Re^2: Hash value interpolation

Thanks ikegami, your idea gets me closer however, I get no output. Looks like I'm still doing something incorrect. Below is my actual test script:

use warnings;
use strict;

my $COLOR=2;
my $hm="";
my $ht="";

my %h1 = (
                   "1" => "blue"
);

my %h2 = (
                   "2" => "green"
);

if ( $COLOR == 1 ) {
     $ht=\%h1;
}
elsif ( $COLOR == 2 ) {
     $ht=\%h2;
}

sub geth {

      while ((my $key, my $value) = each(%$ht)) {
          if ( $key == $COLOR ) {
              $hm=$value;
          }
      }
         print "$hm\n";
}
[download]

Comment on Re^2: Hash value interpolation Download Code

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Re^3: Hash value interpolation by ikegami (Patriarch) on Feb 16, 2009 at 21:59 UTC
I don't know why you have two hashes in the first place. `my %colors = ( "1" => "blue", "2" => "green", ); my $COLOR = 2; # 1..2 sub geth { print "$colors{$COLOR}\n"; } geth();` [download] Or why you aren't using an array. `my @colors = ( "blue", "green", ); my $COLOR = 1; # 0..1 sub geth { print "$colors[$COLOR]\n"; } geth();` [download]	[reply] [d/l] [select]
Re^4: Hash value interpolation by csarid (Sexton) on Feb 17, 2009 at 22:44 UTC
Thanks for all the help everyone... responding to ikegami's two points, the reason for the two hashes is because I wanted to simplify the code sample to focus on my problem, but the idea was to select a hash table to use based on a calculation. Also, the hash table makes the data elements much more readable for me. Is there a performance gained by using an array over the hash? Thanks gain!	[reply]
Re^5: Hash value interpolation by ikegami (Patriarch) on Feb 17, 2009 at 23:01 UTC
the reason for the two hashes is because I wanted to simplify the code You didn't do that. Your data structure is horribly complex. What's the point of having a hash for every key! (And don't say "1" and "2" could be the same string because then your goal makes no sense at all. There wouldn't be a right "hm" to fetch.) Is there a performance gained by using an array over the hash? Performance? Not really. The problem is that emulating a hash using an array is one more thing that can go wrong compared to just using an array.	[reply]
Re^6: Hash value interpolation by csarid (Sexton) on Feb 18, 2009 at 05:14 UTC
Re^3: Hash value interpolation by kyle (Abbot) on Feb 16, 2009 at 21:16 UTC
It appears that `geth()` is never called. If I fix that, the output is "green".	[reply] [d/l]


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