Is it the keys or the values that are sorted? I will assume keys, but you can apply anything you like later:

update – ww pointed out that @k/$pct only works when $pct == 10. I feel sheepish, but I've corrected the code below. :-/ 

my @k = sort keys %the_hash;

my $pct = 10; # what percent to print
#- WRONG -# for ( 0..int(@k/$pct)-1 ) {
for ( 0.. int( @k * ($pct/100) ) )-1 ) {
   printf "%s => %s\n", $k[$_], $the_hash{$k[$_]}
}

[download]

Or, if you want to keep the top x% and discard the rest: 

my @k = sort keys %the_hash;

my $pct = 10; # what percent to keep
#- WRONG -# for ( int(@k/$pct)-1..$#k ) { delete $the_hash{$k[$_]} }
for ( int( @k * ($pct/100).. ) )-1..$#k ) {
   delete $the_hash{$k[$_]} 
}
# Now %the_hash only contains the top 10%

[download]
<-radiant.matrix->
A collection of thoughts and links from the minds of geeks
The Code that can be seen is not the true Code
I haven't found a problem yet that can't be solved by a well-placed trebuchet

In reply to Re: Selection of Hash key value pairs by radiantmatrix
in thread Selection of Hash key value pairs by Gavin

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