I had to watch and redo the drawings myself! By naming each of the seven segments I could create the 10 digits simply by deleting a few elements in one template svg file .  I can create the template as beautiful as I like and quickly create the 10 derived images with these programs . Unfortunately, both ImageMagick and GraphicsMagick don't handle
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Shortest Sudoku solver in Python

Mark Byer's site has some more Sudoku solvers here's a short one in Python that's only 178 bytes long: def r(a):i=a.find('0');~i or exit(a);[m in[(i-j)%9*(i/9^j/9)*(i/27^j/27|i%9/3^j%9/3)or a[j]for j in range(81)]or r(a[:i]+m+a[i+1:])for m in'%d'%5**18] from sys import*;r(argv[1]) On the site is also shown a longer Perl version at 185 bytes: use integer;sub R{for$i(grep!$A[$_],@x=0..80){%t=map{$_/27-$i/27|$_%9/3-$i%9/3&&amp;amp;amp;$_ /9-$i/9&&($_-$i)%9?0:$A[$_]=>1}@x;R($A[$i]=$_)for grep!$t{$_},1..9;return$A[$i]=0} die@A}@A=split//,<>;R I think the Python version is slightly easier to understand, although they are both quite cryptic. I'm not sure why I find these programs fascinating. I think it reminds me that any program can be written in such a way that it's cryptic, even in Python. In addition, the code is small enough that you should be able to figure out how it works, and may learn something the process. Related is
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