calculating frequency of item in an array

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

Hi monks, I am trying to write a hash to calculate the frequency of itmes in an array. I have managed to get the code to print the array in order of frequency, but also want to calculate and print how often each item occurs - this is where i'm struggling. Can anyone help??

# heres a snippet

# @items contains all the thing i want to calculate frequency of.

 print "Items: @items\n";

 # determine the frequency of each item. Sort them in ascending order.

               my %freq;
               my $count;
 
               foreach  $pair (@items)   {

                   $freq{$pair}++;

               }

# next foreach not working - want to print no of each individual item

               foreach $pair (@items)   {

                  ++$count;

               }


               my @array = sort { $freq{$b} <=> $freq{$a} } keys %freq
+;
               print "Sorted:@array\n";
               print "Count:$count\n";
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Re: calculating frequency of item in an array by davorg (Chancellor) on Feb 27, 2003 at 10:31 UTC
I think you want something like this: `my %freq; $freq{$_}++ for @items; foreach (sort { $freq{$b} <=> $freq{$a} } keys %freq) { print "$_ : $freq{$_}\n"; }` [download] -- <http://www.dave.org.uk> "The first rule of Perl club is you do not talk about Perl club." -- Chip Salzenberg	[reply] [d/l]