Question on perl function

You can actually sort the hash without creating an array.  Try this:


%people = ("Richardson, Greg" -> 22, "Zog, Mike" -> 23, "Boston, Doug -> 24, "Rudolph, Josh" -> 25, "Fritz, Stacy" -> 26)



foreach ( sort { lc($b) cmp lc($a)}  keys (%people) ) {

      my @names = split /, /;
      my $age = $people{$_};

}


so $names[0] will have the last name, and $names[1] will contain the first name.

ultimatemike showed you an excelent method for for doing the sort (in reverse order).  However, instead of splitting the name into an array, I'd use 2 scalars and I'd make sure the names were translated to titlecase.  My example uses to print statements to show the difference in style of output.


%people = ("richardson, greg" => 22, "Zog, Mike" => 23, "Boston, doug" => 24, "Rudolph, Josh" => 25, "Fritz, Stacy" => 26);

foreach $person ( sort { lc($a) cmp lc($b)}  keys (%people) ) {

   $person =~ s/(\w+)/\u$1/g;  # translate to titlecase
   ($last, $first) = split /, /, $person;

   print "$person is $people{$person} years old\n";
   print "$first $last is $people{$person} years old\n\n";
}

If you really need to use an array, then instead of those print statements, you'd push the info onto the array.

Like this:

push @last_first, "$person $people{$person}";
push @first_last, "$first $last $people{$person}";

Then you can print the array somewhere else in your script. like this:

print "$_\n" foreach @last_first;
print "$_\n" foreach @first_last;

Why not change your data to another structure? I like using record-style hashes for this, because it adds flexibility in both sorting and displaying.
I would use something like:
$person = {
    firstname => 'Greg',
    lastname => 'Richardson',
    age         => 22
};

First I'll convert your %people hash into an array of person records:
my @people = ();
while(my ($k, $v) = each %people) {           # loop over elements
    my ($lname, $fname) = split /, /, $k, 2;    # split the key into name parts
    push @people, {                                      # add anonymous hash to the array
        firstname => $fname,
        lastname  => $lname,
         age         => $v
    };
}

now you can sort your array on one or more keys of the records.

examples:
# sort by last name
my @ns_people = sort {
     $a->{lastname} cmp $b->{lastname}
    } @people;

# sort by last name, firstname ascending, age descending
my @lfa_people = sort {
     $a->{lastname} cmp $b->{lastname} ||        # first sort on last name
     $a->{firstname} cmp $b->{firstname} ||        # next on first name
     $b->{age}          <=> $a->{age}                   # finally, on age descending
    } @people;

you can put whatever criteria into the sort { } block that you need. (Including doing a case insensitive sort).

Outputting your data becomes much more flexible too, since you have separate fields for every part of the person.
Example:
foreach(@lfa_people) {
    printf "Age: %d, name: %s %s\n", $_->{age}, $_->{firstname}, $_->{lastname};
}

Also it makes it easy to filter your data. Say you would only want the people with age 25:
@tf_people = grep { $_->{age} == 25 } @lfa_people;

HTH,

Kandura

Quick question FishMonger, is there any way I can print out the hash itself so I can show the original has data and then the array version?

You could do

use Data::Dumper;

print Dumper( \%people, \@lfa_people);

Thanks FishMonger. I could not figure out how to print out the hash right. Thanks again. :)