PHP array grouping and sorting instance _ php instance

This article mainly introduces the PHP array grouping and sorting example. For more information about the PHP array grouping and sorting method, see The PHP array. the array content is roughly as follows:

The code is as follows:

$ List = array (
Array (2, 3, 5 ),
Array (2, 5, 24 ),
Array (3, 8, 6 ),
Array (3, 2, 10 ),
Array (4,7, 20 ),
Array (4,1, 15 ),
Array (6, 4, 10 ),
Array (7,9, 20 ),
);

For ease of expression, I name three columns of numbers and three columns of ABC respectively.

Requirement: columns A are sorted by default. If column A is the same, columns C are arranged in reverse order with the same elements. Column B is actually not involved in sorting, but it is useful in practical use, so I also wrote it out.

Method 1:

The code is as follows:

$ A = $ c = array ();
Foreach ($ list as $ val ){
$ A [] = $ val [0]; // Column
$ C [] = $ val [2]; // column c
}
// Install column a in ascending order, and then install column B in descending order, similar to SQL, orderby a asc, B desc
Array_multisort ($ a, SORT_ASC, $ c, SORT_DESC, $ list );
Print_r ($ list );

Method 2:

The code is as follows:

For ($ j = 0; $ j For ($ I = count ($ list)-1; $ I> $ j; $ I --){
If ($ list [$ I] [0] = $ list [$ i-1] [0] & $ list [$ I] [2]> $ list [$ i-1] [2])
List ($ list [$ I], $ list [$ i-1]) = array ($ list [$ i-1], $ list [$ I]);
}
}