in reply to Sorting within a file

use strict;
use warnings;

my @lines;

{
   local *FILE;

   open(FILE, "< filename.in")
   or die("Couln't open input file: $!\n");

   chomp(@lines = <FILE>);
}

my @sorted_lines = map  { $_->[0]}
                   sort { $a->[1] <=> $b->[1] }
                   map  { /^(\d+)/ && [ $_, 0+$1 ] }
             # OR: map  { no warnings; [ $_, 0+$1 ] }
                   @lines;

{
   local *FILE;

   open(FILE, "> filename.out")
   or die("Couln't open output file: $!\n");

   local $, = "\n";
   print FILE (@sorted_lines);
}

[download]

Update: Fixed a warning.

Replies are listed 'Best First'.
Re^2: Sorting within a file
by Anonymous Monk on Mar 04, 2005 at 20:42 UTC 
    my @lines;

{
   local *FILE;

   open(FILE, "< filename.in")
   or die("Couln't open input file: $!\n");

   chomp(@lines = <FILE>);
}

my @sorted_lines = map { $_->[0]}
                   sort ( $a->[1] <=> $b->[1] }
                   map { [ $_, 0+$_ ] }
                   @lines;

{
   local *FILE;

   open(FILE, "> filename.out")
   or die("Couln't open output file: $!\n");

   local $, = "\n";
   print FILE (@lines);
}

Whats with the curly brackets? Here's what I have tried. It looks like
+ the file is already ordered alphabetically by id when I used "du -ks
+ *" but I need it by size which is the numbers. Here's my code, it do
+esnt seem to change the order.

#Push data into an array
die("Cannot open Log file to read from.")
    unless(open(TAKE, "<unix_list.txt"));    

while ($line = <TAKE>) {
    push(@list_all, $line);
}
close(TAKE);    

@list_all = sort { $a <=> $b } @list_all;

die("Cannot open Log file to write to.")
    unless(open(NEW, ">unix_list.txt"));

print NEW @lines;

close(NEW);

    [download]
    Thanks again...
[reply]
[d/l]
      Whats with the curly brackets?

      It provides a scope for the local *FILE and the local $,. I don't like variables hanging around too long, especially when they have destructors (like FILE) or have side-effects (like $,).

[reply]
[d/l]
[select]
        ikegami, its complaining about argument "1260896 abadeno" isnt numeric in addition at the "map { $_, 0+$_ }" line...
[reply]
Re^2: Sorting within a file
by Anonymous Monk on Mar 04, 2005 at 21:04 UTC
    Its still having problems. Error states "Can't use string ("") as an array ref while 'strict ref' is in use at line "map { /^(\d+)/ && $_, 0+$1 }"
[reply]
      You must have a typo somewhere???
[reply]

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