modify the order a list with the help of a hash table

steph_bow has asked for the wisdom of the Perl Monks concerning the following question:

Dear Serene Monks,

My problem is this:

I would like to rearrange a list of data , to classify the list from the smallest hour to the latest hour

My list looks like :(* represents a data : number, ...)

* * * * * 02:50:00 * * *

* * * * * 01:30:00 * * *

* * * * * 05:40:00 * * *

Here is my code, but it does not seem to work.But I have no error messages.

my %Hash;


    while (<INFILE>) {


    my $Line = $_;
        my @Elements = split(";", $Line);
    my $hour = $Elements[5];
    print STDOUT "L'heure vaut $hour\n";
        if ($Elements[5] =~ /^(\d\d):(\d\d):(\d\d)/   ){
        my $time = 3600*$1+60*$2+$3;
        $Hash{"$time"} = $Line;
        print STDOUT "the value of the Hash couple is $Hash{$time}";
        }
    }
    close INFILE;


print SDOUT "%Hash";
my @KEYS = keys(%Hash);
sort(@KEYS);

print STDOUT "The set of the keys is @KEYS";

my $hour_triee;
    foreach $hour_triee(@KEYS){
    print OUTFILE "$Hash{$hour_triee}";
    }

close OUTFILE;
[download]

Comment on modify the order a list with the help of a hash table Download Code

Replies are listed 'Best First'.
Re: modify the oder a list with the help of a hash table by ikegami (Patriarch) on Jul 26, 2007 at 15:55 UTC
`sort` returns the sorted list. It doesn't modify the argument. `@KEYS = sort(@KEYS);` [download] Furthermore, since you're converting the timestamps to numbers, you want to do a numerical comparison instead of a lexical comparison. `@KEYS = sort { $a <=> $b } @KEYS;` [download] But you could simply use `$Elements[5]` as the keys and a lexical comparison. Update: By the way, here's another way of doing what you want (fast): `my @triee = map { substr($_, 8) } sort map { (split(/;/, $_))[5] . $_ } <INFILE>; foreach my $triee (@triee) { print OUTFILE $triee; }` [download]	[reply] [d/l] [select]
Re: modify the oder a list with the help of a hash table by FunkyMonk (Bishop) on Jul 26, 2007 at 16:55 UTC
I'd like to add to other monks' comments by adding that `use strict; use warnings;` [download] would have caught your mistake with sort.	[reply] [d/l] [select]
Re: modify the oder a list with the help of a hash table by snopal (Pilgrim) on Jul 26, 2007 at 16:00 UTC
I try to remove all odor from my code, not just mask it. Wait! You must mean sorting order... `@KEYS = sort @KEYS;` [download] Assignment of the result is missing from your code. Also, unless you have a logic issue (time not reported in 24 hour format) you should be able to string sort that time field directly. `$Hash{$Element[5]} = $Line;` [download]	[reply] [d/l] [select]
Re: modify the order a list with the help of a hash table by shmf (Novice) on Jul 27, 2007 at 14:32 UTC
Hi, try this! ;) I think it is more flexible that your code because it needs not your file lines' to have exactly one specific format. `use warnings; use strict; use Cwd; my $path=cwd(); my %Hash; my $line; my $seconds=0; my $pathC = $path . '/data.txt'; open INFILE, "$pathC" or die "Cant open file $pathC\n"; while ($line = <INFILE>) { if($line =~ m/.(\d{2}):(\d{2}):(\d{2})./){ $seconds = 3600$1+60$2+$3; $Hash{$seconds}=$line; } } close INFILE; for my $key (sort { $a <=> $b } (keys %Hash)){ print "$Hash{$key}"; }` [download]	[reply] [d/l]