On Mon, 2008-12-15 at 20:33 -0500, Christopher Yee Mon wrote:
> I have an array of strings whose members consist of a number followed by
> a comma followed by a text string
>
> e.g.
> 1,fresh
> 2,testurl
>
> I want to sort by descending numerical order according to the number
> part so I made this sort subroutine
>
> sub by_counter_field {
> my($a, $b) = @_;
> $a =~ s/^(.*?),.*/$1/g;
> $b =~ s/^(.*?),.*/$1/g;
>
> if ($a > $b) { -1 } elsif ($a < $b) { 1 } else { 0 }
> }
>
> and sorted it with
> sort by_counter_field @array;
> and it didn't work.
>
> I've also tried replacing
> if ($a > $b) { -1 } elsif ($a < $b) { 1 } else { 0 }
> with
> $b <=> $a
> and it still didn't work.
>
> I also tried this
> sort { ($b =~ /(.*?),.*/)[0] <=> ($a =~ /(.*?),.*/)[0] } @array;
> and it didn't work either.
>
> I can't figure it out for the life of me
>
> Any assistance would be deeply appreciated.
Use the Schwartzian transform:
#!/usr/bin/perl
use strict;
use warnings;
my @array = ();
while( <DATA> ){
chomp;
push @array, $_;
}
my @sorted = map { $_->[0] }
sort { $b->[1] <=> $a->[1] # descending numeric
|| $a->[2] cmp $b->[2] } # ascending alphabetic
map { [ $_, split( /,/, $_ ) ] }
@array;
for ( @sorted ){
print "$_\n";
}
__DATA__
1,fresh
2,testurl
2,another
--
Just my 0.00000002 million dollars worth,
Shawn
The key to success is being too stupid to realize you can fail.
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