Beefy Boxes and Bandwidth Generously Provided by pair Networks
Just another Perl shrine
 
PerlMonks  

Re: Fast - Compact That String

by CountZero (Bishop)
on Feb 09, 2012 at 23:42 UTC ( #952887=note: print w/replies, xml ) Need Help??


in reply to Fast - Compact That String

Using Bit::Vector.
use Modern::Perl; use Bit::Vector; use Data::Dump qw/dump/; my %conversion = ( ' ' => 0, 0 => 1, 1 => 2, 2 => 3, 3 => 4, 4 => 5, 5 => 6, 6 => 7, 7 => 8, 8 => 9, 9 => 10, A => 11, B => 12, C => 13, D => 14, E => 15, F => 16, G => 17, H => 18, I => 19, J => 20, K => 21, L => 22, M => 23, N => 24, O => 25, P => 26, Q => 27, R => 28, S => 29, T => 30, U => 31, V => 32, W => 33, X => 34, Y => 35, Z => 36, ); my %inverted; my $vector = Bit::Vector->new(6); for ( keys %conversion ) { $vector->from_Dec( $conversion{$_} ); $conversion{$_} = $vector->to_Bin(); $inverted{ $vector->to_Bin() } = $_; } while (<DATA>) { chomp; my $string = join '', map { $conversion{$_} } split //; my $vector = Bit::Vector->new_Bin( 36, $string ); my $bits = $vector->to_Bin; $bits =~ s/([01]{6})/$inverted{$1}/ge; say $bits; } __DATA__ 123456 ZZZZZZ ABCDEF
I know, Bit::Vector is an XS-module, so it doesn't comply with your specs.

On my old laptop, it reads a file of 1 million strings, converts them to the compacted format and reconverts them to the original format (to make sure it worked) in 100 seconds.

CountZero

A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://952887]
help
Chatterbox?
and all is quiet...

How do I use this? | Other CB clients
Other Users?
Others making s'mores by the fire in the courtyard of the Monastery: (7)
As of 2018-06-20 07:55 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?
    Should cpanminus be part of the standard Perl release?



    Results (116 votes). Check out past polls.

    Notices?