Ordering a indexed set of keyed arrays

[s_shrum]

I can find a ton of writeups on how to ordering a indexed array ($aData[1]=...)and a ton of writeups on ordering a keyed array ($aData['first']=...).

I am, however having no luck finding a writeup on ordering a indexed array of keyed arrays:

$data[] = array('volume' => 67, 'edition' => 2);
$data[] = array('volume' => 86, 'edition' => 1);
$data[] = array('volume' => 85, 'edition' => 6);
$data[] = array('volume' => 98, 'edition' => 2);
$data[] = array('volume' => 86, 'edition' => 6);
$data[] = array('volume' => 67, 'edition' => 7);

The above is from PHP.NET. However, in their sample code, the key names are known and they code specifically for them in a predefined order. :bemused:

I'm in a situation where the keynames are not known ahead of time and the user will define the keys to order on. I know this sounds sorta lazy but, I'm looking for a pre-built function that would allow me to pass a array and a string of keys (maybe seperated by commas) to order multi-dimensional (associative) arrays.

This seems like a fairly common practice for this sort (Hey, look! A pun) of array construct but I can't seem to find any direct discussion or code for it.

Any help would be greatly appreciated. :-D

TIA

[leatherback]

I feel a challenge for you to write a function 😉

J

[leatherback]

OK, that was a bit nasty.. 😉 But I know you can take it.

Let's get serious. When you say "The user will define the key to sort on". Do you mean: the user will tell 'sort by volume', or 'sort by edition'?

Please try to be very clear on what the function should be able to do..

[s_shrum]

Hehehe.

The user will define the key'ed column to sort on. Given something like:

$adata[0]['first']=..
$adata[0]['mid']=..
$adata[0]['last']=..
$adata[1]['first']=..
$adata[1]['mid']=..
$adata[1]['last']=..

The user (or script call) will define ordering like "order=last,first,mid" or just "order=last"...bearing in mind that the script will handle arrays with different key names...

I did happen to read the rest of that PHP.net article and there was a single field sort function (working with it now) but nothing to do multiples which is were I think I need the help. Here's the code I have now to do single column sorts:

function array_key_multisort(&$arr, $l , $f='strnatcasecmp') {
       return usort($arr, create_function('$a, $b', "return $f(\$a['$l'], \$b['$l']);"));
}

TIA