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Re: 3-byte representation

by cavac (Chaplain)
on Oct 12, 2011 at 16:38 UTC ( #931055=note: print w/ replies, xml ) Need Help??


in reply to 3-byte representation

Edit: Ooops, my code only works for unsigned integers. I'll leave it here anyway, might at least come in handy for someone else at a later time... Ok, Here's a simple example of how i did it as a test:

#!/usr/bin/perl use strict; use warnings; my $val = 70000; print "Saving Value: $val\n"; # ENCODE my @bytes; for(my $i = 0; $i < 3; $i++) { $bytes[$i] = $val % 256; if($val) { $val = int($val / 256); } } my $savebytes = pack("ccc", @bytes); # DECODE my @newbytes = unpack("ccc", $savebytes); my $newval = 0; while(scalar @newbytes) { my $byte = pop @newbytes; $newval = $newval * 256; $newval += $byte; } print "Retrieved Value is: $newval\n";

Here's the output:
Saving Value: 70000 Retrieved Value is: 70000
I'm pretty sure there is a better way, but i'm not an expert on all this math stuff... Edit: If you have a lot of numbers to encode/decode, you might want to consider putting that stuff into a C module or use Inline::C for speed.
Don't use '#ff0000':
use Acme::AutoColor; my $redcolor = RED();
All colors subject to change without notice.


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