Beefy Boxes and Bandwidth Generously Provided by pair Networks
Your skill will accomplish
what the force of many cannot
 
PerlMonks  

Comment on

( #3333=superdoc: print w/ replies, xml ) Need Help??

Thanks. I keep forgetting how broken un/pack are in this respect. Having "B6" load the high six bits (of the low byte of the integer) is just non-sensical.

So for the most sane configuration (bits split based on base-2 representation not some "ascending bit order" representation) you have to work harder:

my @fields= unpack "C*", # 16 6-bit numeric values pack "b6"x16, # string of 16 bytes, each holding a 6-bit value map ''.reverse, # 16 6-character ascending-bit strings unpack "a6"x16, # 16 6-character base-2 strings unpack "B*", # 96-character base-2 string "twelve bytes"; # 12-byte packed string print "(@fields)\n"; my $string= pack "B*", # 12-byte packed string pack "a6"x16, # 96-character base-2 string map ''.reverse, # 16 6-character base-2 strings unpack "b6"x16, # 16 6-character ascending-bit strings pack "C*", # string of 16 bytes, each holding a 6-bit value @fields; # 16 6-bit numeric values print "($string)\n";

outputs:

(29 7 29 37 27 7 25 37 8 6 9 57 29 6 21 51) (twelve bytes)

- tye        


In reply to Re^4: pack/unpack 6-bit fields. (insanity) by tye
in thread pack/unpack 6 bit fields. by Anonymous Monk

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":



  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.
  • Log In?
    Username:
    Password:

    What's my password?
    Create A New User
    Chatterbox?
    and the web crawler heard nothing...

    How do I use this? | Other CB clients
    Other Users?
    Others musing on the Monastery: (6)
    As of 2015-07-04 21:50 GMT
    Sections?
    Information?
    Find Nodes?
    Leftovers?
      Voting Booth?

      The top three priorities of my open tasks are (in descending order of likelihood to be worked on) ...









      Results (60 votes), past polls