Read files, lines into array, cat vs open

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# 1  
Old 11-12-2009
Read files, lines into array, cat vs open

Hi Everyone,

I have a file: a.txt

use warnings;
use strict;
my @array = ();
### Load file into array
for my $i (split '\n', `cat /tmp/a.txt`) {
    push @array, [ split ',', $i ];

It works. But my a.txt have 1million lines, and each lines have 17 fields. If use 'cat' like above, it takes veeeeeeeeeery long time.

How to do it using open?, especially need to split ',' for each line.Smilie

# 2  
Old 11-12-2009
open my $FH, '<', '/tmp/a.txt' or die "Can't open a.txt: $!";
while ( my $line = <$FH> ) {
    chomp $line; # remove the newline at the end
    push @array, [ split ',', $line ];
close $FH;

Or (perlisher)
open my $FH, '<', 'a.txt';
@array = map { chomp; [ split ',' ] } <$FH>;
close $FH;

# 3  
Old 11-12-2009
[/COLOR]Smilie much much more faster now! Thanks Smilie

Last edited by jimmy_y; 11-12-2009 at 06:44 AM..
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