sorting of hash of hash in perl

[nirmal1349]

Hi,
Lets say I have the following hash structure in perl:

my %products (
    1 => {
        name      => "Floor Wax",
        wholesale => "50.00",
        retail    => "abc1.doc",
        category => "abc",
    },
    2 => {
        name      => "Paper Towel",
        wholesale => "20.00",
        retail    => "abc2.doc",
        category => "abc",
    },
    3 => {
        name      => "Hand Soap",
        wholesale => "30.00",
        retail    => "xyz1.doc",
        category => "xyz",
   },
);
 I want the o/p as :
 
   abc 
      abc1.doc
      abc2.doc
   xyz
      xyz1.doc

pls tel me how will I perform sorting on this hash.
Reply asap...

[Ganon11]

A hash has no order. You cannot sort the hash directly. What you can do is sort the keys of the hash (by getting the keys in a list using the keys function), and then access the hash with those keys in sorted order.

You will need to write a short subroutine to say how you are sorting: i.e. you and not comparing the keys, but the field of the hash referred to by the key.

[KevinADC]

Have you tried to sort the data?

reply ASAP....

[nirmal1349]

hi,
I tried sortin the data using smethng like this:

for my $key1 (reverse sort { $mydata{$b}{'Category'} cmp $mydata{$a}{'Category'} } keys %mydata) {....

}

here i can get the hash sorted using Category but then I need to go deep and further sort it by the retail value...
i tried using diffrnt loops but cld not arive at the answer..
Reply asap

[KevinADC]

one possible way:

my %products = (
1 => {
name => "Floor Wax",
wholesale => "50.00",
retail => "abc1.doc",
category => "abc",
},
2 => {
name => "Paper Towel",
wholesale => "20.00",
retail => "abc2.doc",
category => "abc",
},
3 => {
name => "Hand Soap",
wholesale => "30.00",
retail => "xyz1.doc",
category => "xyz",
},
4 => {
name => "Hand Soap",
wholesale => "30.00",
retail => "xyz2.doc",
category => "xyz",
},
);

my @sorted = map{"$_->[2] $_->[3] $_->[0] $_->[1]"}
             sort{$a->[3] cmp $b->[3] || $a->[2] cmp $b->[2]} 
             map{ [$products{$_}{'name'},$products{$_}{'wholsale'},$products{$_}{'retail'},$products{$_}{'category'}] } keys %products;

print "$_\n" for @sorted;