Hokay, Perl questions start here :)

[Gayle29uk]

I got a book, now the silly questions

From what I understand it's possible to sort a multi dimensional array based on whatever 'hash'(?) you want.

e.g. if I have $planets['id']['score'] and $planets['id']['roids'] I can choose which to sort on and everything else stays linked to it's key (i.e. all the planet info stays linked to the correct $planets['id'] but the order is changed.

Have I got that right? If I have then I have to rewrite my PA dump script in Perl immediately

[edit] Excuse the PHP syntax, haven't got past reading the Perl stuff yet [/edit]

[W]

No. There are ways to do it that doesn't take too long tho, but you need some looping.

[queball]

Originally posted by W
No. There are ways to do it that doesn't take too long tho, but you need some looping.

Huh? @id_sorted = sort {$a->{"id"} <=> $b->{"id"}} @planets;

Unless I've misunderstood.

[Gayle29uk]

Originally posted by queball
Huh? @id_sorted = sort {$a->{"id"} <=> $b->{"id"}} @planets;

Unless I've misunderstood.

That makes sense but can I do it with say...

@id_sorted = sort {$a->{"id"} {"score"}<=> $b->{"id"}{"score"}} @planets;

???

[queball]

OK, I don't understand why you'd have a structure like that. How far are you in your perl book?

[KaneED]

Spinner is apparently a Perl 'god', ask him for help

[Gayle29uk]

Originally posted by queball
OK, I don't understand why you'd have a structure like that. How far are you in your perl book?

Imagine the structure...

@planets['id']['score']
@planets['id']['rank']
@planets['id']['roids']
@planets['id']['roidrank']

Make sense now? Lots of subfields for each planet

[queball]

Originally posted by Gayle29uk
Imagine the structure...

@planets['id']['score']
@planets['id']['rank']
@planets['id']['roids']
@planets['id']['roidrank']

Make sense now? Lots of subfields for each planet

Nope. Do I replace 'id' with a number?
Like,
$planets[5]{score}=56515;
$planets[5]{roids}=56;
?

Then,
$rank=1; $_{rank}=$rank++ foreach sort {$a{score} <=> $b{score}} @planets;
or somesuch. I don't get this ['id'] business.

[Atamur]

I think you need to be a bit more specific about the data structure you are trying to work with. Perl has 3 data structures. scalar, list, and hash. From your description you seem to want a hash of hashes. If so, you cannot sort that because a hash is an unordered structure. However, you can come up with a list of keys that will correspond to an ordered sequence of hash mappings. i.e.

%planets = (
'id1' => {'id'=>'id1', 'roids' => 3, 'score' => 10000},
'id2' => {'id'=>'id2', 'roids' => 6, 'score' => 15000}
);

@roidIDs = map {$_->{'id'}} sort {$a->{'roids'} <=> $b->{'roids'}} values %planets;

This is a strange way of organizing this data though. What queball suggested (a list of hashes) is much more straightforward.

[Gayle29uk]

Originally posted by queball
Nope. Do I replace 'id' with a number?
Like,
$planets[5]{score}=56515;
$planets[5]{roids}=56;
?

Then,
$rank=1; $_{rank}=$rank++ foreach sort {$a{score} <=> $b{score}} @planets;
or somesuch. I don't get this ['id'] business.

Yes, id is a number think of it as a primary key sort of thing

Otherwise I'd end up with a list of scores nicely sorted in order but no idea whatsoever which planet they belonged to

[DarknessX]

I think good reads around perldoc perlref and perldoc perlreftut are in order. You want to create hashrefs (or arrayrefs) to scalars in your code. After you've taken a gander at the perldocs, try reading this: http://www.perlmonks.org/index.pl?node_id=90647 (How to handle multidimensional arrays)