 P is for Practical PerlMonks

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 ; }

Create A New User
Domain Nodelet?
Node Status?
node history
Node Type: note [id://605020]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others rifling through the Monastery: (5)
As of 2022-01-26 09:23 GMT
Sections?
Information?
Find Nodes?
Leftovers?
Voting Booth?
In 2022, my preferred method to securely store passwords is:

Results (69 votes). Check out past polls.

Notices?