Re^2: [ Natural Sort ]: Sorting a string with numbers

Did you do something wrong? I got what you expected:

#!/your/perl/here

use strict;
use warnings;

my @list = qw(apple1 apple apple20);

my @sorted = @list[
    map { unpack "N", substr($_,-4) }
    sort
    map {
        my $key = $list[$_];
        $key =~ s[(\d+)][ pack "N", $1 ]ge;
        $key . pack "N", $_
    } 0..$#list
];

print "@sorted\n";
[download]

gives:

apple apple1 apple20
[download]

Post your code and let's check it.

-QM
--
Quantum Mechanics: The dreams stuff is made of

Comment on Re^2: [ Natural Sort ]: Sorting a string with numbers Select or Download Code

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Re^3: [ Natural Sort ]: Sorting a string with numbers by blueflashlight (Pilgrim) on Sep 18, 2005 at 02:01 UTC
The whole program is a bit complex and does a bunch of stuff that isn't relavent to this issue, but I've cut out everything but this section that shows the problem I'm having. `#!/usr/bin/perl -w use strict; my @h = ( qw( psapp1 psapp psapp2 psepapp1 psepapp psepapp2 psimgprod pspappuat pswebapp2 pswebapp ) ); my @h_sorted = @h[ map { unpack "N", substr($_,-4) } sort map { my $key = $h[$_]; $key =~ s[(\d+)][ pack "N", $1 ]ge; $key . pack "N", $_ } 0..$#h ]; foreach (@h_sorted) { print "$_\n"; };` [download] When I run this program, with my Perl (This is perl, v5.8.6 built for darwin-thread-multi-2level), I get: `psapp psapp1 psapp2 psepapp1 psepapp2 psepapp psimgprod pspappuat pswebapp2 pswebapp` [download] The "psapp" items sort properly, but the "psepapp" and "pswebapp" ones show the problem I'm asking about. Thanks! -s-	[reply] [d/l] [select]
Re^4: [ Natural Sort ]: Sorting a string with numbers (fix) by tye (Sage) on Sep 18, 2005 at 03:25 UTC
Yeah, that's the problem I discussed elsewhere. Here's a simple fix: `#!/usr/bin/perl -w use strict; my @h = ( qw( psapp1 psapp psapp2 psepapp1 psepapp psepapp2 psimgprod pspappuat pswebapp2 pswebapp ) ); my @h_sorted = @h[ map { unpack "N", substr($_,-4) } sort map { my $key = $h[$_]; $key =~ s[(\d+)][ pack "N", $1 ]ge; $key . pack "CNN", 0, 0, $_ } 0..$#h ]; foreach (@h_sorted) { print "$_\n"; };` [download] This inserts 5 nul bytes which prevents the problem. 1 nul byte is enough to fix this specific case. 4 fixes all cases except for the possibility of "x0" sorting before "x". 5 fixes all cases (provided you don't have nul bytes in your strings). - tye	[reply] [d/l]
Re^5: [ Natural Sort ]: Sorting a string with numbers (fix) by blueflashlight (Pilgrim) on Sep 18, 2005 at 17:41 UTC
You are a hero. Thank you so much ... I even understand your solution, which, in itself is amazing. :-)	[reply]