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### Re: Storing variable coordinates in a matrix

by davidrw (Prior)
 on Mar 15, 2007 at 16:46 UTC ( #605020=note: print w/replies, xml ) Need Help??

in reply to Storing variable coordinates in a matrix

the my @A assignment uses the values of \$x and \$y at that time, and then you get an AoA of static numbers .. changing \$x and \$y after the fact will have no effect. I believe what you're looking for is a function, so you can pass in \$x and \$y and get back the array calculated for those two values.
```sub makeBoxArray {
my (\$x, \$y) =  @_;
return (
[ ([\$x, \$y  ]), ([\$x+1, \$y  ]), ([\$x+2, \$y  ]), ([\$x+3, \$y  ]) ],
[ ([\$x, \$y+1]), ([\$x+1, \$y+1]), ([\$x+2, \$y+1]), ([\$x+3, \$y+1]) ],
[ ([\$x, \$y+2]), ([\$x+1, \$y+2]), ([\$x+2, \$y+2]), ([\$x+3, \$y+2]) ],
[ ([\$x, \$y+3]), ([\$x+1, \$y+3]), ([\$x+2, \$y+3]), ([\$x+3, \$y+3]) ],
);
}

my @A = makeBoxArray( 5, 10 );
# use @A for something
@A = makeBoxArray( 7, 2 );
# use @A for something
To take it a step further, the array can be generated using map to eliminate the repetitive text, and also add optional params for the box size:
```sub makeBoxArray {
my \$left = shift;
my \$top = shift;
my \$width = shift || 4;
my \$height = shift || 4;
return map {
my \$y = \$_;
[ map { [\$left+\$_, \$top+\$y] } 0 .. \$width-1 ]
} 0 .. \$height-1 ;
}

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 [Corion]: ... an aggregator site that also listed (ideally) all of these links once. And maybe also have an exclude list to blacklist some of the most spammy links that the site may have never mentioned at all [marto]: I gave up reading HN at all, and feel much better for it :P [Corion]: Now, how to best automate that Google search ... :-) [Corion]: marto: Yeah, I'm also short of not reading it at all. I already stopped reading it in the morning because it gave me a foul mood. [Corion]: The good posts on HN are the non-computing posts. Most of the other stuff is maybe relevant to you if you are 20 and live in Silicon Valley... [Corion]: Two attributes that don't describe me. [Corion]: Maybe I should also write a curator for HN or simply not read it anymore, like you do.

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