Sorting a hash 1

[BenRussell]

I want to find out how to sort a hash in numerical order (largest to smallest) still keeping its name and value intact.

For instance if the hash was :
%Hash = ("FirstName", "1", "ThirdName", "3", "FourthName", "4", "FifthName", "5"

how would I sort the 1,3,4,5 still keeping their names (FirstName, SecondName, etc.) intact? - Ben Russell
- President of Intracor Technologies (

http://intracor.hypermart.net)

 

[tsdragon]

You can't really sort a hash per-se, but you can sort it as you iterate through it. You can get a sorted list of the keys or values. HOWEVER, you can't get the key of a hash based on it's value, so in this case you might do better to invert the keys and the values of the hash and then iterate through a sorted list of the keys (numbers) so you can access the values (names).

That being said, here is a way of iterating through the keys of a hash in order of their values, which is what you want:

foreach my $key (sort 
   {$Hash{$a} <=> $Hash{$b}} (keys %Hash)) {
   # process the hash here
} # end foreach

This sorts the hash by NUMERIC values. To sort by STRING values change the <=> in the block to cmp. Meddle not in the affairs of dragons,
For you are crunchy, and good with mustard.

 

[BenRussell]

What should i put in &quot;#Process the hash here&quot; - Ben Russell
- President of Intracor Technologies (

http://intracor.hypermart.net)

 

[tsdragon]

That depends on what you want to do with the sorted hash. For example, to just print the key/value pairs in order by value:

   $val = $Hash{$key};
   print "key/value: $key / $val\n";

Meddle not in the affairs of dragons,
For you are crunchy, and good with mustard.